Preservatives for molecular sample analysis with sample collection devices

Abstract

Provided are compositions of preservatives for use in custom sample collection devices. Methods of collecting biological analytes using the sample collection devices are also provided. The compositions and methods provided allow for improvements in the recovery, stability, and signal enhancement of biological analytes.

Description

PRESERVATIVES FOR MOLECULAR SAMPLE ANALYSIS WITH SAMPLECOLLECTION DEVICESCROSS-REFERENCE TO RELATED APPLICATIONS[1] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 586,943, filed on September 29, 2023, the contents of which are incorporated herein by reference in their entirety.BACKGROUND[2] The human metabolome includes at least 200,000 small molecules, of which only a few thousand can be profiled in biological samples. The rest constitute a “dark metabolome,” either because technologies are not able to detect them except by inference or because they can be detected but have not yet been identified chemically. DNA, RNA, and proteins are the main focus in studying cancer biomarkers, but metabolites can shed light on many of the re-wired pathways that determine the life, death, and evolution of cancer cells. Metabolite levels reflect the combined effects of genetics, environment, and lifestyle (e.g., diet and exercise). There have been many cases to date (e.g., ATP, cholesterol, epinephrine, glucose, triglycerides, vitamins) in which increasing the inventory of known and measured metabolites has resulted in biomedical advances.SUMMARY[3] According to one aspect of the present disclosure, compositions of preservatives and methods of collecting samples of biological analytes using sample collection devices with individual preservatives and / or a combination of preservatives are provided.[4] In an aspect, provided is a system comprising: a) a sample collection device; and b) a preservative system comprising a preservative, wherein the preservative is selected from the group consisting of an antioxidant, a chelator, an inert gas, an inert host structure, a kosmotrope, a protein precipitator, and a combination of two or more thereof.[5] In another aspect, provided is a method of collecting a biological analyte, the method comprising: delivering a preservative system into a sample collection device; delivering a biological sample to the sample collection device; processing the biologicalsample to obtain a solution containing the biological analyte; and collecting the biological analyte; wherein the preservative system stabilizes the biological analyte for analysis.[6] In another aspect, provided is a preservative system for improving the signal of a biological analyte through increased recovery, stabilization and / or other signal-enhancing mechanism, the preservative system comprising: a preservative selected from the group consisting of an antioxidant, a chelator, an inert gas, an inert host structure, a kosmotrope, and a protein precipitator, and a combination of two or more thereof.[7] Both the foregoing summary and the following detailed description are exemplary and explanatory. They are intended to provide further details of the disclosure but are not to be construed as limiting. Other objects, advantages, and novel features will be readily apparent to those skilled in the art from the following detailed description of the disclosure.BRIEF DESCRIPTION OF THE DRAWINGS[8] FIGs. 1A-1D. Effects of selected preservatives on the stabilization and / or recovery of selected analytes. Metabolites were extracted from the MCF7 breast cancer cell line without or with indicated preservatives and immediately processed using mass spectrometry workflows. FIG. 1A) Putrescine is an example of an unstable analyte that is not stabilized by the preservatives tested. FIG. IB) Deoxy cytidine triphosphate (dCTP) is an example of an unstable analyte that is not stabilized by most of the preservatives tested, but its signal is increased by the addition of vitamin C + deferoxamine and quercetin + deferoxamine. FIG. 1C) Fumarate is an example of an unstable analyte that is stabilized by the addition of BHT + phloroglucinol but none of the other preservatives included in this test. FIG. ID) Galactaric acid is an example of a poorly recovered and / or poorly ionized analyte (possibly a “dark metabolite” that is undetected under routine analytical conditions) for which the signal is increased significantly by the addition of a number of preservative combinations.[9] FIG. 2. Custom blood collection tubes reveal potential under-treatment of patients with L-asparaginase. Whole blood from patients treated with two different variants of L-asparaginase (Oncaspar or Erwinaze) was collected into tubes containing a preservative that stabilizes asparagine (Asn). The results indicate failure to deplete Asn below the threshold of 30 pM in half of the patients (most clearly illustrated in Patients 4 and 6). Although L-asparaginase has been FDA-approved since 1978, the instability of Asnin the presence of L-asparaginase prevented the scientific community from discovering this phenomenon and its prevalence. These results prompt the need for new clinical trials to optimize the treatment regimen and have the potential to change clinical practice and improve patients’ lives.

[0010] FIGs. 3A-3G. Levels of cell-based metabolites (amino acids) in the presence of preservatives (e.g., quercetin (Q), butylated hydroxytoluene (B), phloroglucinol (P), A- cyclodextrin (A), Vitamin C (V), deferoxamine (D), and 5-sulfosalicyclic acid (S)) over a 5- month time period.

[0011] FIGs. 4A-4B. Levels of cell-based metabolites (fatty acids) in the presence of preservatives (the same preservatives used in FIG. 3) over a 5-month time period.

[0012] FIGs. 5A-5E. Levels of cell-based metabolites (from the glycolysis pathway) in the presence of preservatives (the same preservatives used in FIG. 3) over a 5-month time period.

[0013] FIGs. 6A-6M. Levels of cell-based metabolites (nucleotides) in the presence of preservatives (the same preservatives used in FIG. 3) over a 5-month time period.

[0014] FIGs. 7A-7E. Levels of cell-based metabolites (organic acids and related metabolites) in the presence of preservatives (the same preservatives used in FIG. 3) over a 5-month time period.

[0015] FIGs. 8A-8D. Levels of cell-based metabolites (from the pentose phosphate pathway) in the presence of preservatives (the same preservatives used in FIG. 3) over a 5- month time period.

[0016] FIGs. 9A-9C. Levels of cell-based metabolites (from the tricarboxylic acid (TCA) cycle) in the presence of preservatives (the same preservatives used in FIG. 3) over a 5- month time period.

[0017] FIG. 10. Levels of riboflavin-cyclic-4-5-phosphate in the presence of preservatives (the same preservatives used in FIG. 3) over a 5-month time period.DETAILED DESCRIPTION

[0018] Various embodiments are described hereinafter. It should be noted that the specific embodiments are not intended as an exhaustive description or as a limitation to the broader aspects discussed herein. One aspect described in conjunction with a particular embodiment is not necessarily limited to that embodiment and can be practiced with any other embodiment(s).I. Overview

[0019] There is a large percentage of metabolites (e.g., sugars, amino acids, lipids, and other small molecules) that are not able to be measured accurately or measured at all when biological samples are analyzed. The human metabolome is estimated to include at least 200,000 metabolites, of which roughly 2,000 (1%) can be measured by standard methods in a typical biological sample. The rest constitute a “dark metabolome,” either because current technologies are not able to detect them except by inference or because they can be detected but have not yet been identified chemically.

[0020] Metabolites are essential for cancer research because they reflect the combined effects of genetics, environment, and lifestyle (e.g., diet); they are at the business ends of many processes that fundamentally determine the life, death, function, and evolution of cancer cells. Cancers tend to re-wire their metabolic circuitry to give themselves a growth advantage as they evolve in the body. Current technologies and sample preparation protocols do not permit detection or characterization of most metabolites in biological samples. Additionally, many metabolites are unstable and change before they can be identified or chemically characterized.

[0021] More generally, there is an unmet need to develop new sample collection methods and compositions that preserve unstable metabolites for research. Hundreds of millions of blood samples are drawn from patients each year globally, but current biobanking techniques fail to stabilize the metabolome.

[0022] Compositions, apparatuses, systems, and methods in accordance with the present disclosure can provide for compositions of preservatives and methods of collecting biological analytes using custom sample collection devices that include individual preservatives or combinations thereof. The compositions and methods described herein provide improved recovery and / or stabilization of a wide range of analytes including but notlimited to metabolites, lipids, and proteins, resulting in more accurate quantitation than can be obtained compared to existing sample collection technologies. For example, various such compositions and methods can enable complete or partial stabilization of analytes to a greater extent and / or duration than achieved previously.

[0023] The compositions and methods described herein can account for improved signal of analytes through one or more mechanisms including increased stability, increased recovery, increased ionization efficiency, and / or other mechanisms, as well as analytical techniques or devices for which the analytes are being preserved (for example and without limitation, mass spectrometry (MS), which can include ion chromatography-mass spectrometry (IC- MS), hydrophilic interaction chromatography (HILIC)-MS, liquid chromatography-mass spectrometry (LC-MS), gas chromatography-mass spectrometry (GC-MS), or capillary electrophoresis-MS (CE-MS)); for example, in some instances a preservative or preservative system can be selected or configured according to at least one of a stability criterion, a recovery criterion, an ionization efficiency criterion, or a target analytical technique / device for which the analyte is to be preserved.

[0024] As used herein, “stability” refers to the ability of a molecule and / or biological analyte to resist change, decomposition, or degradation. As used herein, “recovery” refers to the ability to collect or retrieve a molecule and / or biological analyte after processing a biological sample. As used herein, “ionization efficiency” refers to the ability of a molecule or biological analyte to undergo ionization by any of a variety of techniques in the early stage of MS analysis (e.g., electrospray ionization, electron impact, chemical ionization, atmospheric pressure chemical ionization, atmospheric pressure photoionization, matrix assisted laser desorption and ionization).II. Compositions

[0025] Provided herein are compositions of preservatives, or preservative systems, for use in collecting biological analytes. The compositions described show superior properties including improved recovery, improved ionization efficiency, enhancement or improvement of signals, and / or improved stabilization of a wide range of biological analytes compared to existing sample collection technologies. Improved recovery, ionization efficiency, signal, and / or stability of the biological analyte refers to an increase in recovery, ionization efficiency, signal, and / or stability of the biological analyte in the presence of a preservativecompared to the recovery, ionization efficiency, signal, and / or stability of the biological analyte in the absence of a preservative.

[0026] Suitable classes of preservatives for use in the compositions include, but are not limited to, antioxidants, chelators, inert gases, inert host structures, kosmotropes, protein precipitators, or a combination of two or more thereof.

[0027] Suitable preservatives for use in the compositions include, but are not limited to 3,4- dihydroxyphenylacetic acid, 5-sulfosalicylic acid (SSA), alpha-cyclodextrin, alphatocopherol (vitamin E), alpha-tocotrienol (vitamin E), andrographolide, apigenin, betacyclodextrin, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin hydrate, chlorogenic acid, cyanidin, deferoxamine, diethylenetriaminepentaacetic acid (DTP A), epigallocatechin gallate (EGCG), ethoxyquin, ethylenediaminetetraceticacid (EDTA), ferulic acid, gammacyclodextrin, glycerol, gingerol, isomalt, liproxstatin-1 (Lip-1), mannitol, N-acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, sorbitol, trichloroacetic acid (TCA), trifluoroethanol (TFE), tris(2-carboxyethyl)phosphine (TCEP), vitamin Bl (thiamine), vitamin C (ascorbic acid), vitamin C (ascorbyl palmitate), and a combination of two or more thereof.

[0028] In some embodiments, the preservative system comprises a molecule selected from the group consisting of: 3,4-dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N-Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin C (ascorbic acid), Vitamin E (tocopherol), tris(2- carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alpha- cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, 5-sulfosalicylic acid (SSA), trifluoroethanol (TFE), trichloroacetic acid (TCA), and a combination of two or more thereof.

[0029] In some embodiments, the preservative system comprises 5-sulfosalicylic acid and at least one preservative selected from the group consisting of 3,4-dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA), butylatedhydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N- Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin C (ascorbic acid), Vitamin E (tocopherol), tris(2-carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alpha-cyclodextrin, betacyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, trifluoroethanol (TFE), and trichloroacetic acid (TCA).

[0030] In some embodiments, the preservative system comprises ascorbic acid and at least one preservative selected from the group consisting of 3,4-dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N-Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin E (tocopherol), tris(2- carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alpha- cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, 5-sulfosalicylic acid (SSA), trifluoroethanol (TFE), and trichloroacetic acid (TCA).

[0031] In some embodiments, the preservative system comprises ascorbic acid and a- cyclodextrin. In some embodiments, the preservative system comprises ascorbic acid and butylated hydroxy toluene. In some embodiments, the preservative system comprises ascorbic acid and deferoxamine. In some embodiments, the preservative system comprises ascorbic acid and phloroglucinol.

[0032] In some embodiments, the preservative system comprises quercetin and catechin. In some embodiments, the preservative system comprises quercetin and phloroglucinol. In some embodiments, the preservative system comprises BHT and phloroglucinol. In some embodiments, the preservative system comprises quercetin, phloroglucinol, and butylated hydroxy toluene. In some embodiments, the preservative system comprises quercetin, phloroglucinol, butylated hydroxy toluene, SSA, alpha-cyclodextrin, and Vitamin C.

[0033] In some embodiments, the preservative system comprises a combination of preservatives such as the combinations listed in Tables 1-5 and / or Tables 7-9C.

[0034] In some embodiments, the preservative system comprises caffeic acid. In some embodiments, wherein the preservative system comprises phloroglucinol. In some embodiments, the preservative system comprises catechin. In some embodiments, wherein the preservative system comprises quercetin. In some embodiments, wherein the preservative system comprises chlorogenic acid. In some embodiments, wherein the preservative system comprises EDTA. In some embodiments, wherein the preservative system comprises EGCG. In some embodiments, wherein the preservative system comprises BHA. In some embodiments, wherein the preservative system comprises TCA. In some embodiments, wherein the preservative system comprises BHT.

[0035] In some embodiments, the preservative system comprises a preservative listed in any one of Tables 1-5 and / or Tables 7-9C. As an example, Quercetin and Andrographolide, Quercetin and BHT, Quercetin and Catechin, Quercetin and Deferoxamine, Quercetin and Phloroglucinol, and Quercetin and VitC may be used to stabilize one or more of the metabolites listed in Table 1.

[0036] As another example, VitC and a-Cyclodextrin, VitC and BHT, VitC and Deferoxamine, VitC and Phloroglucinol, BHT and Phloroglucinol, and Quercetin and BHT and Phloroglucinol may be used to stabilize one or more of the metabolites listed in Table 2.

[0037] In another example, SSA+ Quercetin + BHT + Phloroglucinol, SSA + Quercetin + BHT, SSA + Quercetin + BHT + Phloroglucinol + VitC + Deferoxamine, SSA + Quercetin + BHT + Phloroglucinol + a-cyclodextrin + VitC, Quercetin + BHT + Phloroglucinol + VitC + Deferoxamine, Quercetin + BHT + Phloroglucinol + a-cyclodextrin + VitC may be used to stabilize one or more of the metabolites listed in Table 3.

[0038] In yet another example, 3,4-dihydroxyphenyl acetic acid, a-Cyclodextrin, Andrographolide, BHA, BHT, Caffeic Acid, and Carvacrol may be used to stabilize one or more of the metabolites listed in Table 4A. In still another example, Catechin, Chlorogenic Acid, EDTA, EGCG, Ethoxyquin, Mannitol, and N-Acetylcysteine (NAC) may be used to stabilize one or more of the metabolites listed in Table 4B. In another example, Nitrogen, Phloroglucinol, Quercetin, 5-sulfosalicylic acid (SSA), Thiamine, Trichloroacetic Acid (TCA), Trolox, and Vitamin C may be used to stabilize one or more of the metabolites listed in Table 4C.

[0039] In yet another example, Quercetin, BHT+Quercetin+Phloroglucinol, SSA+Quercetin, SSA+BHT+Quercetin+Phloroglucinol may be used to stabilize one or more of the lipids listed in Table 5.

[0040] In another example, quercetin, butylated hydroxytoluene, phloroglucinol, A- cyclodextrin, Vitamin C, deferoxamine, 5-sulfosalicyclic acid, and any combination of two or more thereof may be used to stabilize one or more of the cellular metabolites listed in Table 7.

[0041] In another example, quercetin, butylated hydroxytoluene, phloroglucinol, A- cyclodextrin, Vitamin C, deferoxamine, 5-sulfosalicyclic acid, diethylenetriaminepentaacetic acid, catechin, and any combination of two or more thereof may be used to stabilize one or more of the urine metabolites listed in Tables 8A-8D. In yet another example, quercetin, butylated hydroxytoluene, phloroglucinol, A-cyclodextrin, Vitamin C, deferoxamine, 5-sulfosalicyclic acid, diethylenetriaminepentaacetic acid, catechin, and any combination of two or more thereof may be used to enhance the signal of one or more of the metabolites listed in Table 8E-8F.

[0042] In another example, quercetin, butylated hydroxytoluene, phloroglucinol, A- cyclodextrin, Vitamin C, deferoxamine, 5-sulfosalicyclic acid, diethylenetriaminepentaacetic acid, catechin, and any combination of two or more thereof may be used to stabilize one or more of the whole blood metabolites listed in Table 9A-9B. In still another example, quercetin, butylated hydroxytoluene, phloroglucinol, A- cyclodextrin, Vitamin C, deferoxamine, 5-sulfosalicyclic acid, diethylenetriaminepentaacetic acid, catechin, and any combination of two or more thereof may be used to enhance the signal of one or more of the metabolites listed in Table 9C.

[0043] The preservatives used in the present compositions, devices and methods may be used in any concentration that allows for stabilization, improved recovery, and / or signal enhancement of the biological analyte.

[0044] In some embodiments, the preservative is present in a concentration between about 10 pM to 50 mM. As non-limiting examples, quercetin may be present in an amount between about 10 pM to 500 pM, BHT may be present in an amount between about 10 pM to 500 pM, phloroglucinol may be present in an amount between about 10 pM to 500 pM, alpha-cyclodextrin may be present in an amount between about 10 pM to 500 pM, VitaminC may be present in an amount between about 10 pM to 500 pM, deferoxamine may be present in an amount between about 1 mM to 50 mM, SSA may be present in an amount between 0.1% (w / v) to 20% (w / v), DTPA may be present in an amount between about 10 pM to 500 pM, and catechin may be present in an amount between about 10 pM to 500 pM.

[0045] In some embodiments, the preservative is present in a concentration between about10 pM to 500 pM. In some embodiments, the preservative is present in a concentration of about 10 pM, about 20 pM, about 30 pM, about 40 pM, about 50 pM, about 60 pM, about 70 pM, about 80 pM, about 90 pM, about 100 pM, about 110 pM, about 120 pM, about 130 pM, about 140 pM, about 150 pM, about 160 pM, about 170 pM, about 180 pM, about190 pM, about 200 pM, about 210 pM, about 220 pM, about 230 pM, about 240 pM, about250 pM, about 260 pM, about 270 pM, about 280 pM, about 290 pM, about 300 pM, about310 pM, about 320 pM, about 330 pM, about 340 pM, about 350 pM, about 360 pM, about370 pM, about 380 pM, about 390 pM, about 400 pM, about 410 pM, about 420 pM, about430 pM, about 440 pM, about 450 pM, about 460 pM, about 470 pM, about 480 pM, about490 pM, or about 500 pM.

[0046] In some embodiments, the preservative is present in a concentration between about 0.5 mM to 50 mM. In some embodiments, the preservative is present in a concentration of about 0.5 mM, about 1 mM, about 2 mM, about 3 mM, about 4 mM, about 5 mM, about 6 mM, about 7 mM, about 8 mM, about 9 mM, about 10 mM, about 11 mM, about 12 mM, about 13 mM, about 14 mM, about 15 mM, about 16 mM, about 17 mM, about 18 mM, about 19 mM, about 20 mM, about 21 mM, about 22 mM, about 23 mM, about 24 mM, about 25 mM, about 26 mM, about 27 mM, about 28 mM, about 29 mM, about 30 mM, about 31 mM, about 32 mM, about 33 mM, about 34 mM, about 35 mM, about 36 mM, about 37 mM, about 38 mM, about 39 mM, about 40 mM, about 41 mM, about 42 mM, about 43 mM, about 44 mM, about 45 mM, about 46 mM, about 47 mM, about 48 mM, about 49 mM, or about 50 mM.

[0047] In some embodiments, the preservative is present in a concentration between about 0.1% (w / v) to 20% (w / v). In some embodiments, the preservative is present in a concentration between about 0.1% (w / v), about 0.2% (w / v), about 0.3% (w / v), about 0.4% (w / v), about 0.5% (w / v), about 0.6% (w / v), about 0.7% (w / v), about 0.8% (w / v), about 0.9% (w / v), about 1.0% (w / v), about 2.0% (w / v), about 3.0% (w / v), about 4.0% (w / v), about 5.0% (w / v), about 6.0% (w / v), about 7.0% (w / v), about 8.0% (w / v), about 9.0%(w / v), about 10.0% (w / v), about 11.0% (w / v), about 12.0% (w / v), about 13.0% (w / v), about 14.0% (w / v), about 15.0% (w / v), about 16.0% (w / v), about 17.0% (w / v), about 18.0% (w / v), about 19.0% (w / v), or about 20.0% (w / v).

[0048] Provided herein are sample collection devices comprising (e.g., containing, receiving, holding) any one of the preservative systems described herein. The sample collection devices may be used for collecting and analyzing molecules and / or analytes in a biological sample, where the preservative system improves and / or stabilizes the analyte.

[0049] Examples of biological samples that can be used with the sample collection devices include, but are not limited to, blood, plasma, serum, tissues, cells, media, urine, stool, saliva, or a combination of two or more thereof. Biological analytes that may be present in the biological sample include, but are not limited to, a metabolite, a lipid, a nucleic acid, a protein, or a combination of two or more thereof.

[0050] Examples of biological analytes include, but are not limited to, (Hydroxyethyl)methacrylate, l,4,5,6-Tetrahydro-6-oxonicotinic acid, 1,6-Di-O- phosphonohex-2-ulofuranose, 1 -Deoxy -D-altro-heptulose 7-phosphate, l-Pyrroline-2- carboxylic acid, 2-(alpha-D-mannosyl)-D-glyceric acid, 2,3-Bisphospho-D-glyceric acid, 2,3-Dihydryoxybenzoylserine, 2-Aminomuconic acid, 2-Aminomuconic acid semialdehyde, 2'-Deoxycytidine 5'-diphosphate (dCDP), 2'-Deoxyguanosine 5'-triphosphate (dGTP), 2'- Deoxyuridine-5-monophosphate, 2-Furoic acid, 2-Hydroxyadipic acid, 2-Hydroxybutyric acid, 2-Hydroxyglutaric acid, 2-Keto-glutaramic acid, 2-Methylglutaric acid, 2'- Monophosphoadenosine-5'-diphosphoribose, 2-phosphinomethylmalic acid, 2- Phosphogly ceric acid, 2-Propylglutaric acid, 3-(acetamidomethylidene)-2- (hydroxymethyl)succinic acid, 3', 5' cyclic AMP, 3-[hydroxy(oxido)phosphoranyl]pyruvic acid, 3-Dehydro-L-gulonate, 3 -Hydroxybutyric acid, 3 -Hydroxymethylglutaric acid, 3- Methyl pyruvic acid, 3 -Phosphoglyceric acid, 3-Sulfino-alanine, 4,5-Dihydroorotic acid, 4- Hydroxyglutamate semialdehyde, 4-Oxo-proline, 4-phosphoerythronic acid, 4- styrenesulfonic acid, 5-Amino-levulinic acid, 5-Formyl-2-furoic acid, 5-Glutamyl-taurine, 6-Phosphogluconic acid, 7-O-Phosphonohept-2-ulose, Acetic acid, acetyl-CoA, acetyl taurine, Adenine, Adenosine, Adenosine 3 -phosphate 5 -phosphosulfate, Adenosine diphosphate (ADP), Adenosine triphosphate (ATP), Adenylsuccinic acid, ADP -ribose, ADP-ribose l',2'-cyclic phosphate, AICA ribonucleotide, Alanine, AMP, Arabinonic acid, Aspartic acid, aspartyl-L-glutamic acid, ATP, Butedronic acid, Butyric acid, CAR 2:0,CDP, CDP-Ethanolamine, cis-Aconitic acid, Citric acid, ci try 1 -glutamic acid, CMP, Coenzyme A, CTP, Cyclic ADP-ribose, Cysteic acid, Cytidine, dADP, dAMP, dATP, dCDP, dCMP, dCTP, Dehydroascorbic acid, Deoxyadenosine 5'-triphosphate (dATP), Deoxyadenosine diphosphate (dADP), Deoxyribose 5-phosphate, dGDP, dGMP, dGTP, Diacetyl, Diethylpyrocarbonate, dTDP, dTDP-glucose, dTMP, dTTP, dUMP, Erythrose 4- phosphate, Ethyl acetate, FMN, Fructose 1,6-bisphosphate, Fructose 1-phosphate, Fructose2.6-bisphosphate, Fructose 6-phosphate, fucose 1-phosphate, Fumaric acid, Galactaric acid, Galactose 1-phosphate, Galacturonate 1-phosphate, Galacturonic acid, Gallic acid, gamma- Glutamylalanine, gamma-Glutamylglutamic acid, GDP, GDP-mannose, Glu-Asp, Glucaric acid, Gluconic acid, Glucopyranuronic acid, Glucosamine 6-phosphate, Glucose, Glucose1.6-bisphosphate, Glucose 1-phosphate, Glucose 6-phosphate, Glucose- 1,6-bisphosphate, Glucuronic acid, Glucuronic acid 1-phosphate, Glu-Glu, Glutamic acid, Glutamyltaurine, Glutaric acid, Glutathione, Glyceraldehyde 3 -phosphate, Glyceric acid, Glycero-3 - phosphate, Glycero-3 -phosphocholine, Glycero-3 -phosphoethanolamine, Glycero-3 - phosphoinositol, GMP, GTP, Guanosine, Guanosine 5'-diphospho-fucose, Guanosine triphosphate (GTP), Hex-2 -ulose, Hexaric acid, Homocysteinesulfinic acid, Homovanillic acid, Hydroxyacetone phosphate, Hydroxypropanedioic acid, Iditol, IMP, Inositol pentakisphosphate, Isocitric acid, Isovaleric acid, Itaconic acid, Ketoleucine, Lactic acid, Maleamate, Maleic acid, Malic acid, Malonic acid, malonyl-CoA, Mannose 1-phosphate, Mannose 6-phosphate, Methanesulfonic acid, Methanolphosphate, Methylmalonic acid, Myo-inositol hexakisphosphate, N(2)-Formyl-N(l)-(5-phospho-D-ribosyl)glycinamide, N- [3-Carboxy-2-(carboxymethyl)-2-hydroxypropanoyl]glutamic acid, N- Acetyl- 1- aspartylglutamic acid, N-Acetyl-2-aminoadipic acid, N-Acetylanthranilic acid, N- Acetylaspartic acid, N-Acetyl-galactosamine 1-phosphate, N-Acetyl-glucosamine 1- phosphate, N-Acetyl-glucosamine 6-phosphate, N-Acetylglutamic acid, N-acetyl-L-2- aminoadipic acid 6-phosphate, N-Acetyl-mannosamine, N-Acetylmethionine, N- Acetylneuraminic acid, N-Acetylserine, NADPH, N-Carbamoylaspartic acid, N- Formylmethionine, Norfuraneol, Ornithine, Orotic acid, Orotidine, Oxaceprol, Oxalic acid, oxaloacetic acid, oxazolidinone, Oxoglutaric acid, Pantothenic acid, Phosphoadenosine phosphosulfate, Phosphocreatine, Phosphoenolpyruvic acid, Phosphoethanolamine, Phosphonoacetate, phosphopantothenic acid, Phosphoribosyl pyrophosphate, Phosphoric acid, Phosphoserine, Putrescine, Pyridoxal 5'-phosphate, Pyrocatechol, Pyroglutamic acid, Pyrophosphoric Acid, Pyruvic acid, Riboflavin cyclic-4', 5'-phosphate, Ribonic acid, Ribose 1,5 -bisphosphate, Ribose 1-phosphate, Ribose 5-phosphate, Ribulose 5-phosphate, Ribulosediphosphate, Sedoheptulose 1,7-bisphosphate, Sedoheptulose 7-phosphate, Spermidine, Spermine, Succinic acid, Succinic acid semialdehyde, Succinic anhydride, succinyl-CoA, Sulfate, Taurine, Thiosulfic acid, Threonic acid, Thymidine 5'-diphosphate, Thymidine 5'- triphosphate (dTTP), TMP, Trichilin A, UDP, UDP-N-acetylglucosamine, UMP, Uracil, Uric acid, Uridine, UTP, XMP, Xylulose 5-phosphate, and a combination of two or more thereof.

[0051] In some embodiments, the biological sample is a cell, and the biological analyte is selected from the group consisting of a metabolite, a lipid, a nucleic acid, and a protein. Examples of biological analytes in cells include, but are not limited to, 2-aminomuconate, 2-methylglutarate, 3-hydroxymethylglutarate, 4-hydroxy glutamate semialdehyde, acetylcamitine, citryl-glutamate, cysteate, gamma-glutamylalanine (g-Glu-Ala), gammaglutamyltaurine, glutamyl glutamate (Glu-Glu), glutathione, reduced (GSH), homocysteinesulfmate, ketoleucine, N-acetylaspartate, N-acetylglutamate, N- acetylmethionine, N-acetylneuraminate, N-formylmethionine, orotate, orotidine, pantothenate, phosphocreatine, phosphoserine (p-Ser), pyroglutamate (pGlu), taurine, ureidosuccinate, 2-hydroxybutyrate, 3 -hydroxybutyrate, butyrate, glycerylphosphorylethanolamine, O-phosphoethanolamine, 2,3 -diphosphoglycerate, 2- phosphogly cerate, fructose 1,6-bisphosphate, fructose 1 -phosphate, fructose 2,6- bisphosphate, fructose 6-phosphate, glucose, glucose 1 -phosphate, glucose 6-phosphate, glycerol 3 -phosphate, lactate, mannose 1 -phosphate, mannose 6-phosphate, phosphoenolpyruvate, pyruvate, 2'-deoxyadenosine 5'-diphosphate (dADP), 2'- deoxyadenosine 5'-triphosphate (dATP), 2'-deoxycytidine 5'-diphosphate (dCDP), 2'- deoxycytidine 5'-triphosphate (dCTP), 2'-deoxyguanosine 5'-diphosphate (dGDP), 2'- deoxyguanosine 5'-monophosphate (dGMP), 2'-deoxyguanosine 5'-triphosphate (dGTP), 2'- deoxyuridine 5' monophosphate (dUMP), 3 '-deoxythymidine 5'-diphosphate (dTDP), 3'- deoxythymidine 5'-triphosphate (dTTP), adenosine 3'-phosphate 5'-phosphosulfate, adenosine 5 '-diphosphate (ADP), adenosine 5'-monophosphate (AMP), adenosine 5'- triphosphate (ATP), adenyl succinate, ADP -glucose, ADP-ribose, ADP-ribose 2'-phosphate, CDP-ethanolamine, CMP -N-acetylneuraminate, cyclic AMP (cAMP), cytidine 5' monophosphate (CMP), cytidine 5'-diphosphate (CDP), cytidine 5'-triphosphate (CTP), flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN), GDP-mannose, guanosine 5'-diphosphate (GDP), guanosine 5'-monophosphate (GMP), guanosine 5'- triphosphate (GTP), inosine 5'-monophosphate (IMP) / inosinate, nicotinamide adeninedinucleotide, reduced (NADH), pyridoxal 5'-phosphate (P5P), thymidine 5'-diphosphate (TDP), thymidine 5'-monophosphate (TMP), thymidine 5'-triphosphate (TTP), UDP- galactose, UDP -glucose, UDP-N-acetylgalactosamine (UDP-GalNAc), UDP-N- acetylglucosamine (UDP-GlcNAc), urate, uridine, uridine 5'-diphosphate (UDP), uridine 5'- monophosphate (UMP), uridine 5'-triphosphate (UTP), xansthosine 5'-monophosphate (XMP) / xanthylic acid, l-pyrroline-2-carboxylate, 2-hydroxyadipate, 5'-phosphoribosyl-N- formylglycinamide, galactarate, galactose 1 -phosphate, glucarate, glutarate, glycerate, hydroxypropanedioate, maleate, malonate, oxalate, ribonate, threonate, deoxyribose 5- phosphate, erythrose 4-phosphate, gluconate, gluconate 6-phosphate, glucono- 1,5 -lactone, glucono- 1,5 -lactone 6-phosphate, phosphoribosyl pyrophosphate (PRPP), ribose 1,5- bisphosphate, ribose 1 -phosphate, sedoheptulose 1,7-bisphosphate, sedoheptulose 7- phosphate, 2-hydroxy glutarate (2-HG), 2-oxoglutarate (a-KG), aspartate (Asp), cisaconitate, citrate, fumarate, glutamate (Glu), isocitrate, malate, oxaloacetate (OAA), succinate, succinate semialdehyde, and riboflavin cyclic-4', 5'-phosphate. In some embodiments, the biological sample is a cell, and the preservative system comprises quercetin, BHT, phloroglucinol, alpha-cyclodextrin, Vitamin C, deferoxamine, SSA, or a combination of any two or more thereof. In yet another embodiment, the biological sample is a cell, and the preservative system comprises quercetin, BHT, and phloroglucinol.

[0052] In some embodiments, the biological sample is urine, and the biological analyte is selected from the group consisting of a metabolite, a lipid, a nucleic acid, and a protein. Examples of biological analytes in urine include, but are not limited to, 2- Aminoadipic acid, 2-Keto-glutaramic acid, 2-methylcitric acid, 2-Methylglutaric acid, 2-Methylhippuric acid, 2-Pyrrolidone, 2-ureidoglycine, 4-Hydroxy-D-proline, 6-Oxo-pipecolinic acid, Acetylasparagine, Acetylornithine, acetyltaurine, Allantoin, alpha-Aspartyl-4- hydroxyproline, Aminolevulinic acid, asn-val, Aspartic acid, Aspartylaspartic acid, Azelaic acid, CYS-ASP, Cysteine-S-sulfate, Formylisoglutamine, Formylkynurenine, gamma- glutamyltyramine, g-Glutamylcysteine, Glutamate, Glutamine, Glutaurine, Gly-His, Gly- thr, Hippuric acid, Histidine, Histidinol, Homocysteic acid, Hydroxyglutaric acid, Isoleucyl- 4-hydroxyproline, Isovalerylglycine, Levulinic acid, Methionine, N-(lH-Pyrrol-2- ylcarbonyl)glycine, N-(2-Sulfoethyl)alanine, N-(3,4-Dihydroxyphenyl)glutamine, N- Acetylalanine, N-Acetylalloisoleucine, N-Acetylaspartic acid, N-AcetylCitrulline, N- Acetylcysteine, N-Acetylglutamic acid, N-Acetylglutamine, N-Acetylglycine, N- Acetylvaline, N-Formylaspartate, N-Isovalerylglycine, N-Phenylacetylglutamine, N-Propionylmethionine, N-Tigloylglycine, Phenylacetylglycine, Picolinic acid, pyroglutamine, pyroglutamylglycine, Succinyl proline, Taurine, Threonic acid, thr-pro, Thymine, tyramine sulfate, 2,3-Dihydroxypropanoic acid, 2-Butynedioic acid, 2-Oxo-4- pentenoic acid, 3 -Hydroxybutyric acid, 3 -Methylbutanoic acid, 4,5-Dideoxypentonic acid, 4-Hydroxy-2-methylbenzoic acid, 4-Hydroxyphenylacetylglycine, Arachidonic acid, Biacetyl, Capryloylglycine, Cinnamoylglycine, Diacetyl, Ethyl acetate, Ethylmalonic acid, Gamma-Hydroxybutyric acid, Glucoheptonic Acid, Linoleic Acid, Maleamic acid, Maleic acid, Malondialdehyde, Malonic acid, Mevalonic acid, Nitropropionic acid, 2- deoxy glucose, 3 -Ketosucrose, alpha-Methyl D-mannoside, ascorbate 6-phosphate, Ascorbic acid 2-sulfate, Galactonic acid, galactosyl-L-rhamnose, glyceraldehyde 3 -phosphate, glycerin, Glycolic acid, homoserine lactone, Lactic Acid, Mannitol, Mannopyranose, N- glycoloyl-D-mannosaminolactone, Saccharic acid, S-methyl D-thioglycerate, Sucrose, Adenine, cAMP, deoxyuridine, Dihydrothymine, Dihydrouridine, methylxanthine, myoinositol 1,4-bisphosphate, Orotidine, Oxalic acid, Pseudouridine, Uracil, Uric acid, Xanthine, 6-Deoxy-3-O-methyl-beta-D-galactopyranose, 6-O-Sulfo-alpha-D- galactopyranose, Butyryl-L-homoserine lactone, Dihyroxy-lH-indole glucuronide I, N- Acetylgalactosamine 4-sulfate, N-Acetylglucosaminitol, N-Acetylneuraminic acid, Glucopyranuronic acid, Arabic acid, Arabitol, Erythritol, Erythrose, Galacturonic acid, Gluconic acid, Glucono-delta-lactone, glucosone, Glutaconic acid, Xylitol, Ribono-1,4- lactone, Aconitic Acid, Citraconic acid, Citric acid, hydroxycitric acid, Itaconic acid, Pyruvic acid, Succinic acid, Succinic semialdehyde, trans-Aconitic acid, Pantothenic acid, 1,2-Dimethylhydrazine, 2-Anisic acid, 2-Hydroxyhippuric acid, 3-(5-oxoisoxazolin-2-yl)-L- alanine, 3,5-Dihydroxyphenylglycine, 3 -amino- 1 -phenylurea, 3 -Hydroxy-3 -methylglutaric acid, 3-Hydroxyanthranilic acid, 3-Methylhippuric acid, 3-Ribofuranosyluric acid, 3- Sulfamoylalanine, 4- Aminophenol, 4-Aminopyridine, 4-Hydroxy-3- methoxyphenylglycol sulfate, 4-methylthioanisole, 4-Nitroaniline, 4-Oxoproline, 5 -Formyluracil, 5- Heptenoylglycine, 5-Hydroxyindole-3-acetic acid, 5-hydroxyisouric acid, 5-Indolol, 6,7- Dihydropteridine, 6-Aminopyrimidine-2,4,5-triol, 9-Methyluric acid, Allopyranose, clavulanic acid, ethenocytosine, Hept-2-ulose, Isethionic acid, Mesaconic acid, methyl thioacetate, Muconic acid, N-furfurylformamide, Oxalylurea, p-Cresol, Phosphoric acid, Pyrogallol, Pyrogallol-2-O-sulphate, Pyrophosphoric Acid, Quinic acid, Quinolinic acid, Salicyluric acid, Theophylline, Valyl-4-hydroxyproline, Vanillyl mandelic acid, and Xylopyranose. In some embodiments, the biological sample is urine, and the preservative system comprises quercetin, BHT, phloroglucinol, alpha-cyclodextrin, Vitamin C,deferoxamine, SSA, DTP A, catechin, or a combination of any two or more thereof. In yet another embodiment, the biological sample is urine, and the preservative system comprises quercetin, BHT, phloroglucinol, Vitamin C, and deferoxamine.

[0053] In some embodiments, the biological sample is whole blood, and the biological analyte is selected from the group consisting of a metabolite, a lipid, a nucleic acid, and a protein. Examples of biological analytes in whole blood include, but are not limited to, 2- Hydroxyglutaric acid, 2-Keto-glutaramic acid, 3-amino-lH-pyrazolo[4,3-c]pyridine-4,6- diol, 4-Hydroxy-2-oxoglutaric acid, 4-hydroxy-L-glutamate dianion, 4-Hydroxyphenyllactic acid, 4-Methyleneglutamic acid, 4-Nitroaniline, 4-Oxoproline, 5-Imino-L-norvaline, Alanine, Allantoin, alpha-Glutamyl-4-hydroxyproline, alpha-Ketoglutaric acid, Aspartic acid, beta-Aspartylaspartic acid, Cysteine, Cysteinesulfinic acid, Dihydrouridine, N- formylmethionine (fMet), gamma-Glutamyl-N5-acetylomithine, Glutamic acid, Glutamine, Glutamyl-L-glutamine, Glutathione (reduced), Glycine, Gly-pro, Hydroxyglutaric acid, leugin, Levulinic acid, Lysine, Mesaconic acid, N-Acetylalanine, N-Acetylglycine, N-Acetyl- L-aspartic acid, N-Acetyl-L-glutamic acid, N-Formylaspartate, N-Phenylacetylglutamine, Phosphocreatine, Proline, Prolylglycine, S-Lactoylglutathione, S-Sulfocysteine, Tartronic acid, Taurine, Threonic acid, trans-Glutaconic acid, 2,3-Dihydroxypropanoic acid, 2-[(2- Amino-2-carboxyethyl)thio]butanedioic acid, 2-Amino-4-(3-hydroxy-2-oxo-3- azetidinyl)butanoic acid, 2-Butynedioic acid, 2 -Hydroxy valeric acid, 2-Methyl-3- hydroxybutyric acid, 2-Oxo-4-pentenoic acid, 2-Oxobutyric acid, 3,4- dihydroxyphenylacetic acid, 3,4-Methyleneazelaic acid, 3-carboxy-4-methyl-5-propyl-2- furanpropanoic acid (CMPF), 3 -Hydroxy -2, 4-di oxopentyl phosphate, 3-hydroxy-2- methylbutyric acid, 3 -Hydroxy octanoic acid, 3 -Hydroxy valeric acid, 4, 5 -Dihydroxy -2,3- pentanedione, 4-Hydroxybenzoic acid, 4-Hydroxybutyric acid (GHB), 5 -Hydroxy dihydro- 2,3-furandione, 5-Methoxy-3-indoleaceate, 6-Hydroxycaproic acid, 6-Oxohexanoic acid, Beta-Hydroxybutyric acid, diacetyl, Butenedioic acid, cis-2-hydroxypenta-2,4-dienoic acid, Ethylmalonic acid, Glycerophosphoglycerol, Imidazol-4-one-5-propionic acid, Isobutyric acid, Maleic acid, Malondialdehyde, Malonic acid, Pent-2-ulosonic acid, 2,3-Bisphospho- D-gly ceric acid, 3-O-beta-D-galactosyl-sn-glycerol, 3 -phosphoglyceric acid, beta-L-fucose 1 -phosphate, Fructose 1 -phosphate, Glucose, Glucose 1 -phosphate, Glucose- 1,6- bisphosphate, Glyceraldehyde, glyceraldehyde 3-phosphate, Glycerol 3-phosphate, glycolaldehyde phosphate, Glycolic acid, Iditol, Indole-3 -lactic acid, Lactic Acid, Mannitol 1 -phosphate, Phosphoenolpyruvic acid, Saccharolactone, Trehalose, Xylitol, 1-myo-Inositol1 ,2-cyclic phosphate, 2'-Deoxy-5'-inosinic acid, 2'-Deoxy cytidine, 2-Methylhexahydro-4- pyrimidinecarboxylic acid, 2'-monophosphoadenosine-5'-diphosphoribose, Adenine, Adenosine 5'-tetraphosphate, Adenosine triphosphate (ATP), ADP, Allantoin, AMP, ATP, CDP, dADP, Deoxyadenosine 5'-triphosphate (dATP), Deoxyguanosine diphosphate (dGDP), Guanine, Guanosine 5'-diphosphate (GDP), Guanosine monophosphate (GMP), Guanosine triphosphate (GTP), Inosine-5'-monophosphate (IMP), Orotidine, Oxalic acid, Pl,P2-bis(5'-adenosyl) triphosphate, Pseudouridine, Uridine 5'-diphosphate (UDP), UMP, Uracil, Ureidosuccinic acid, Uric acid, 3-ADP-2-phosphoglyceric acid, ADP ribose, ADP- D-ribose l",2"-cyclic phosphate, CDP-ethanolamine, CMP-2-aminoethylphosphonate, Cyclic ADP-ribose, GDP-beta-L-colitose, Guanosine 5'-diphospho-D-mannose, Guanosine 5'-diphospho-B-L-fucose, Mannitol 1 -phosphate, N-Acetyl-D-galactosamine 4-sulfate, N- Acetylglucosamine 1 -phosphate, N-Acetylglucosaminitol, N- Acetylneuraminic acid, N- Acetyl-a-D-glucosamine 1 -phosphate, Saccharolactone, Trehalose, UDP -galactose, UDP- N-acetylglucosamine, udp-glucuronic acid, UDP-N-acetylglucosamine, Uridine 5'- diphosphogalactose, l,3,4-Trihydroxy-5-oxocyclohexanecarboxylic acid, 1- (malonylamino)cyclopropane-l -carboxylic acid, 1,5-Anhydro-D-glucitol, l-Deoxy-5-0- phosphonopent-2-ulose, 1 -deoxy -D-altro-heptulose 7-phosphate, 1 -deoxy -D-threo-hexo- 2,5-diulose 6-phosphate, ID-myo-Inositol 1,2-cyclic phosphate, ID-Myo-inositol 1, 3,4,5- tetrakisphosphic acid, 1-Methyluric acid, 1-O-Phosphonopentitol, 2,3- dihydroxybenzoylserine, 2,6-Diaminopimelic acid, 2-Acetamido-2-deoxy-l,6-di-O- phosphono-beta-D-glucopyranose, 2-Amino-6-(l,2-dihydroxypropyl)-4(lH)-pteridinon, 2- C-methyl-D-erythritol-2,4-cyclopyrophosphate, 2-deoxy-D-gluc-5-ulosonic acid, 2- phosphinom ethylmalic acid, 3-(acetamidomethylidene)-2-(hydroxymethyl)succinic acid, 4- [Amino(carboxy)methyl]-5-oxoproline, 4-Hydroxy-2-butynal, 4-Hydroxyphenyllactic acid, 4-Methoxyaniline, 5 -Hydroxydihydro-2, 3 -furandione, 6-Deoxy-D-arabino-hexos-2-ulose, 6-O-Phosphonohex-2-ulofuranose, Ascorbic acid 2-sulfate, beta-D-Ethyl glucuronide, Crotonic acid, dehydroascorbic acid, Diethylpyrocarbonate, dihydropyranone, Dyphylline, Ethyl sulfate, ethylenediaminetriacetic acid, furoic acid, Glucopyranose, Glucopyranuronic acid, Glycolic acid, Glyoxylic acid, Hexaric acid, Hydroxyglutaric acid, Isethionic acid, Lyxose, monomethyl phosphate, N-ethylmaleimide, Niacin, Nitrilotriacetic acid, ophthalmic acid, oxamate, oxazolidinone, phenyl-D-glucoside, Phosphocreatine, Phosphonoacetate, Phosphoric acid, Pyrogallol, Phosphoerythronic acid, Pyrophosphoric Acid, Tartaric acid, Tartronic acid, 5-O-[Hydroxy(phosphonooxy)phosphoryl]-beta-D- ribofuranose, 5-phospho-alpha-D-ribose cyclic- 1,2-phosphate, 6-O-Phosphono-alpha-D-glucopyranose, 6-O-Phosphono-D-gluconic acid, beta-D-Ethyl glucuronide, beta-D- Glucopyranuronic acid, D-4-phosphoerythronic acid, Erythorbic acid, Erythrose, Erythrose, 4-phosphate, Gluconic acid, Glucono-delta-lactone, Glucosamine 6-phosphate, glucosone, Glutaric acid, Glyoxylic acid, N-glycoloyl-beta-D-glucosamine, phenyl-D-glucoside, Ribonic acid, ribulose 5-phosphate, Sedoheptulose 7-phosphate, Xylose, Xylulose 5- phosphate, 4-Hydroxy-2-oxoglutaric acid, acetopyruvic acid, Aconitic Acid, alpha- Ketoglutaric acid, Citraconic acid, Citric acid, Fumaric acid, Isocitric acid, Itaconic acid, Malic acid, Methyl pyruvate, NADH, NADPH, Pyruvic acid, and Succinic semialdehyde. In some embodiments, the biological sample is whole blood, and the preservative system comprises quercetin, BHT, phloroglucinol, alpha-cyclodextrin, Vitamin C, deferoxamine, SSA, DTP A, catechin, or a combination of any two or more thereof. In another embodiment, the biological sample is whole blood, and the preservative system comprises quercetin, BHT, and phloroglucinol. In yet another embodiment, the biological sample is whole blood, and the preservative system comprises quercetin, BHT, phloroglucinol, and DTPA.

[0054] Suitable sample collection devices for use with the compositions described herein include, but are not limited to, sample collection tubes, capillaries, wearable devices, and dry blood spot collection paper. The type of sample collection device may be optimized for specific metabolites.

[0055] In some embodiments, sample collection tubes comprise polypropylene or a similar material. Sample collection devices can include any of various containers (e.g., tubes) shaped to receive one or more preservatives and analytes to be preserved, including but not limited to fluid and spray-dried forms. The sample collection devices can include or be coupled with one or more caps, seals, and / or evacuation to preserve the stored materials until evaluation, analysis, or other operations.III. Methods

[0056] Provided herein are methods for collecting, recovering, stabilizing, and / or analyzing biological analytes from a biological sample.

[0057] The methods described herein comprise: a) delivering a preservative system into a sample collection device; b) delivering a biological sample to the sample collection device;c) processing the biological sample to obtain a solution containing the biological analyte and debris; and d) collecting the biological analyte.

[0058] In some embodiments, the preservative system is added to the biological sample prior to processing the biological sample. In some embodiments, the preservative system is added to the biological sample after processing the biological sample.

[0059] The preservative system includes an individual preservative or a combination of two or more preservatives described herein.

[0060] Suitable methods for processing the biological sample include typical mechanical techniques including, but not limited to, vortexing, sonication, ceramic bead homogenization, or numerous cycles of aspirate-dispense pipetting. Methods for collecting the biological analyte can include, but are not limited to, centrifuging the solution containing the biological analyte and debris or filtration.

[0061] The collected biological analyte may further be analyzed using known techniques. Such techniques include, but are not limited to, mass spectrometry (MS), which can include ion chromatography-mass spectrometry (IC-MS), hydrophilic interaction chromatography (HILIC)-MS, liquid chromatography-mass spectrometry (LC-MS), gas chromatographymass spectrometry (GC-MS), or capillary electrophoresis-MS (CE-MS). In an embodiment, the collected biological analyte is analyzed using IC-MS. For example, IC-MS can be a useful and / or optimal platform for measuring energy metabolism (e.g., glycolysis, TCA cycle, pentose phosphate pathway, and nucleotide metabolism).

[0062] In some embodiments, the preservative system enhances the signal of the biological analyte during analysis. In some embodiments, the signal of the biological analyte is increased in the presence of the preservative system. The presence of the preservatives not only stabilizes the biological analytes, but also leads to improved assay sensitivity due to the increased signals. Thus, the present compositions, devices, and methods can lead to improved accuracy and sensitivity for measuring the biological analytes.

[0063] In some embodiments, the levels of each analyte are measured over a 24-hour time course. In some embodiments, the levels of each analyte are measured over a 1-hour time course, a 2-hour time course, a 5 -hour time course, a 10-hour time course, a 12-hour time course, a 15-hour time course, an 18-hour time course, a 24-hour time course, a 48-hourtime course, a 1-week time course, a 2-week time course, a 1 -month time course, a 2-month time course, a 3 -month time course, a 4-month time course, a 5 -month time course, a 6- month time course, a 12-month time course, or greater. The levels of analyte can be measured after storing the sample long-term, for example, up to 30 years or even after 30 years in storage.

[0064] The methods and custom sample collection devices may be used for: biobanking (long-term storage of biological samples collected from non-clinical or clinical studies); identifying biomarkers for diagnosing and monitoring the progression of cancer; elucidating the mechanism of action for therapeutic agents; or identifying pharmacodynamic markers of response to therapy.

[0065] The methods and custom sample collection devices described herein yield improved accuracy for the measurement of small molecules (< 2,000 Da) in biological and chemical samples compared to methods and collection tubes that do not use or comprise a preservative system.IV. Preservatives and Preservative Systems for Targeted Stabilization of Analytes

[0066] Suitable classes of preservatives for use in the compositions include, but are not limited to, antioxidants, chelators, inert gases, inert host structures, kosmotropes, protein precipitators, and a combination of two or more thereof.

[0067] Suitable preservatives for use in the compositions include, but are not limited to 3,4- dihydroxyphenylacetic acid, 5-sulfosalicylic acid (SSA), alpha-cyclodextrin, alphatocopherol (vitamin E), alpha-tocotrienol (vitamin E), andrographolide, apigenin, betacyclodextrin, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BEIT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin hydrate, chlorogenic acid, cyanidin, deferoxamine, diethylenetriaminepentaacetic acid (DTP A), epigallocatechin gallate (EGCG), ethoxyquin, ethylenediaminetetraceticacid (EDTA), ferulic acid, gammacyclodextrin, glycerol, gingerol, isomalt, liproxstatin-1 (Lip-1), mannitol, N-acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, sorbitol, trichloroacetic acid (TCA), trifluoroethanol (TFE), tris(2-carboxyethyl)phosphine (TCEP), vitamin Bl (thiamine), vitamin C (ascorbic acid), vitamin C (ascorbyl palmitate), and a combination of two or more thereof.

[0068] In some embodiments, the preservative system comprises 3,4-dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N- Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin C (ascorbic acid), Vitamin E (tocopherol), tris(2-carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alpha-cyclodextrin, betacyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, 5-sulfosalicylic acid (SSA), trifluoroethanol (TFE), trichloroacetic acid (TCA), and a combination of two or more thereof.

[0069] Examples of biological analytes include, but are not limited to, (Hydroxyethyl)methacrylate, l,4,5,6-Tetrahydro-6-oxonicotinic acid, 1,6-Di-O- phosphonohex-2-ulofuranose, 1 -Deoxy -D-altro-heptulose 7-phosphate, l-Pyrroline-2- carboxylic acid, 2-(alpha-D-mannosyl)-D-glyceric acid, 2,3-Bisphospho-D-glyceric acid, 2,3-Dihydryoxybenzoylserine, 2-Aminomuconic acid, 2-Aminomuconic acid semialdehyde, 2'-Deoxycytidine 5'-diphosphate (dCDP), 2'-Deoxyguanosine 5'-triphosphate (dGTP), 2'- Deoxyuridine-5-monophosphate, 2-Furoic acid, 2-Hydroxyadipic acid, 2-Hydroxybutyric acid, 2-Hydroxyglutaric acid, 2-Keto-glutaramic acid, 2-Methylglutaric acid, 2'- Monophosphoadenosine-5'-diphosphoribose, 2-phosphinomethylmalic acid, 2- Phosphogly ceric acid, 2-Propylglutaric acid, 3-(acetamidomethylidene)-2- (hydroxymethyl)succinic acid, 3', 5' cyclic AMP, 3-[hydroxy(oxido)phosphoranyl]pyruvic acid, 3-Dehydro-L-gulonate, 3 -Hydroxybutyric acid, 3 -Hydroxymethylglutaric acid, 3- Methyl pyruvic acid, 3 -Phosphoglyceric acid, 3-Sulfino-alanine, 4,5-Dihydroorotic acid, 4- Hydroxyglutamate semialdehyde, 4-Oxo-proline, 4-phosphoerythronic acid, 4- styrenesulfonic acid, 5-Amino-levulinic acid, 5-Formyl-2-furoic acid, 5-Glutamyl-taurine, 6-Phosphogluconic acid, 7-O-Phosphonohept-2-ulose, Acetic acid, acetyl-CoA, acetyl taurine, Adenine, Adenosine, Adenosine 3 -phosphate 5 -phosphosulfate, Adenosine diphosphate (ADP), Adenosine triphosphate (ATP), Adenylsuccinic acid, ADP -ribose, ADP-ribose l',2'-cyclic phosphate, AICA ribonucleotide, Alanine, AMP, Arabinonic acid, Aspartic acid, aspartyl-L-glutamic acid, ATP, Butedronic acid, Butyric acid, CAR 2:0, CDP, CDP-Ethanolamine, cis-Aconitic acid, Citric acid, ci try 1 -glutamic acid, CMP, Coenzyme A, CTP, Cyclic ADP-ribose, Cysteic acid, Cytidine, dADP, dAMP, dATP,dCDP, dCMP, dCTP, Dehydroascorbic acid, Deoxyadenosine 5'-triphosphate (dATP), Deoxyadenosine diphosphate (dADP), Deoxyribose 5-phosphate, dGDP, dGMP, dGTP, Diacetyl, Diethylpyrocarbonate, dTDP, dTDP-glucose, dTMP, dTTP, dUMP, Erythrose 4- phosphate, Ethyl acetate, FMN, Fructose 1,6-bisphosphate, Fructose 1-phosphate, Fructose2.6-bisphosphate, Fructose 6-phosphate, fucose 1-phosphate, Fumaric acid, Galactaric acid, Galactose 1-phosphate, Galacturonate 1-phosphate, Galacturonic acid, Gallic acid, gamma- Glutamylalanine, gamma-Glutamylglutamic acid, GDP, GDP-mannose, Glu-Asp, Glucaric acid, Gluconic acid, Glucopyranuronic acid, Glucosamine 6-phosphate, Glucose, Glucose1.6-bisphosphate, Glucose 1-phosphate, Glucose 6-phosphate, Glucose- 1,6-bisphosphate, Glucuronic acid, Glucuronic acid 1-phosphate, Glu-Glu, Glutamic acid, Glutamyltaurine, Glutaric acid, Glutathione, Glyceraldehyde 3 -phosphate, Glyceric acid, Glycero-3 - phosphate, Glycero-3 -phosphocholine, Glycero-3 -phosphoethanolamine, Glycero-3 - phosphoinositol, GMP, GTP, Guanosine, Guanosine 5'-diphospho-fucose, Guanosine triphosphate (GTP), Hex-2 -ulose, Hexaric acid, Homocysteinesulfinic acid, Homovanillic acid, Hydroxyacetone phosphate, Hydroxypropanedioic acid, Iditol, IMP, Inositol pentakisphosphate, Isocitric acid, Isovaleric acid, Itaconic acid, Ketoleucine, Lactic acid, Maleamate, Maleic acid, Malic acid, Malonic acid, malonyl-CoA, Mannose 1-phosphate, Mannose 6-phosphate, Methanesulfonic acid, Methanolphosphate, Methylmalonic acid, Myo-inositol hexakisphosphate, N(2)-Formyl-N(l)-(5-phospho-D-ribosyl)glycinamide, N- [3-Carboxy-2-(carboxymethyl)-2-hydroxypropanoyl]glutamic acid, N- Acetyl- 1- aspartylglutamic acid, N-Acetyl-2-aminoadipic acid, N-Acetylanthranilic acid, N- Acetylaspartic acid, N-Acetyl-galactosamine 1-phosphate, N-Acetyl-glucosamine 1- phosphate, N-Acetyl-glucosamine 6-phosphate, N-Acetylglutamic acid, N-acetyl-L-2- aminoadipic acid 6-phosphate, N-Acetyl-mannosamine, N-Acetylmethionine, N- Acetylneuraminic acid, N-Acetylserine, NADPH, N-Carbamoylaspartic acid, N- Formylmethionine, Norfuraneol, Ornithine, Orotic acid, Orotidine, Oxaceprol, Oxalic acid, oxaloacetic acid, oxazolidinone, Oxoglutaric acid, Pantothenic acid, Phosphoadenosine phosphosulfate, Phosphocreatine, Phosphoenolpyruvic acid, Phosphoethanolamine, Phosphonoacetate, phosphopantothenic acid, Phosphoribosyl pyrophosphate, Phosphoric acid, Phosphoserine, Putrescine, Pyridoxal 5'-phosphate, Pyrocatechol, Pyroglutamic acid, Pyrophosphoric Acid, Pyruvic acid, Riboflavin cyclic-4', 5'-phosphate, Ribonic acid, Ribose 1,5 -bisphosphate, Ribose 1-phosphate, Ribose 5-phosphate, Ribulose 5-phosphate, Ribulose diphosphate, Sedoheptulose 1,7-bisphosphate, Sedoheptulose 7-phosphate, Spermidine, Spermine, Succinic acid, Succinic acid semialdehyde, Succinic anhydride, succinyl-CoA,Sulfate, Taurine, Thiosulfic acid, Threonic acid, Thymidine 5'-diphosphate, Thymidine 5'- triphosphate (dTTP), TMP, Trichilin A, UDP, UDP-N-acetylglucosamine, UMP, Uracil, Uric acid, Uridine, UTP, XMP, Xylulose 5-phosphate, and a combination of two or more thereof.

[0070] Further examples of biological analytes include those listed in Tables 1-5, and Tables 7-9C.

[0071] In some embodiments, the biological analyte includes a lipid. Suitable lipids for analysis include, but are not limited, to lipids listed in Table 6.

[0072] In some embodiments, the preservative system comprises ascorbic acid and butylated hydroxy toluene, and the biological analyte is any one of the biological analytes described herein. In some embodiments, the preservative system comprises ascorbic acid and butylated hydroxy toluene, and the biological analyte is selected from the group consisting of 2-hydroxyglutarate, acetylcamitine, adenylsuccinic acid, arabinonic acid, ATP, dATP, beta-citryl-glutamate, citric acid, galactaric acid, glucaric acid, gluconic acid, glycerol 3 -phosphate, dGTP, hydroxypropanedioc acid, lactic acid, mesaconic acid, oxalic acid, phosphoadenosine phosphosulfate, pyruvic acid, TTP, and a combination of two or more thereof.

[0073] In some embodiments, the preservative system comprises ascorbic acid and deferoxamine, and the biological analyte is any one of the biological analytes described herein. In some embodiments, the preservative system comprises ascorbic acid and deferoxamine, and the biological analyte is selected from the group consisting of adenylsuccinic acid, arabinonic acid, ATP, dATP, beta-citryl-glutamate, citric acid, CTP, dCTP, galactaric acid, glucaric acid, gluconic acid, GTP, dGTP, homocysteinesulfmic acid, hydroxypropanedioc acid, lactic acid, mesaconic acid, oxalic acid, phosphoadenosine phosphosulfate, sulfate, TTP, uric acid, UTP, and a combination of two or more thereof.

[0074] In some embodiments, the preservative system comprises ascorbic acid and phloroglucinol, and the biological analyte is any one of the biological analytes described herein. In some embodiments, the preservative system comprises ascorbic acid and phloroglucinol, and the biological analyte is selected from the group consisting of 2- hydroxyglutarate, acetylcamitine, adenylsuccinic acid, arabinonic acid, ATP, dATP, beta- citryl-glutamate, citric acid, galactaric acid, glucaric acid, gluconic acid, dGTP,hydroxypropanedioc acid, lactic acid, mesaconic acid, oxalic acid, phosphoadenosine phosphosulfate, pyruvic acid, TTP, and a combination of two or more thereof.

[0075] In some embodiments, the preservative system comprises quercetin and phloroglucinol, and the biological analyte is any one of the biological analytes described herein. In some embodiments, the preservative system comprises quercetin and phloroglucinol, and the biological analyte is selected from the group consisting of 2- aminomuconic acid semialdehyde, 5'-phosphoribosyl-N-formylglycinamide, 6- phosphogluconic acid, acetylcarnitine, AICAR, cis aconitic acid, dehydroascorbic acid, fumarate, glucose 6-phosphate, erythrose 4-phosphate, glycerol 3 phosphate, itaconate, orotidine, and a combination of two or more thereof.

[0076] In some embodiments, the metabolite is acetyl CoA, and the preservative is caffeic acid. In some embodiments, the metabolite is acetyl CoA, and the preservative is phloroglucinol. In some embodiments, the metabolite is malonyl CoA, and the preservative is caffeic acid. In some embodiments, the metabolite is malonyl CoA, and the preservative is phloroglucinol. In some embodiments, the metabolite is succinyl CoA, and the preservative is caffeic acid. In some embodiments, the metabolite is succinyl CoA, and the preservative is SSA.

[0077] In some embodiments, the metabolite is NADPH, and the preservative is catechin. In some embodiments, the metabolite is NADPH, and the preservative is quercetin.

[0078] In some embodiments, the metabolite is Ornithine, and the preservative is chlorogenic acid. In some embodiments, the metabolite is Ornithine, and the preservative is EDTA.

[0079] In some embodiments, the metabolite is oxaloacetic acid, and the preservative is quercetin. In some embodiments, the metabolite is oxaloacetic acid, and the preservative is EGCG.

[0080] In some embodiments, the metabolite is putrescine, and the preservative is BHA. In some embodiments, the metabolite is putrescine, and the preservative is caffeic acid. In some embodiments, the metabolite is putrescine, and the preservative is TCA.

[0081] In some embodiments, the metabolite is spermidine, and the preservative is caffeic acid. In some embodiments, the metabolite is spermidine, and the preservative is BHT. In some embodiments, the metabolite is spermidine, and the preservative is chlorogenic acid. In some embodiments, the metabolite is spermine, and the preservative is caffeic acid. In some embodiments, the metabolite is spermine, and the preservative is chlorogenic acid.

[0082] In some embodiments, the preservative system comprises quercetin or a combination of preservatives selected from: BHT, quercetin, and phloroglucinol; SSA and quercetin; and SSA, BHT, quercetin, and phloroglucinol, and the biological analyte is a lipid.

[0083] In some embodiments, the preservative system comprises quercetin, BHT, phloroglucinol, alpha-cyclodextrin, Vitamin C, deferoxamine, SSA, or a combination of any two or more thereof. In some embodiments, the preservative system comprises quercetin, BHT, phloroglucinol, alpha-cyclodextrin, Vitamin C, deferoxamine, SSA, DTP A, catechin, or a combination of any two or more thereof.V. Sample Collection Devices

[0084] Suitable sample collection devices for use with the compositions, systems, and methods described herein include, but are not limited to, sample collection tubes, capillaries, wearable devices, dry blood spot collection paper, or any type of collection device used to collect biological samples. The type of sample collection device may be optimized for specific metabolites.

[0085] In some embodiments, sample collection tubes comprise polypropylene or a similar material. Sample collection devices can include any of various containers (e.g., tubes) shaped to receive one or more preservatives and analytes to be preserved, including but not limited to fluid and spray-dried forms. The sample collection devices can include or be coupled with one or more caps, seals, and / or evacuation to preserve the stored materials until evaluation, analysis, or other operations.

[0086] In an aspect, a biological sample is added to the sample collection device, any one of the preservative systems described herein is added to the sample collection device, where the preservative system preserves at least one biological analyte in the biological sample, and the biological sample is processed to isolate the one or more biological analytes.

[0087] In an aspect, provided are kits comprising: a) a sample collection device as described herein, where the sample collection device comprises any one of the preservative systems described herein; and b) instructions for using the sample collection device.VI. Definitions

[0088] As used herein, “about” will be understood by persons of ordinary skill in the art and will vary to some extent depending upon the context in which it is used. If there are uses of the term which are not clear to persons of ordinary skill in the art, given the context in which it is used, “about” will mean up to plus or minus 10% of the particular term.

[0089] The use of the terms “a” and “an” and “the” and similar referents in the context of describing the elements (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the embodiments and does not pose a limitation on the scope of the claims unless otherwise stated. No language in the specification should be construed as indicating any non-claimed element as essential.

[0090] As used herein, the term “metabolite” or “metabolites” refers to small molecules generally less than 2,000 Da and associated with mammalian metabolism. Metabolites may be classified according to metabolite class. Examples of metabolite classes include acetyls, acyclic alkanes, acyl carnitines, aldehydes, amino acids, amino ketones, aralkylamines, benzene and substituted derivatives, tetrapyroIles and derivatives, biphenyls and derivatives, carnitines, cholines, corticosteroids and derivatives, coumarins and derivatives, diacylglycerols, dicarboxylic acids, dipeptides, Eicosanoids, fatty acids (including hydroperoxyl fatty acids, keto- or hydroxy-fatty acids, saturated fatty acids, unsaturated fatty acids, epoxy fatty acids, short-chain fatty acids, medium-chain fatty acids, and long- chain fatty acids), glycerophospholipids, hydroxy acids and derivatives, monosaccharide phosphates, N-acyl-alpha amino acids, phenylpropanoic acids, phosphosphingolipids,azacyclic compounds (for instance pyridines), sphingolipids, sugar alcohols, androgens, estrogens and derivatives (for instance testosterones), and derivatives.

[0091] As used herein, the term “biological sample” refers to a fluid, tissue, or other material collected from a subject. Examples of biological samples can include but are not limited to, blood, serum, plasma, saliva, urine, gastric fluid, cerebrospinal fluid, stool, mucus, sweat, interstitial fluids derived from tumorous tissue, ocular fluids, biopsy tissue, cultured cells, and other secretions or excretions. The sample may be obtained from a human or animal. The sample may be obtained from a living or dead subject.

[0092] Various embodiments are described hereinafter. It should be noted that the specific embodiments are not intended as an exhaustive description or as a limitation to the broader aspects discussed herein. One aspect described in conjunction with a particular embodiment is not necessarily limited to that embodiment and can be practiced with any other embodiment(s).

[0093] The present disclosure, thus generally described, will be understood more readily by reference to the following examples, which are provided by way of illustration and are not intended to be limiting of the present disclosure.EXAMPLES

[0094] While certain embodiments have been illustrated and described, it should be understood that changes and modifications can be made therein in accordance with ordinary skill in the art without departing from the technology in its broader aspects as defined in the following claims.

[0095] Example 1. Effects of selected preservatives on the stabilization and / or recovery of biological analytes

[0096] FIGs. 1A-1D demonstrate the effects of selected preservatives on the stabilization and / or recovery of selected analytes. Putrescine (FIG. 1A, analyzed using HILIC-MS), deoxycytidine triphosphate (dCTP) (FIG. IB, analyzed using IC-MS), fumarate (FIG. 1C, analyzed using IC-MS), and galactaric acid (FIG. ID, analyzed using IC-MS), are examples of unstable analytes or poorly recovered / ionized analytes that are not stabilized by most of the preservatives tested but are stabilized using a specific combination of preservatives.

[0097] Putrescine is not stabilized by the preservatives tested. Deoxycytidine triphosphate (dCTP) is stabilized by the addition of vitamin C + deferoxamine. Fumarate is stabilized bythe addition of BHT + phloroglucinol but none of the other preservatives included in this test. Galactaric acid appears to be a dark metabolite (undetected) under preservative-free conditions, and its signal is increased significantly by the addition of a number of preservative combinations. These examples illustrate the challenges and non-obvious aspects of stabilizing small molecule analytes.

[0098] Analysis of Polar metabolites by IC-MS

[0099] A 70% confluent T-225 flask of MCF-7 cells was washed twice with PBS, trypsinized, and counted. One million cells were seeded in each 10-cm dish, allowed to attach for 45-min in a vibration-free environment, then transferred to a 37°C incubator at 90% relative humidity for 48 h to allow trypsin-induced artifacts to subside. Dishes were then harvested one-at-a-time as follows. Medium was aspirated, 200 pL extraction solvent was added, cells were scraped and transferred to a methanol-washed microfuge tube with a pipettor, and extracts were centrifuged at 20,000 g for 10 min at 4°C. Extraction solvents consisted of ice-cold 80 / 20 (v / v) methanol / water containing 0.1% ammonium hydroxide and indicated preservatives at 100 pM. After centrifugation of the extracts, supernatants were transferred to injection vials, and 10 pL was injected for analysis by ion chromatography (IC)-MS. IC mobile phase A (MPA; weak) was water, and mobile phase B (MPB; strong) was water containing 100 mM KOH. A Thermo Scientific Dionex ICS- 6000+ system included a Thermo lonPac ASH column (4 pm particle size, 250 x 2 mm) with column compartment kept at 30°C. The autosampler tray was chilled to 4°C. The mobile phase flow rate was 360 pL / min, and the gradient elution program was: 0-5 min, 1% MPB; 5-25 min, 1-35% MPB; 25-39 min, 35-99% MPB; 39-49 min, 99% MPB; 49-50, 99- 1% MPB. The total run time was 50 min. To assist the desolvation for better sensitivity, methanol was delivered by an external pump and combined with the eluent via a low dead volume mixing tee. Data were acquired using a Thermo Orbitrap Fusion Tribrid Mass Spectrometer under ESI negative ionization mode at a resolution of 240,000. Raw data files were imported to Skyline software for final analysis.

[0100] Analysis of Polar metabolites by HILIC-MS

[0101] A 70% confluent T-225 flask of MCF-7 cells was washed twice with PBS, trypsinized, and counted. One million cells were seeded in each 10-cm dish, allowed to attach for 45-min in a vibration-free environment, then transferred to a 37 C incubator at90% relative humidity for 48 h to allow trypsin-induced artifacts to subside. Dishes were then harvested one-at-a-time as follows. Medium was aspirated, 200 pL extraction solvent was added, cells were scraped and transferred to a methanol-washed microfuge tube with a pipettor, and extracts were centrifuged at 20,000 g for 10 min at 4°C. Extraction solvents consisted of ice-cold 80 / 20 (v / v) methanol / water containing 0.1% ammonium hydroxide and indicated preservatives at 100 pM. After centrifugation of the extracts, supernatants were transferred to injection vials and diluted in 90% acetonitrile (v / v) containing 1% formic acid, of which 15 pL was injected on a Vanquish LC System (Thermo Scientific). HILIC mobile phase A (MPA) was 95 / 5 (v / v) water / acetonitrile containing 20 mM ammonium acetate and 20 mM ammonium hydroxide (pH~9), and mobile phase B (MPB) was acetonitrile. The stationary phase was a Waters Xbridge BEH Amide column (3.5 pm particle size, 100 x 4.6 mm) with column compartment kept at 30°C. The autosampler tray was chilled to 4°C. The mobile phase flow rate was 300 pL / min, and the gradient elution program was: 0-3 min, 85% MPB; 3-10 min, 85-30% MPB; 10-20 min, 30-2% MPB; 20-25 min, 2% MPB; 26-30 min, 2-85% MPB. The total run time was 30 min.

[0102] Example 2. Custom blood collection tubes reveal potential under-treatment of patients with L-asparinginase

[0103] A custom blood collection device was prepared to stabilize the amino acid asparagine long enough to be measured accurately in the blood of childhood leukemia patients treated with L-asparaginase, an enzyme that targets asparagine. Regulatory agencies have provided exemption to manufacturers of L-asparaginase from performing pharmacodynamic studies in patients due to the well-known rapid degradation of asparagine (the pharmacodynamic marker) ex vivo by L-asparaginase. There was reason to suspect that many of those children may exhibit non-durable depletion of asparagine and, therefore, would benefit from a different L-asparaginase dosing schedule. Indeed, non-durable depletion of asparagine is observed in those patients (FIG. 2), and that finding has prompted new clinical trials to test the hypothesis that durable depletion of asparagine will produce better outcomes.

[0104] Whole blood from patients treated with two different variants of L-asparaginase (Oncaspar or Erwinaze) was collected into tubes containing a preservative that stabilizes asparagine (Asn), which was measured by LC-MS. The goal of L-asparaginase therapy is to achieve durable depletion of asparagine during the treatment window, but the resultsindicate non-durable depletion of Asn in half of the patients (most clearly illustrated in patients 4 and 6, FIG. 2). These results prompt the need for new clinical trials to the optimize treatment regimen. Although L-asparaginase has been FDA-approved since 1978, the instability of Asn in the presence of L-asparaginase in samples from L-asparaginase- treated patients prevented the scientific community from discovering this phenomenon of insufficient Asn depletion and its prevalence.

[0105] Example 3. Metabolite Preservation Using Single Preservatives and a Combination of Preservatives

[0106] The tables below show the impact of different preservative systems on metabolite signals, which are associated with the analyte’s stability, ionization efficiency, and / or recovery. Metabolites (including lipids) were extracted from MCF7 cells with the indicated preservatives, and polar metabolite profiling was performed by IC-MS and LC(HILIC)-MS, and lipid profiling was performed by LC(C30)-MS. The methods used to extract the metabolites and the methods used for profiling are similar to the methods used in Example1. The methods for analyzing lipids are described below.

[0107] The numeric values represent analyte preservation calculated as [AUC]24-h divided by [AUC]0-h in the no-preservative group.

[0108] Analysis of lipids by LC(C30)-MS

[0109] A 70% confluent T-225 flask of MCF-7 cells was washed twice with PBS, trypsinized, and counted. One million cells were seeded in each 10-cm dish, allowed to attach for 45-min in a vibration-free environment, then transferred to a 37°C incubator at 90% relative humidity for 48 h to allow trypsin-induced artifacts to subside. Dishes were then harvested one-at-a-time as follows. Extraction solvent consisted of ethanol containing 100 pM indicated preservative in methanol and 2% Avanti SPLASH LIPIDOMIX Mass Spec Standards, pre-cooled to -80°C. Medium was aspirated, 200 pL extraction solvent was added, cells were scraped and transferred to a methanol-washed microfuge tube with a pipettor. The tubes were vortexed for 2 min then centrifuged at 4°C for 10 min at 17,000 g. After centrifugation of the extracts, supernatants were transferred to glass injection vials, and 10 pL was injected on a Vanquish LC System (Thermo Scientific). Mobile phase A was 40:60 acetonitrile: 0.1% formic acid in 10 mM ammonium formate. Mobile phase B (MPB) was 90:9: 1 isopropanol: acetonitrile: 0.1% formic acid in 10 mM ammonium formate. Thestationary phase was a Thermo Fisher Scientific Accucore C30 column (2.6 pm, 150 * 2.1 mm) maintained at 40°C. The autosampler tray was chilled to 4°C. The mobile phase flow rate was 200 pL / min, and the gradient elution program was: 0 to 3 min, 30% MPB; 3 to 13 min, 30 to 43% MPB; 13.1 to 33 min, 50 to 70% MPB; 33 to 48 min, 70 to 99% MPB; 48 to 55 min, 99% MPB; 55.1 to 60 min, 30% MPB.Table 1. Metabolite Preservation Using Quercetin and Andrographolide, Quercetin and BHT, Quercetin and Catechin, Quercetin and Deferoxamine, Quercetin and Phloroglucinol, and Quercetin and VitCTable 2. Metabolite Preservation Using VitC and a-Cyclodextrin, VitC and BHT, VitC and Deferoxamine, VitC and Phloroglucinol, BHT and Phloroglucinol, and Quercetin and BHT and PhloroglucinolTable 3. Metabolite Preservation Using SSA+ Quercetin + BHT + Phloroglucinol, SSA + Quercetin + BHT, SSA + Quercetin + BHT + Phloroglucinol + VitC + Deferoxamine, SSA + Quercetin + BHT + Phloroglucinol + a-cyclodextrin + VitC, Quercetin + BHT + Phloroglucinol + VitC + Deferoxamine, Quercetin + BHT + Phloroglucinol + a- cyclodextrin + VitCTable 4A. Metabolite Preservation Using 3,4-dihydroxyphenyl acetic acid, a-Cyclodextrin, Andrographolide, BHA, BHT, Caffeic Acid and CarvacrolTable 4B. Metabolite Preservation Using Catechin, Chlorogenic Acid, EDTA, EGCG,Ethoxyquin, Mannitol, and N-Acetylcysteine (NAC)Table 4C. Metabolite Preservation Using Nitrogen, Phloroglucinol, Quercetin, 5- sulfosalicylic acid (SSA) Thiamine, Trichloroacetic Acid (TCA) Trolox, and Vitamin CTable 5. Lipid preservation using Quercetin, BHT+Quercetin+Phloroglucinol, SSA+Quercetin, SSA+BHT+Quercetin+PhloroglucinolTable 6, Lipid class and subclass abbreviations[HO] Tables 1-4C present a list of 255 polar metabolites that were extracted from MCF7 cells with or without preservatives and measured by ion chromatography-mass spectrometry (IC-MS) or liquid chromatography with hydrophilic interaction chromatography, LC(HILIC)-MS. Table 5 presents a list of 969 lipids that were extracted from MCF7 cells with or without preservatives and measured by LC(C30)-MS. The organization of metabolite(s) and / or preservative(s) into tables / sub-tables does not imply a specific relationship amongst such materials.[Hl] The numeric value represents analyte preservation calculated as the level of analyte measured at the final time point in the experiment (generally t=24 h, but for a few experiments the final time point was between 12-20 h) divided by the level of analyte measured at t=0 in the no-preservative condition. A value of 0 indicates complete instability, a value of 1 indicates perfect preservation, and a value larger than 1 indicates that the preservative positively modulated recovery, ionization efficiency, or both. For example, for the metabolite phosphoenolpyruvic acid, which is completely unstable without a preservative as indicated by the “0” value, several preservatives effectively stabilized this metabolite — BHT + phloroglucinol (1.64), vitamin C + deferoxamine (1.06), quercetin + BHT (1.33), quercetin + phloroglucinol (1.47), and quercetin + BHT + phloroglucinol (3.47). The 3.47 value yielded by quercetin + BHT + phloroglucinol indicates that thiscombination of preservatives not only stabilizes phosphoenolpyruvic acid but also increases its signal by 247%, likely due to improved ionization efficiency and / or improved recovery imparted by this specific combination of preservatives.

[0112] 89 polar metabolites exhibited 50% or greater degradation within 24 h without a preservative: Phosphoenolpyruvic acid, Oxaloacetic acid, Phosphoribosyl pyrophosphate, 2,3-Diphosphoglyceric acid, Deoxyadenosine 5'-phosphate (dAMP), Deoxy cytidine 5'- phosphate (dCMP), 3 -Phosphoglyceric acid, Deoxythymidine 5'-phosphate (dTMP), Sedoheptulose 1,7-bisphosphate, Inosine 5'-phosphate (IMP), Fructose 1 -phosphate, Erythrose 4-phosphate, Glycero-3 -phosphocholine, Itaconic acid, AICAR, Malic acid, Glucose 1,6-bisphosphate, Glycerol 3-phosphate, 2'-Deoxycytidine 5'-diphosphate (dCDP), (Hydroxy ethyl)methacrylate, Cysteic acid, 5-Glutamyl-alanine, l,6-Di-O-phosphonohex-2- ulofuranose, Cyclic AMP (cAMP), Ornithine, Hydroxypropanedioic acid, Thiosulfic acid, Ribulose diphosphate, 4-phosphoerythronic acid, Fumaric acid, Succinyl-CoA, Adenine, Lactic acid, Riboflavin cyclic-4', 5'-phosphate, Orotidine, Deoxycytidine 5'-diphosphate (dCDP), Uridine, Flavin Mononucleotide (FMN), N-Acetylneuraminic acid, gamma- Glutamylglutamic acid, Deoxyribose 5-phosphate, Glyceraldehyde 3-phosphate, Phosphonoacetate, cytidine 5'-phosphate (CMP), Galacturonic acid, Deoxycytidine 5'- triphosphate (dCTP), Oxalic acid, NADPH, GDP -mannose, O-Phosphoethanolamine, Glucose 6-phosphate, Phosphoserine, 3 -Methyl pyruvic acid, Glycero-3 - phosphoethanolamine, Hydroxyacetone phosphate, UDP -galactose, Uric acid, Adenosine 5'- phosphate (AMP), Deoxyguanosine 5'-phosphate (dGMP), Putrescine, Mannose 1- phosphate, Spermine, 3 -Hydroxybutyric acid, Mannose 6-phosphate, N- Acetylmethionine, Deoxyadenosine 5'-diphosphate (dADP), Orotic acid, Aspartic acid, Pyruvic acid, Taurine, Gluconic acid, Spermidine, Ureidosuccinic acid, Deoxyadenosine 5'-triphosphate (dATP), N-Formylmethionine, Galactaric acid, Thymidine 5'-phosphate (TMP), Glutathione, Ribose 5-phosphate, Pantothenic acid, Glucaric acid, Glucuronic acid, Glucose, Sulfate, Malonic acid, 2-Aminomuconic acid semialdehyde, Glucose 1 -phosphate, CDP -Ethanolamine, and Glyceric acid. Of those, 74 (83%) were able to be stabilized and / or recovered to a fraction of 0.90 (90%) or better. Of the full list of 255 metabolites detected, 224 (88%) were able to be stabilized and / or recovered to a fraction of 0.90 (90%) or better. Based on the number of metabolites that could be stabilized and / or recovered to a fraction of 0.90 (90%) or better, the best preservatives for polar metabolites appeared to be quercetin + BHT + phloroglucinol, quercetin + phloroglucinol, and quercetin + catechin.

[0113] Oxaloacetic acid is a difficult metabolite to measure accurately and, consequently, is rarely reported in the scientific literature. Unexpectedly, single-agent preservatives carvacrol, EGCG, mannitol, alpha-cyclodextrin, and quercetin all successfully stabilized and / or recovered oxaloacetic acid to a fraction of 0.90 or better. The most effective preservative combination was SSA + quercetin + BHT, which yielded preservation to a fraction of 1.29.

[0114] NADH, NADPH, and glutathione (reduced) are also highly unstable due to their roles as reducing equivalents in redox metabolism; reactive oxygen species, reactive nitrogen species, and even the oxygen in the sample collection tube can oxidize NADH, NADPH, and glutathione. The phloroglucinol-containing combinations were highly effective for NADPH — quercetin + phloroglucinol (2.82), quercetin + BHT + phloroglucinol (5.96), and BHT + phloroglucinol (17.34). BHT- and quercetin-containing preservatives effectively preserved glutathione — SSA + quercetin + BHT (0.93), quercetin + catechin (1.06), BHT + phloroglucinol (0.96), vitamin C + BHT (0.96), quercetin + phloroglucinol (1.15), and quercetin + BHT + phloroglucinol (1.10). The ability to accurately measure at least two of these central redox metabolites will enable new research in redox metabolism.

[0115] Glycolysis is a key energy metabolism sub-pathway associated with the following metabolites that were detected: 2,3-Diphosphoglyceric acid, 2-Mannosyl-glyceric acid, 2- Phosphoglyceric acid, 3-[hydroxy(oxido)phosphoranyl]pyruvic acid, 3-Methyl pyruvic acid, 3 -Phosphoglyceric acid, Fructose 1,6-bisphosphate, Fructose 1-phosphate, Fructose 2,6- bisphosphate, Fructose 6-phosphate, Glucose, Glucose 1,6-bisphosphate, Glucose 1- phosphate, Glucose 6-phosphate, Glyceraldehyde 3 -phosphate, Glyceric acid, Glycerol 3- phosphate, Hydroxyacetone phosphate, Lactic acid, Mannose 1-phosphate, Mannose 6- phosphate, Phenylpyruvic acid, Phosphoenolpyruvic acid, and Pyruvic acid. The vast majority of those metabolites were highly unstable. The most effective preservatives for those analytes were quercetin + catechin and quercetin + phloroglucinol; these two combinations stabilized and / or recovered 18 of 24 glycolysis-associated metabolites to a fraction of 0.90 (90%) or better.

[0116] The tricarboxylic acid (TCA) cycle is another major energy metabolism subpathway and is associated with the following metabolites that were detected: Acetyl-CoA, Malonyl-CoA, Succinyl-CoA, 2-Oxoglutaric acid (alpha-ketoglutaric acid), 4-Hydroxyglutamate semialdehyde, 4-Hydroxyglutamate semialdehyde, ci try 1 -glutamic acid, FAD, Flavin Mononucleotide (FMN), NADH, Pantothenic acid, Phosphopantothenic acid, Riboflavin cyclic-4', 5'-phosphate, 2-Hydroxyglutaric acid, 2-Keto-glutaramic acid, 2- Methylglutaric acid, 2-Propylglutaric acid, 3-(acetamidomethylidene)-2- (hydroxymethyl)succinic acid, 3 -Hydroxymethylglutaric acid, Adenylsuccinic acid, cis- Aconitic acid, Citric acid, Coenzyme A, Fumaric acid, Isocitric acid, Isovaleric acid, Itaconic acid, Malic acid, Oxaloacetic acid, Succinic acid, Succinic acid semialdehyde, Succinic anhydride, Ureidosuccinic acid. With only a few exceptions, most of those metabolites were found to be unstable, with median recovery of 0.67. As with the glycolysis pathway, the most effective preservatives for those analytes were quercetin + catechin and quercetin + phloroglucinol; these two combinations stabilized and / or recovered 11 of 33 TCA cycle-associated metabolites to a fraction of 0.90 (90%) or better. Notably, within the array of preservative combinations tested, 26 of 33 TCA cycle-associated metabolites could be stabilized and / or recovered to a fraction of 0.90 or better.

[0117] The pentose phosphate pathway is another major energy metabolism sub-pathway and is associated with the following metabolites that were detected: NADPH, 6- Phosphogluconic acid, Erythrose 4-phosphate, Ribose 1,5 -bisphosphate, Ribose 1- phosphate, Ribose 5-phosphate, Ribulose 5-phosphate, Ribulose diphosphate, Sedoheptulose 1,7-bisphosphate, and Sedoheptulose 7-phosphate. Eight of those ten metabolites were found to be unstable, with median recovery of 0.51. Five preservative combinations were highly effective for those analytes: quercetin + BHT, quercetin + catechin, quercetin + phloroglucinol, BHT + phloroglucinol, quercetin + BHT + phloroglucinol; these five combinations together stabilized and / or recovered 10 of 10 pentose phosphate pathway-associated metabolites to a fraction of 0.90 (90%) or better. The two best preservative systems were quercetin + phloroglucinol and quercetin + BHT + phloroglucinol, each of which yielded preservation greater than or equal to 0.90 for 8 of the 10 analytes.

[0118] Nucleotide metabolism is another major sub-pathway and is associated with the following metabolites that were detected: Xylulose 5-phosphate, ADP-glucose, ADP -ribose, ADP-ribose l',2'-cyclic phosphate, ADP-ribose 2'-phosphate, CMP-N-acetylneuraminic acid, Cyclic ADP-ribose, dTDP-glucose, GDP-mannose, Guanosine 5'-diphospho-fucose, UDP-galactose, UDP -glucose, UDP-N-acetylgalactosamine, UDP-N-acetylglucosamine,Guanosine 5'-diphosphate (GDP), Guanosine 5'-triphosphate (GTP), 2'- Monophosphoadenosine-5'-diphosphoribose, 3', 5' cyclic AMP, 4,5-Dihydroorotic acid, Adenine, Adenosine, Adenosine 3-phosphate, 5 -phosphosulfate, Adenosine 5'-diphosphate (ADP), Adenosine 5'-phosphate (AMP), Adenosine 5'-triphosphate (ATP), AICAR, Cyclic AMP (cAMP), Cytidine, cytidine 5'-diphosphate (CDP), cytidine 5'-phosphate (CMP), cytidine 5'-triphosphate (CTP), Deoxyadenosine 5'-diphosphate (dADP), Deoxyadenosine 5'-phosphate (dAMP), Deoxyadenosine 5'-triphosphate (dATP), Deoxycytidine 5'- diphosphate (dCDP), Deoxy cytidine 5'-phosphate (dCMP), Deoxy cytidine 5'-triphosphate (dCTP), Deoxyguanosine 5'-diphosphate (dGDP), Deoxyguanosine 5'-phosphate (dGMP), Deoxyguanosine 5'-trphosphate (dGTP), Deoxyribose 5-phosphate, Deoxythymidine 5'- diphosphate (dTDP), Deoxythymidine 5'-phosphate (dTMP), Deoxythymidine 5'- triphosphate (dTTP), Deoxyuridine 5'-diphosphate (dUDP), Deoxyuridine 5'-phosphate (dUMP), Diadenosine triphosphate, Guanosine, Guanosine 5'-phosphate (GMP), Inosine 5'- phosphate (IMP), Orotic acid, Orotidine, Phosphoadenosine phosphosulfate, Phosphoribosyl pyrophosphate, Thymidine 5'-diphosphate (TDP), Thymidine 5'-phosphate (TMP), Thymidine 5'-triphosphate (TTP), Uracil, Uridine, Uridine 5'-diphosphate (UDP), Uridine 5'-phosphate (UMP), Uridine 5'-triphosphate (UTP), Xanthosine 5'-phosphate (XMP). The majority of those 63 nucleotide metabolism-associated metabolites were found to be stable, with median recovery of 0.78. Nevertheless, 22 nucleotide metabolism- associated metabolites exhibited stability / recovery below 0.50 — Phosphoribosyl pyrophosphate, Deoxyadenosine 5'-phosphate (dAMP), Deoxycytidine 5'-phosphate (dCMP), Deoxythymidine 5'-phosphate (dTMP), Inosine 5'-phosphate (IMP), AICAR, Cyclic AMP (cAMP), Adenine, Orotidine, Deoxycytidine 5'-diphosphate (dCDP), Uridine, Deoxyribose 5-phosphate, cytidine 5'-phosphate (CMP), Deoxycytidine 5'-triphosphate (dCTP), GDP-mannose, UDP-galactose, Adenosine 5'-phosphate (AMP), Deoxyguanosine 5'-phosphate (dGMP), Deoxyadenosine 5'-diphosphate (dADP), Orotic acid, Deoxyadenosine 5'-triphosphate (dATP), Thymidine 5'-phosphate (TMP). One preservative combination that was particularly effective for those analytes was quercetin + phloroglucinol, which stabilized and / or recovered 13 of 22 of those analytes to a fraction of 0.90 or better. Another effective preservative was quercetin + catechin, which stabilized and / or recovered 11 of 22 of those analytes to a fraction of 0.90 or better. Overall, the full set of screened preservatives yielded stabilization and / or recovery of 20 of those 22 analytes to a fraction of 0.90 or better.

[0119] 158 lipids exhibited 50% or greater degradation without a preservative: CAR 18:1, Cer 18:0;02 / 24:0, Cer 18:l;O2 / 16:0, Cer 18:2;O2 / 16:0, Cer 18:2;O2 / 24:l, Cer(dl8:l_23:l)+2O:(s), Cer(d20:l_23:l)+2O:(s), Cholesterol, DG 18:1 18:1, HexlCer(dl8:2_24:0)+O:(s), HexCer 18:l;O2 / 22:l, LPC 14:0, LPC 16:0, LPE 18:1, LPE 24:1, PA 18:0 18:1, PC 14:0_15:0, PC 14:0_16:0, PC 15:0 18:1, PC 16:0 17:1, PC 16:0 18:1, PC 16:0_20:l, PC 16:0_20:3, PC 16:0_20:4, PC 16:0_24:4, PC 16:1 16:3, PC 16:1 17:1, PC 16:1_22:6, PC 17:0 18:1, PC 18:0 18:1, PC 18:1 / 18:1, PC 18: 1 18:2, PC 18:1 19:1, PC 18: 1 19:4, PC 18:1_24:2, PC 18:1_24:4, PC 20:l_20:4, PC 20:l_24:5, PC 32:4, PC 33:2, PC 38:7, PC 40:1, PC 42:3, PC 44:1, PC 0-16:0 / 18:1, PC 0-24:0 / 22:3, PC(15:2_20:l), PC(16:0_26:7), PC(18:1_24:2), PE 16:1 18:0, PE 16:l_20:4, PE 18:0_20:2, PE 18:0_20:3, PE 18:0_20:5, PE 18:0_22:2, PE 18:0_22:4, PE 18:0_22:6, PE 18:1 / 18:1, PE 18: 1 20: 1, PE 18:l_20:2, PE 18:l_20:4, PE 18: 1 20:5, PE 18: 1 22: 1, PE 18:1_22:7, PE 18:l_24:0, PE 18: 1 26: 1, PE 20:0_20:4, PE 20:4_22:l, PE 20:4_24:0, PE P-16:0 / 18: 1, PG 18:0 18:1, PI 16:1 18:0, PI 18:0 18:1, PI 18:020:2, PI 18:020:4, PS 18:0 18:2, PS 18:0 19:1, PS 18:0_20:0, PS 18:0_20:3, PS 18:0_20:4, PS 18:1 / 18:1, PS 18: 1 20: 1, PS 18:1 22:1, SM33:1;O2, SM36:1;O2, SM 42:2;O2, SM(d36:2)+D9:(s), TG 10:0 16: 1 18: 1, TG 14:0_14:0_16:0, TG 14:0_16:l_20:4, TG 14: 1 16: 1 18: 1, TG 15:0 16:1 18:0, TG 16:0 17: 1 18: 1, TG 16:0 18:0 18:0, TG 16:0 18:0 18:1, TG 16:0 18:0 19:1, TG 16:0 18:022:0, TG 16:0 18: 1 18: 1, TG 16:0 18:1 20:1, TG 16:0_18:l_20:2, TG 16:0 18: 1 20:5, TG 16:0_18:l_22:0, TG 16:0_18:l_24:0, TG 16:0 18:1 24:1, TG 16: 1 17:0 18:0, TG 16:1 18:1 18:2, TG 16:1 18:1 20:1, TG 16: 1 18: 1 20:2, TG 16: 1 18: 1 22:0, TG 16: 1 18: 1 24:2, TG 16: 1 18: 1 24:5, TG 17:1 18:0 18:0, TG 18:0 / 18:0 / 18:0, TG 18:0_18:0_20:0, TG 18:0 18: 1 18: 1, TG 18:0 18: 1 18:2, TG 18:0 18:1 20:1, TG 18:0_18:l_20:2, TG 18:0 18: 1 20:5, TG 18:0 18:1 22:1, TG 18:0_18:l_22:2, TG 18:0 18:1 26:1, TG 18:0 18:221:1, TG 18:1 18:1 18:2, TG 18:1 18:1 20:1, TG 18:1 18:1 21:1, TG 18:1 18:1 22:1, TG 18: 1 18: 1 24:6, TG 18: 1 18:224: 1, TG 18:l_20:l_22:4, TG 18: 1 20: 1 26: 1, TG 20:l_20:2_22:l, TG50:3_16:0, TG 0-13:0_18:1_3:0, TG 0-15:0_16:1_3:0, TG O- 15:0 18:1 3:0, TG 0-15:0_20:1_3:0, TG 0-15:0_20:4_3:0, TG(16:1_18:1_24:2), TG(18: 1 18: 1 21 : 1), TG(18:0_18:2_21:l), TG(18: 1 18: 1 28: 1), TG(4:0_4:0_18:l)+00:(s), TG(16:0_24:1_14:2)+O:(s), TG 0-13:0_18:1_3:0, TG O- 15:0 16:1 3:0, TG 0-15:0 18:1 3:0, TG 0-15:0_20:1_3:0, TG 0-15:0_20:4_3:0. The most effective preservatives for those analytes were SSA + quercetin and SSA + BHT + quercetin + pholoroglucinol, which stabilized and / or recovered 49 and 52 of the unstablelipids, respectively, to a fraction of 0.90 or better. Quercetin alone and quercetin + BHT + phloroglucinol stabilized and / or recovered 29 and 33 of the unstable lipids, respectively, to a fraction of 0.90 or better. Together, the full set of screened preservatives yielded stabilization and / or recovery of 73 of those 159 unstable lipids to a fraction of 0.90 or better.

[0120] Interestingly, the lipid data indicate that the preservative SSA is overall highly effective, but SSA appears to significantly degrade or decrease recovery of specific lipid subclasses including acylcamitines (CAR species), cholesterol and cholesterol esters, cardiolipins, phosphatidic acids, and triglycerides.

[0121] Example 3. Unstable cellular metabolome and methods for stabilizing it

[0122] Methods

[0123] Cell culture

[0124] MCF-7 cells were cultured in a T-225 cm2flask containing RPMI 1640 medium (Hyclone Laboratories) supplemented with 5% fetal bovine serum and 2 mM L-glutamine. Cells were maintained at 37°C in a humidified atmosphere and 5% CO2. Upon reaching 70% confluence, cells were washed with 10 mL phosphate buffered saline and harvested by adding 2 mL trypsin, incubating for 5 min, and neutralizing with 6 mL fresh medium. The cell suspension was transferred to a 50 mL centrifuge tube and centrifuged at 500 g for 2 min. After centrifugation, the supernatant was aspirated, and the cells were resuspended with 6 mL fresh medium. Cells were counted and aliquoted into 1.5 mL microcentrifuge tubes containing three million cells each and centrifuged again at 500 g for 2 min. After centrifugation, supernatant was aspirated, and the cell pellet was kept at -80°C until extraction.

[0125] Metabolite extraction and preservation

[0126] The extraction solvent used for the no-preservative control condition was methanol: water = 80:20 containing 0.1% ammonium hydroxide and 2 pM13C3-lactate as a recovery standard. The following preservatives were added: quercetin (Q), phloroglucinol (P), butylated hydroxytoluene (B), a-cyclodextrin (A), sodium ascorbate (vitamin C, V), deferoxamine (D), and sulfosalicylic acid (S).

[0127] Metabolite Extraction and Preservation

[0128] Cell pellets were extracted using 200 pL ice-cold extraction solvent, vortexed for 2 min, and centrifuged at 17,000 g, 4°C, for 10 min. Supernatant was transferred to an autosampler vial and injected into the IC-MS immediately (±3 min) for representation of the zero-time point (t=0). Additional timepoints were injected.

[0129] Instrument method

[0130] IC mobile phase A (MPA, weak) was water, and mobile phase B (MPB, strong) was water containing 100 mM KOH. A Thermo Scientific Dionex ICS-6000+ system included a Thermo lonPac ASH column (4 pm particle size, 250 x 2 mm) with column compartment kept at 20°C. The autosampler tray was chilled to 10°C. The mobile phase flow rate was 360 pL / min, and the gradient elution program was: 0-6 min, 1% MPB; 6-13 min, 1-15% MPB; 13-19.5 min, 15-30% MPB; 19.5-27 min, 30-85% MPB; 27-29 min, 85% MPB; 29 min, 85-1% MPB. The total run time was 35 min. To increase desolvation for better sensitivity, 2 mM acetic acid in methanol was delivered by an external pump at a flow rate of 50 pL / min and combined with the eluent via a low dead volume mixing tee.

[0131] Ultra-high resolution mass spectrometry

[0132] A Thermo Orbitrap IQ-X Tribrid Mass Spectrometer was operated in full scan mode using a scan range of 70-800 m / z and a resolution of 240,000. ESI negative ionization mode included a spray voltage of -2,800 (V) and vaporizer and capillary temperatures of 350°C and 300°C, respectively. The sheath, auxiliary, and sweep gas pressures were 40, 15, and 1 (arbitrary units), respectively.

[0133] Data Analysis

[0134] Raw mass spectra were acquired using Thermo XCaliber, and the resulting *.raw files were imported into Skyline Software for peak picking, chromatogram alignment, annotation, and peak integration. GraphPad Prism 10 was used to plot time course data, generate multivariable analyses, and calculate AUC values.

[0135] Results

[0136] A large fraction of the cellular metabolome is unstable

[0137] To characterize the stable and unstable subsets of the cellular metabolome, the MCF7 breast cancer cell line was used, because cultured cells present a rich source of metabolites and enable the time frame between sample collection and analysis to be decreased to only minutes. Ion chromatography-mass spectrometry (IC-MS) was used because this analytical method is effective at resolving polar, isobaric energy metabolites that are challenging to resolve using routine liquid chromatography (LC)-MS. Metabolites were from cultured MCF7 cells and iterative IC-MS analysis was performed by re-injecting the extract at time points 0, 5, 10, 15, 20, 25, and 3600 h (5 months), which yielded 130 annotated metabolites including amino acids (FIGs. 3A-3G), fatty acids (FIGs. 4A-4B), vitamins (FIG. 10), metabolites involved in glycolysis (FIGs. 5A-5E), nucleotide metabolism (FIGs. 6A-6M), the TCA cycle (tricarboxylic acid cycle, citric acid cycle, or the Krebs cycle, FIGs. 9A-9C), pentose phosphate pathway (PPP, FIGs. 8A-8D), and other metabolic pathways (FIGs. 7A-7E). Using Equation la (stability =100 * (max-min) / max) and a 30% signal loss threshold to define stability, 16% (21 / 130) of metabolites without a preservative exhibited 5-month stability; 15% (20 / 130) were stable for 25 h then degraded by 5 months in storage at -80°C; and 68% (89 / 130) were classified as highly unstable due to degradation within 25 h (see Table 7 below). Stability was also calculated using Equation lb: [100*t(fmai) / (t(0)]. These findings underscore the great extent of stability challenges in metabolomics.

[0138] The unstable cellular metabolome can be stabilized

[0139] Candidate preservatives were compiled, including quercetin (Q), butylated hydroxytoluene (B), phloroglucinol (P), a-cylcodextrin (A), vitamin C (V), deferoxamine (D), and sulfosalicylic acid (S). Preservatives were integrated into the aforementioned workflow by spiking various preservative combinations into the extraction solvent. Of the 89 highly unstable metabolites that degraded within 25 h without preservative, 79 were stabilized for 25 h by at least one preservative condition, and 61 were stabilized for 5 months (see Table 7 below). Of the 20 metabolites that degraded between 25 h and 5 months, 80% (16 / 20) were stabilized for 5 months by at least one preservative condition. QBPVD, SQBP, SQBPAV, and SQBPVD were the most effective preservative combinations for extending stability from less than 25 h to 25 h, and QB, QBP, and QBPAV were the most effective preservative combinations for extending stability to 5 months. Although deferoxamine and sulfosalicylic acid were effective for 25-h stabilization,they were ultimately deleterious to most metabolites. These results suggest that the unstable cellular metabolome can be effectively stabilized by preservatives.

[0140] Preservatives for metabolite signal enhancement

[0141] While analyzing metabolite stability data, it was observed that some preservatives produced notable signal enhancement. To quantitatively assess preservative-mediated signal enhancement relative to the no-preservative (NP) control, the area under the curve (AUC) was calculated for each time series and signal enhancement was determined using Equation 2 ( 100 X [AUCpreservative-AUCNo Preservative] / AUCNo Preservative). Because AUC represents total metabolite signal integrated over time, in addition to adding resilience to outliers, it also detects signal enhancement that may arise from mechanisms other than stabilization, such as increased ionization efficiency and / or decreased ion suppression due to mitigation of matrix effects. After filtering out metabolites for which signal was enhanced but not stable, it was found that 68 metabolites exhibited both 25-h stability and signal enhancement, of which 40 exhibited 5 -month stability and signal enhancement (FIGs. 3-10). QBP was the most effective preservative for metabolite signal enhancement, yielding the majority of the aforementioned 68 and 40 enhancements, respectively.

[0142] The potent preservation effects of QBP can be most clearly seen with glutamylglutamate (Glu-Glu), orotidine, CDP, and 3 -hydroxybutyrate, which exhibited up to 249% signal enhancement. Notable signal enhancement with other preservatives included: 1,100% for phosphocreatine (QBPAV), 1,100% for glucarate (QBP AV), 5,600% for hydroxypropanedioate (SQBPAV), 1,900% for maleate (SQBPAV), 8,300% for oxalate (SQBPAV), 2,100% for threonate (QBPAV), and 1,100% for 2-oxoglutarate (a-KG) (SQBPAV). Although sulfosalicylic acid-containing preservative combinations mediated a number of those striking signal enhancements, sulfosalicylic acid-containing preservatives yielded decreased signals for most metabolites.

[0143] To validate our findings, additional triplicate analyses of the no-preservative, QBPAV, SQBP, and SQBPAV conditions were performed.

[0144] Table 7 provides a summary of all 130 metabolites, their stability without preservatives, the optimal choice of preservative for each metabolite, and the degree of stability achieved with the recommended preservative. The number of metabolites that exhibited optimal stability and signal with each preservative condition was: 7 no-preservative, 3 QB, 55 QBP, 36 QBPAV, 9 QBPVD, 0 SQB, 16 SQBP, 21 SQBPAV, and 4 SQBPVD. Some metabolites yielded comparable results with more than one condition; for example, ribonate exhibited similar stability and signal with SQBP and SQBPAV, so Table 7 lists both of those preservatives as options for improving the measurement of ribonate. Overall, 92% (121 / 130) of metabolites exhibited improved stability or combined stability and signal enhancement using a preservative. Of the 10 metabolites that did not, five (2- phosphogly cerate, 3 -phosphoglycerate, phosphoenol pyruvate, dATP, and FAD) performed best with no preservative, and five (cAMP, FMN, maleate, deoxyribose 5-phosphate, and ribose 1,5 -bisphosphate) were non-stabilizable under the conditions tested.Table 7. Stability of metabolites from MCF7 cells in the presence and absence of a preservative.

[0145] Example 4. Unstable urine metabolites and methods for stabilizing urine metabolites

[0146] Methods

[0147] A fresh urine sample (target 20+ mL) was collected from healthy volunteers in 50 mL tube, and 10 mL was immediately transferred to a 50 mL tube containing 100 pL methanol: water = 80:20 (no-preservative) and a separate 10 mL aliquot to a 50 mL tube containing 100 pL methanol: water = 80:20 containing preservative. The tube was inverted lOx to mix the preservative. A 0.22 pm microcentrifuge filter tube was conditioned by adding water, centrifuged at 800 g and 4°C for 5 min, and the water filtrate was disposed. 500 pL urine sample was transferred onto the filter and centrifuged at 800 g and 4°C for 5 min. 30 pL filtered urine was aliquoted onto an osmometer and osmolarity was measured. All samples were diluted by adding deionized (18.2 MQ cm) water to filtered urine samples; osmolarity was adjusted to 20 mmol / kg. 200 pL diluted urine was transferred to a clean injection vial, 10 pL isotopically labeled internal standard mixture was added and vortexed briefly. 5 pL was injected directly on IC-MS for t=0. Sample was injected every 5 h. To facilitate accurate comparison of metabolite stability across preservative conditions (and subjects), values were normalized by dividing all measured values (AUCs) by the corresponding t=0 value.

[0148] Results

[0149] Urine metabolites were tested for their stability in the presence and absence of a collection of preservatives. A collection of candidate preservatives were compiled, including quercetin (Q), butylated hydroxytoluene (B), phloroglucinol (P), a-cylcodextrin (A), vitamin C (V), deferoxamine (D), sulfosalicylic acid (S), diethylenetriaminepentaacetic acid (DTP A), and catechin hydrate (C). A summary of the stability test is shown in Tables 8A-8D.

[0150] It was found that 100% of the urine metabolites were unstable without a preservative (Table 8A and 8C), and QBPVD was the most effective preservative for urine metabolites, rescuing most of the unstable metabolites to 25-hour stability (Table 8A and 8C).

[0151] It was also found that some preservatives produced notable signal enhancement(Table 8E and 8F)Table 8A. Stability of metabolites in urine in the presence of QBP, QBPAV, QBPVD, QBP&DTPA, and QBPVD&DTPA and absence (NP) of a preservative.Table 8B. Stability of metabolites in urine in the presence of SQBP, SQBPAV, CQBP,CQBPAV, SQBP&DTPA, and SQBPAV&DTPA.Table 8C. Stability of metabolites in urine in the presence of QBP, QBPAV, QBPVD,QBP&DTPA, and QBPVD&DTPA and absence (NP) of a preservative.Table 8D. Stability of metabolites in urine in the presence of SQBP, SQBPAV, CQBP, CQBPAV, SQBP&DTPA, and SQBPAV&DTPA.Table 8E. Enhancement of the signal of metabolites in urine in the presence of QBP, QBPAV, QBPVD, QBP&DTPA, and QBPVD&DTPA.Table 8F. Enhancement of the signal of metabolites in urine in the presence of SQBP, SQBPAV, CQBP, CQBPAV, SQBP&DTPA, and SQBPAV&DTPA.

[0152] Example 5. Unstable whole blood metabolites and methods for stabilizing whole blood metabolites

[0153] Methods

[0154] A fresh blood sample (target 500 pL) was collected from a healthy volunteer into a preservative-free tube, and 20 pL was immediately transferred to a tube containing 80 pLdry ice-cold (-20°C) methanol (without preservative), and a separate 20 pL aliquot was transferred to a tube containing 80 pL dry ice-cold (-20°C) methanol and the indicated preservative. 50 pL ice-cold (4°C) water and 100 pL ice-cold chloroform were added to the sample. The sample was placed in a multi-tube vortexer for 2 min at 4°C, then centrifuged at 16,100 g and 4°C for 5 min. The upper (methanol -water) fraction was collected and analyzed as described previously.

[0155] Results

[0156] Whole blood metabolites were tested for their stability in the presence and absence of a collection of preservatives. A collection of candidate preservatives were compiled, including quercetin (Q), butylated hydroxytoluene (B), phloroglucinol (P), a-cylcodextrin (A), vitamin C (V), deferoxamine (D), sulfosalicylic acid (S), diethylenetriaminepentaacetic acid (DTP A), and catechin hydrate (C). A summary of the stability test is shown in Tables 9A-9B.

[0157] It was found that QBP was the most effective preservative for whole blood metabolites, rescuing most of the unstable metabolites to 25-hour stability, and the addition of DTP A further improved the stability of a number of metabolites (Table 9A and 9B).

[0158] It was also found that some preservatives produced notable signal enhancement (Table 9C)Table 9A. Stability of metabolites in whole blood in the presence of QBP, QBP AV, QBPVD, SQBP, SQBPAV, and SQBPVD and absence (NP) of a preservative.Table 9B. Stability of metabolites in whole blood in the presence of NP, QBP, QBP& DTP A, QBP AV, QBPAV&DTPA, QBPVD, QBPV&DTPA, SQBP, SQBPAV, SQBPVD and absence (NP) of a preservative.Table 9C. Enhancement of the signal of metabolites in whole blood in the presence of QBP, QBPAV, QBPVD, QBP&DTPA, QBPVD&DTPA, SQBP, SQBPAV, and SQBPVD.

[0159] The embodiments, illustratively described herein may suitably be practiced in the absence of any element or elements, limitation or limitations, not specifically disclosed herein. Thus, for example, the terms “comprising,” “including,” “containing,” etc. shall be read expansively and without limitation. Additionally, the terms and expressions employed herein have been used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the claimed technology. Additionally, the phrase “consisting essentially of’ will be understood to include those elements specifically recited and those additional elements that do not materially affect the basic and novel characteristics of the claimed technology. The phrase “consisting of’ excludes any element not specified.

[0160] The present disclosure is not to be limited in terms of the particular embodiments described in this application. Many modifications and variations can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. Functionally equivalent methods and compositions within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from theforegoing descriptions. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that this disclosure is not limited to particular methods, reagents, compounds, or compositions, which can of course vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

[0161] In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

[0162] As will be understood by one skilled in the art, for any and all purposes, particularly in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein can be readily broken down into a lower third, middle third and upper third, etc. As will also be understood by one skilled in the art all language such as “up to,” “at least,” “greater than,” “less than,” and the like, include the number recited and refer to ranges which can be subsequently broken down into subranges as discussed above. Finally, as will be understood by one skilled in the art, a range comprises each individual member.

[0163] All publications, patent applications, issued patents, and other documents referred to in this specification are herein incorporated by reference as if each individual publication, patent application, issued patent, or other document was specifically and individually indicated to be incorporated by reference in its entirety. Definitions that are contained in text incorporated by reference are excluded to the extent that they contradict definitions in this disclosure.I l l

Claims

WHAT IS CLAIMED IS1. A system, comprising: a sample collection device; and a preservative system comprising a preservative, wherein the preservative is selected from the group consisting of an antioxidant, a chelator, an inert gas, an inert host structure, a kosmotrope, a protein precipitator, and a combination of two or more thereof.

2. The system of claim 1, wherein the preservative is selected from the group consisting of: 3,4-dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N-Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin C (ascorbic acid), Vitamin E (tocopherol), tris(2- carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alphacyclodextrin, beta-cyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, 5-sulfosalicylic acid (SSA), trifluoroethanol (TFE), trichloroacetic acid (TCA), and a combination of two or more thereof.

3. The system of claim 1 or claim 2, wherein the preservative system comprises 5- sulfosalicylic acid and at least one preservative selected from the group consisting of 3,4- dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N-Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin C (ascorbic acid), Vitamin E (tocopherol), tris(2-carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alpha-cyclodextrin, beta- cyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, trifluoroethanol (TFE), and trichloroacetic acid (TCA).

4. The system of claim 1 or claim 2, wherein the preservative system comprises quercetin, phloroglucinol, and BHT.

5. The system of claim 1 or claim 2, wherein the preservative system comprises quercetin and phloroglucinol.

6. The system of claim 1 or claim 2, wherein the preservative system comprises BHT and phloroglucinol.

7. The system of claim 1 or claim 2, wherein the preservative system comprises quercetin and catechin.

8. The system of claim 1 or claim 2, wherein the preservative system comprises ascorbic acid and at least one preservative selected from the group consisting of 3,4- dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N-Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin E (tocopherol), tris(2-carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alpha-cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, 5-sulfosalicylic acid (SSA), trifluoroethanol (TFE), and trichloroacetic acid (TCA).

9. The system of claim 1 or claim 2, wherein the preservative system comprises ascorbic acid and a-cyclodextrin.

10. The system of claim 1 or claim 2, wherein the preservative system comprises ascorbic acid and butylated hydroxy toluene.

11. The system of claim 1 or claim 2, wherein the preservative system comprises ascorbic acid and deferoxamine.

12. The system of claim 1 or claim 2, wherein the preservative system comprises ascorbic acid and phloroglucinol.

13. The system of claim 1 or claim 2, wherein the preservative system comprises caffeic acid.

14. The system of claim 1 or claim 2, wherein the preservative system comprises phloroglucinol.

15. The system of claim 1 or claim 2, wherein the preservative system comprises catechin.

16. The system of claim 1 or claim 2, wherein the preservative system comprises quercetin.

17. The system of claim 1 or claim 2, wherein the preservative system comprises chi orogenic acid.

18. The system of claim 1 or claim 2, wherein the preservative system comprises EDTA.

19. The system of claim 1 or claim 2, wherein the preservative system comprisesEGCG.

20. The system of claim 1 or claim 2, wherein the preservative system comprises BHA.

21. The system of claim 1 or claim 2, wherein the preservative system comprises TCA.

22. The system of claim 1 or claim 2, wherein the preservative system comprises BHT.

23. A method of collecting a biological analyte, the method comprising: delivering a preservative system into a sample collection device; delivering a biological sample to the sample collection device; processing the biological sample to obtain a solution containing the biological analyte; and collecting the biological analyte; wherein the preservative system stabilizes the biological analyte for analysis.

24. The method of claim 23, wherein the biological analyte is selected from the group consisting of a metabolite, a lipid, a nucleic acid, and a protein.

25. The method of claim 23 or claim 24, wherein the method improves recovery of the biological analyte compared to a method that does not comprise the preservative system.

26. The method of any one of claims 23-25, wherein the biological sample selected from the group consisting of blood, plasma, serum, tissues, cells, media, urine, stool, and saliva.

27. The method of any one of claims 23-26, wherein the preservative system comprises a preservative selected from the group consisting of 3,4-dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N-Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin C (ascorbic acid), Vitamin E (tocopherol), tris(2-carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alpha-cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, 5-sulfosalicylic acid (SSA), trifluoroethanol (TFE), trichloroacetic acid (TCA), and a combination of two or more thereof.

28. The method of any one of claims 23-27, wherein the preservative system comprises ascorbic acid and a-cyclodextrin; and the biological analyte is selected from the group consisting of 2-hydroxyglutarate, acetylcarnitine, adenyl succinic acid, arabinonic acid, ATP, dATP, beta-citryl-glutamate, citric acid, CTP, galactaric acid, glucaric acid, gluconic acid, glycerol 3 -phosphate, dGTP, homocysteinesulfmic acid, hydroxypropanedioc acid, ketoleucine, lactic acid, mesaconic acid, oxalic acid, phosphoadenosine phosphosulfate, pyruvic acid, sulfate, TTP, UTP, and a combination of two or more thereof.

29. The method of any one of claims 23-27, wherein the preservative system comprises ascorbic acid and butylated hydroxy toluene; and the biological analyte is selected from the group consisting of 2-hydroxyglutarate, acetylcarnitine, adenyl succinic acid, arabinonic acid, ATP, dATP, beta-citryl-glutamate, citric acid, galactaric acid, glucaric acid, gluconic acid, glycerol 3 -phosphate, dGTP, hydroxypropanedioc acid, lactic acid, mesaconic acid, oxalic acid, phosphoadenosine phosphosulfate, pyruvic acid, TTP, and a combination of two or more thereof.

30. The method of any one of claims 23-27, wherein the preservative system comprises ascorbic acid and deferoxamine; and the biological analyte is selected from the group consisting of adenylsuccinic acid, arabinonic acid, ATP, dATP, beta-citryl-glutamate, citric acid, CTP, dCTP, galactaric acid, glucaric acid, gluconic acid, GTP, dGTP, homocysteinesulfmic acid, hydroxypropanediocacid, lactic acid, mesaconic acid, oxalic acid, phosphoadenosine phosphosulfate, sulfate, TTP, uric acid, UTP, and a combination of two or more thereof.

31. The method of any one of claims 23-27, wherein the preservative system comprises ascorbic acid and phloroglucinol; and the biological analyte is selected from the group consisting of 2-hydroxyglutarate, acetylcarnitine, adenyl succinic acid, arabinonic acid, ATP, dATP, beta-citryl-glutamate, citric acid, galactaric acid, glucaric acid, gluconic acid, dGTP, hydroxypropanedioc acid, lactic acid, mesaconic acid, oxalic acid, phosphoadenosine phosphosulfate, pyruvic acid, TTP, and a combination of two or more thereof.

32. The method of any one of claims 23-27, wherein the preservative system comprises quercetin and phloroglucinol; and the biological analyte is selected from the group consisting of 2-aminomuconic acid semialdehyde, 5'-phosphoribosyl-N-formylglycinamide, 6-phosphogluconic acid, acetylcamitine, AICAR, cis aconitic acid, dehydroascorbic acid, fumarate, glucose 6- phosphate, erythrose 4-phosphate, glycerol 3 phosphate, itaconate, orotidine, and a combination of two or more thereof.

33. The method of any one of claims 23-27, wherein the preservative system comprises quercetin, phloroglucinol, and butylated hydroxy toluene.

34. The method of claim 33, wherein the preservative system further comprises DTPA.

35. The method of any one of claims 23-27, wherein the preservative system comprises caffeic acid, and the biological analyte comprises acetyl CoA, malonyl CoA, succinyl CoA, or a combination of two or more thereof.

36. The method of any one of claims 23-27, wherein the preservative system comprises phloroglucinol, and the biological analyte comprises acetyl CoA, malonyl CoA, or a combination thereof.

37. The method of any one of claims 23-27, wherein the preservative system comprises SSA, andthe biological analyte comprises succinyl CoA.

38. The method of any one of claims 23-27, wherein the preservative system comprises caffeic acid, and the biological analyte comprises putrescine, spermidine, spermine, or a combination of two or more thereof.

39. The method of any one of claims 23-27, wherein the preservative system comprises chi orogenic acid, and the biological analyte comprises ornithine, spermidine, spermine, or a combination of two or more thereof.

40. The method of any one of claims 23-39, wherein the biological analyte is analyzed using ion chromatography-mass spectrometry (IC-MS).

41. A preservative system for improving recovery and / or stability of a biological analyte, the preservative system comprising: a preservative selected from the group consisting of an antioxidant, a chelator, an inert gas, an inert host structure, a kosmotrope, and a protein precipitator, and a combination of two or more thereof.

42. The preservative system of claim 41, wherein the preservative comprises the 3,4- dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N-Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin C (ascorbic acid), Vitamin E (tocopherol), tris(2-carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alpha-cyclodextrin, betacyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, 5-sulfosalicylic acid (SSA), trifluoroethanol (TFE), trichloroacetic acid (TCA), and a combination of two or more thereof.

43. The preservative system of claim 41 or 42, wherein the preservative comprises 5- sulfosalicylic acid and at least one preservative selected from the group consisting of 3,4- dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA),butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N-Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin C (ascorbic acid), Vitamin E (tocopherol), tris(2-carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alpha-cyclodextrin, betacyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, trifluoroethanol (TFE), and trichloroacetic acid (TCA).

44. The preservative system of claim 41 or 42, wherein the preservative comprises ascorbic acid and at least one preservative selected from the group consisting of 3,4- dihydroxyphenyl acetic acid, andrographolide, apigenin, butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), caffeic acid, caffeic acid phenethyl ester (CAPE), carvacrol, catechin, chlorogenic acid, epigallocatechin gallate (EGCG), ethoxyquin, ferrulic acid, N-Acetylcysteine (NAC), phloroglucinol, procyanidin, quercetin, thiamine, trolox, Vitamin E (tocopherol), tris(2-carboxyethyl)phosphine hydrochloride (TCEP), deferoxamine, ethylene diamine tetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTP A), argon, nitrogen, alpha-cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin, mannitol, sorbitol, glycerol, isomalt, 5-sulfosalicylic acid (SSA), trifluoroethanol (TFE), and trichloroacetic acid (TCA).

45. The preservative system of claim 41 or 42, wherein the preservative comprises ascorbic acid and a-cyclodextrin.

46. The preservative system of claim 41 or 42, wherein the preservative comprises ascorbic acid and butylated hydroxy toluene.

47. The preservative system of claim 41 or 42, wherein the preservative comprises ascorbic acid and deferoxamine.

48. The preservative system of claim 41 or 42, wherein the preservative comprises ascorbic acid and phloroglucinol.

49. The preservative system of claim 41 or 42, wherein the preservative comprises quercetin and catechin.

50. The preservative system of claim 41 or 42, wherein the preservative comprises quercetin and phloroglucinol.

51. The preservative system of claim 41 or 42, wherein the preservative comprises BHT and phloroglucinol.

52. The preservative system of claim 39 or 40, wherein the preservative comprises quercetin, phloroglucinol, and BHT.

53. The preservative system of claim 52, wherein the preservative further comprises DTPA54. The preservative system of claim 41 or 42, wherein the preservative comprises caffeic acid.

55. The preservative system of claim 41 or 42, wherein the preservative comprises phloroglucinol.

56. The preservative system of claim 41 or 42, wherein the preservative comprises catechin.

57. The preservative system of claim 41 or 42, wherein the preservative comprises quercetin.

58. The preservative system of claim 41 or 42, wherein the preservative comprises chi orogenic acid.

59. The preservative system of claim 41 or 42, wherein the preservative comprises EDTA.

60. The preservative system of claim 41 or 42, wherein the preservative comprises EGCG.

61. The preservative system of claim 41 or 42, wherein the preservative comprises BHA.

62. The preservative system of claim 41 or 42, wherein the preservative comprises TCA.

63. The preservative system of claim 41 or 42, wherein the preservative comprises BHT.

64. The preservative system of claim 41 or 42, wherein the preservative comprises SSA, BHT, quercetin, phloroglucinol, or a combination of two or more thereof, and the biological analyte comprises a lipid.

65. The preservative system of claim 41 or 42, wherein the preservative is selected based on at least one of a characteristic or class of the biological analyte or a target analysis process for which the biological analyte is to be preserved.

66. The system of any one of claims 1-22, wherein the sample collection device comprises a dry blood spot collection device, a urine collection device, a stool collection device, or a blood collection device.

67. A method of collecting a biological analyte from a cell, the method comprising: delivering a preservative system into a sample collection device; delivering the cell to the sample collection device; processing the cell to obtain a solution containing the biological analyte; and collecting the biological analyte; wherein the preservative system stabilizes the biological analyte for analysis.

68. The method of claim 67, wherein the biological analyte is selected from the group consisting of a metabolite, a lipid, a nucleic acid, and a protein.

69. The method of claim 67 or 68, wherein the biological analyte is selected from the group consisting of 2-aminomuconate, 2-methylglutarate, 3-hydroxymethylglutarate, 4- hydroxyglutamate semialdehyde, acetylcarnitine, citryl-glutamate, cysteate, gammaglutamylalanine (g-Glu-Ala), gamma-glutamyltaurine, glutamylglutamate (Glu-Glu), glutathione, reduced (GSH), homocysteinesulfmate, ketoleucine, N-acetylaspartate, N- acetylglutamate, N-acetylmethionine, N-acetylneuraminate, N-formylmethionine, orotate, orotidine, pantothenate, phosphocreatine, phosphoserine (p-Ser), pyroglutamate (pGlu), taurine, ureidosuccinate, 2-hydroxybutyrate, 3 -hydroxybutyrate, butyrate, glycerylphosphorylethanolamine, O-phosphoethanolamine, 2,3 -diphosphoglycerate, 2- phosphogly cerate, fructose 1,6-bisphosphate, fructose 1 -phosphate, fructose 2,6- bisphosphate, fructose 6-phosphate, glucose, glucose 1 -phosphate, glucose 6-phosphate, glycerol 3 -phosphate, lactate, mannose 1 -phosphate, mannose 6-phosphate, phosphoenolpyruvate, pyruvate, 2'-deoxyadenosine 5'-diphosphate (dADP), 2'-deoxyadenosine 5'-triphosphate (dATP), 2'-deoxycytidine 5'-diphosphate (dCDP), 2'- deoxycytidine 5'-triphosphate (dCTP), 2'-deoxyguanosine 5'-diphosphate (dGDP), 2'- deoxyguanosine 5'-monophosphate (dGMP), 2'-deoxyguanosine 5'-triphosphate (dGTP), 2'- deoxyuridine 5' monophosphate (dUMP), 3 '-deoxythymidine 5'-diphosphate (dTDP), 3'- deoxythymidine 5'-triphosphate (dTTP), adenosine 3'-phosphate 5'-phosphosulfate, adenosine 5 '-diphosphate (ADP), adenosine 5'-monophosphate (AMP), adenosine 5'- triphosphate (ATP), adenyl succinate, ADP -glucose, ADP-ribose, ADP-ribose 2'-phosphate, CDP-ethanolamine, CMP-N-acetylneuraminate, cyclic AMP (cAMP), cytidine 5' monophosphate (CMP), cytidine 5'-diphosphate (CDP), cytidine 5'-triphosphate (CTP), flavin adenine dinucleotide (FAD), flavin mononucleotide (FMN), GDP-mannose, guanosine 5'-diphosphate (GDP), guanosine 5'-monophosphate (GMP), guanosine 5'- triphosphate (GTP), inosine 5'-monophosphate (IMP) / inosinate, nicotinamide adenine dinucleotide, reduced (NADH), pyridoxal 5'-phosphate (P5P), thymidine 5'-diphosphate (TDP), thymidine 5'-monophosphate (TMP), thymidine 5'-triphosphate (TTP), UDP- galactose, UDP -glucose, UDP-N-acetylgalactosamine (UDP-GalNAc), UDP-N- acetylglucosamine (UDP-GlcNAc), urate, uridine, uridine 5'-diphosphate (UDP), uridine 5'- monophosphate (UMP), uridine 5'-triphosphate (UTP), xansthosine 5'-monophosphate (XMP) / xanthylic acid, l-pyrroline-2-carboxylate, 2-hydroxyadipate, 5'-phosphoribosyl-N- formylglycinamide, galactarate, galactose 1 -phosphate, glucarate, glutarate, glycerate, hydroxypropanedioate, maleate, malonate, oxalate, ribonate, threonate, deoxyribose 5- phosphate, erythrose 4-phosphate, gluconate, gluconate 6-phosphate, glucono- 1,5 -lactone, glucono- 1,5 -lactone 6-phosphate, phosphoribosyl pyrophosphate (PRPP), ribose 1,5- bisphosphate, ribose 1 -phosphate, sedoheptulose 1,7-bisphosphate, sedoheptulose 7- phosphate, 2-hydroxy glutarate (2-HG), 2-oxoglutarate (a-KG), aspartate (Asp), cisaconitate, citrate, fumarate, glutamate (Glu), isocitrate, malate, oxaloacetate (OAA), succinate, succinate semialdehyde, and riboflavin cyclic-4', 5'-phosphate.

70. The method of any one of claims 67-69, wherein the preservative system comprises quercetin, BHT, phloroglucinol, alpha-cyclodextrin, Vitamin C, deferoxamine, SSA, or a combination of any two or more thereof.

71. The method of any one of claims 67-70, wherein the preservative system comprises quercetin, BHT, and phloroglucinol.

72. A method of collecting a biological analyte from urine, the method comprising:delivering a preservative system into a sample collection device; delivering the urine to the sample collection device; processing the urine to obtain a solution containing the biological analyte; and collecting the biological analyte; wherein the preservative system stabilizes the biological analyte for analysis.

73. The method of claim 72, wherein the biological analyte is selected from the group consisting of a metabolite, a lipid, a nucleic acid, and a protein.

74. The method of claim 72 or 73, wherein the biological analyte is selected from the group consisting of 2-Aminoadipic acid, 2-Keto-glutaramic acid, 2-methylcitric acid, 2- Methylglutaric acid, 2-Methylhippuric acid, 2-Pyrrolidone, 2-ureidoglycine, 4-Hydroxy-D- proline, 6-Oxo-pipecolinic acid, Acetylasparagine, Acetylornithine, acetyltaurine, Allantoin, alpha-Aspartyl-4-hydroxyproline, Aminolevulinic acid, asn-val, Aspartic acid, Aspartylaspartic acid, Azelaic acid, CYS-ASP, Cysteine-S-sulfate, Formylisoglutamine, Formylkynurenine, gamma-glutamyltyramine, g-Glutamylcysteine, Glutamate, Glutamine, Glutaurine, Gly-His, Gly-thr, Hippuric acid, Histidine, Histidinol, Homocysteic acid, Hydroxyglutaric acid, Isoleucyl-4-hydroxyproline, Isovalerylglycine, Levulinic acid, Methionine, N-(lH-Pyrrol-2-ylcarbonyl)glycine, N-(2-Sulfoethyl)alanine, N-(3,4- Dihydroxyphenyl)glutamine, N-Acetylalanine, N-Acetylalloisoleucine, N-Acetylaspartic acid, N-AcetylCitrulline, N-Acetylcysteine, N-Acetylglutamic acid, N-Acetylglutamine, N- Acetylglycine, N-Acetylvaline, N-Formylaspartate, N-Isovalerylglycine, N- Phenylacetylglutamine, N-Propionylmethionine, N-Tigloylglycine, Phenylacetylglycine, Picolinic acid, pyroglutamine, pyroglutamylglycine, Succinyl proline, Taurine, Threonic acid, thr-pro, Thymine, tyramine sulfate, 2,3-Dihydroxypropanoic acid, 2-Butynedioic acid, 2-Oxo-4-pentenoic acid, 3 -Hydroxybutyric acid, 3 -Methylbutanoic acid, 4,5- Dideoxypentonic acid, 4-Hydroxy-2-methylbenzoic acid, 4-Hydroxyphenylacetylglycine, Arachidonic acid, Biacetyl, Capryloylglycine, Cinnamoylglycine, Diacetyl, Ethyl acetate, Ethylmalonic acid, Gamma-Hydroxybutyric acid, Glucoheptonic Acid, Linoleic Acid, Maleamic acid, Maleic acid, Malondialdehyde, Malonic acid, Mevalonic acid, Nitropropionic acid, 2-deoxy glucose, 3 -Ketosucrose, alpha-Methyl D-mannoside, ascorbate 6-phosphate, Ascorbic acid 2-sulfate, Galactonic acid, galactosyl-L-rhamnose, glyceraldehyde 3 -phosphate, glycerin, Glycolic acid, homoserine lactone, Lactic Acid, Mannitol, Mannopyranose, N-glycoloyl-D-mannosaminolactone, Saccharic acid, S-methylD-thioglycerate, Sucrose, Adenine, cAMP, deoxyuridine, Dihydrothymine, Dihydrouridine, methylxanthine, myo-Inositol 1,4-bisphosphate, Orotidine, Oxalic acid, Pseudouridine, Uracil, Uric acid, Xanthine, 6-Deoxy-3-O-methyl-beta-D-galactopyranose, 6-O-Sulfo- alpha-D-galactopyranose, Butyryl-L-homoserine lactone, Dihyroxy-lH-indole glucuronide I, N-Acetylgalactosamine 4-sulfate, N-Acetylglucosaminitol, N-Acetylneuraminic acid, Glucopyranuronic acid, Arabic acid, Arabitol, Erythritol, Erythrose, Galacturonic acid, Gluconic acid, Glucono-delta-lactone, glucosone, Glutaconic acid, Xylitol, Ribono-1,4- lactone, Aconitic Acid, Citraconic acid, Citric acid, hydroxycitric acid, Itaconic acid, Pyruvic acid, Succinic acid, Succinic semialdehyde, trans-Aconitic acid, Pantothenic acid, 1,2-Dimethylhydrazine, 2-Anisic acid, 2-Hydroxyhippuric acid, 3-(5-oxoisoxazolin-2-yl)-L- alanine, 3,5-Dihydroxyphenylglycine, 3 -amino- 1 -phenylurea, 3 -Hydroxy-3 -methylglutaric acid, 3-Hydroxyanthranilic acid, 3-Methylhippuric acid, 3-Ribofuranosyluric acid, 3- Sulfamoylalanine, 4- Aminophenol, 4-Aminopyridine, 4-Hydroxy-3- methoxyphenylglycol sulfate, 4-methylthioanisole, 4-Nitroaniline, 4-Oxoproline, 5 -Formyluracil, 5- Heptenoylglycine, 5-Hydroxyindole-3-acetic acid, 5-hydroxyisouric acid, 5-Indolol, 6,7- Dihydropteridine, 6-Aminopyrimidine-2,4,5-triol, 9-Methyluric acid, Allopyranose, clavulanic acid, ethenocytosine, Hept-2-ulose, Isethionic acid, Mesaconic acid, methyl thioacetate, Muconic acid, N-furfurylformamide, Oxalylurea, p-Cresol, Phosphoric acid, Pyrogallol, Pyrogallol-2-O-sulphate, Pyrophosphoric Acid, Quinic acid, Quinolinic acid, Salicyluric acid, Theophylline, Valyl-4-hydroxyproline, Vanillyl mandelic acid, and Xylopyranose.

75. The method of any one of claims 72-74, wherein the preservative system comprises quercetin, BHT, phloroglucinol, alpha-cyclodextrin, Vitamin C, deferoxamine, SSA, DTP A, catechin, or a combination of any two or more thereof.

76. The method of any one of claims 72-75, wherein the preservative system comprises quercetin, BHT, phloroglucinol, Vitamin C, and deferoxamine.

77. A method of collecting a biological analyte from blood, the method comprising: delivering a preservative system into a sample collection device; delivering the blood to the sample collection device; processing the blood to obtain a solution containing the biological analyte; and collecting the biological analyte; wherein the preservative system stabilizes the biological analyte for analysis.

78. The method of claim 77, wherein the biological analyte is selected from the group consisting of a metabolite, a lipid, a nucleic acid, and a protein.

79. The method of claim 77 or 78, wherein the biological analyte is selected from the group consisting of 2-Hydroxyglutaric acid, 2-Keto-glutaramic acid, 3-amino-lH- pyrazolo[4,3-c]pyridine-4,6-diol, 4-Hydroxy-2-oxoglutaric acid, 4-hydroxy-L-glutamate dianion, 4-Hydroxyphenyllactic acid, 4-Methyleneglutamic acid, 4-Nitroaniline, 4- Oxoproline, 5-Imino-L-norvaline, Alanine, Allantoin, alpha-Glutamyl-4-hydroxyproline, alpha-Ketoglutaric acid, Aspartic acid, beta-Aspartylaspartic acid, Cysteine, Cysteinesulfinic acid, Dihydrouridine, N-formylmethionine (fMet), gamma-Glutamyl-N5- acetylornithine, Glutamic acid, Glutamine, Glutamyl-L-glutamine, Glutathione (reduced), Glycine, Gly-pro, Hydroxyglutaric acid, leu-gln, Levulinic acid, Lysine, Mesaconic acid, N- Acetylalanine, N-Acetylglycine, N-Acetyl-L-aspartic acid, N-Acetyl-L-glutamic acid, N- Formylaspartate, N-Phenylacetylglutamine, Phosphocreatine, Proline, Prolylglycine, S- Lactoylglutathione, S-Sulfocysteine, Tartronic acid, Taurine, Threonic acid, trans- Glutaconic acid, 2,3-Dihydroxypropanoic acid, 2-[(2-Amino-2- carboxyethyl)thio]butanedioic acid, 2-Amino-4-(3-hydroxy-2-oxo-3-azetidinyl)butanoic acid, 2-Butynedioic acid, 2 -Hydroxy valeric acid, 2-Methyl-3 -hydroxybutyric acid, 2-Oxo-4- pentenoic acid, 2-Oxobutyric acid, 3,4-dihydroxyphenylacetic acid, 3,4-Methyleneazelaic acid, 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF), 3 -Hydroxy-2, 4- di oxopentyl phosphate, 3-hydroxy-2-methylbutyric acid, 3 -Hydroxy octanoic acid, 3- Hydroxyvaleric acid, 4,5-Dihydroxy-2,3-pentanedione, 4-Hydroxybenzoic acid, 4- Hydroxybutyric acid (GHB), 5-Hydroxydihydro-2,3-furandione, 5-Methoxy-3-indoleaceate, 6-Hydroxycaproic acid, 6-Oxohexanoic acid, Beta-Hydroxybutyric acid, diacetyl, Butenedioic acid, cis-2-hydroxypenta-2,4-dienoic acid, Ethylmalonic acid, Glycerophosphoglycerol, Imidazol-4-one-5-propionic acid, Isobutyric acid, Maleic acid, Malondialdehyde, Malonic acid, Pent-2 -ulosonic acid, 2,3-Bisphospho-D-glyceric acid, 3- O-beta-D-galactosyl-sn-glycerol, 3 -phosphoglyceric acid, beta-L-fucose 1 -phosphate, Fructose 1 -phosphate, Glucose, Glucose 1 -phosphate, Glucose- 1,6-bisphosphate, Glyceraldehyde, glyceraldehyde 3-phosphate, Glycerol 3-phosphate, glycolaldehyde phosphate, Glycolic acid, Iditol, Indole-3 -lactic acid, Lactic Acid, Mannitol 1 -phosphate, Phosphoenolpyruvic acid, Saccharolactone, Trehalose, Xylitol, 1 -myo-Inositol 1,2-cyclic phosphate, 2'-Deoxy-5'-inosinic acid, 2'-Deoxycytidine, 2-Methylhexahydro-4- pyrimidinecarboxylic acid, 2'-MONOPHOSPHOADENOSINE-5'-DIPHOSPHORIBOSE,Adenine, Adenosine 5'-tetraphosphate, Adenosine triphosphate (ATP), ADP, Allantoin, AMP, ATP, CDP, dADP, Deoxyadenosine 5'-triphosphate (dATP), Deoxyguanosine diphosphate (dGDP), Guanine, Guanosine 5'-diphosphate (GDP), Guanosine monophosphate (GMP), Guanosine triphosphate (GTP), Inosine-5'-monophosphate (IMP), Orotidine, Oxalic acid, Pl,P2-bis(5'-adenosyl) triphosphate, Pseudouridine, Uridine 5'- diphosphate (UDP), UMP, Uracil, Ureidosuccinic acid, Uric acid, 3-ADP-2- phosphoglyceric acid, ADP ribose, ADP-D-ribose l",2"-cyclic phosphate, CDP- ethanolamine, CMP-2-aminoethylphosphonate, Cyclic ADP-ribose, GDP-beta-L-colitose, Guanosine 5'-diphospho-D-mannose, Guanosine 5'-diphospho-B-L-fucose, Mannitol 1- phosphate, N-Acetyl-D-galactosamine 4-sulfate, N-Acetylglucosamine 1 -phosphate, N- Acetylglucosaminitol, N- Acetylneuraminic acid, N-Acetyl-a-D-glucosamine 1 -phosphate, Saccharolactone, Trehalose, UDP-galactose, UDP-N-acetylglucosamine, udp-glucuronic acid, UDP-N-acetylglucosamine, Uridine 5'-diphosphogalactose, l,3,4-Trihydroxy-5- oxocyclohexanecarboxylic acid, l-(malonylamino)cyclopropane-l -carboxylic acid, 1,5- Anhydro-D-glucitol, l-Deoxy-5-O-phosphonopent-2-ulose, 1 -deoxy -D-altro-heptulose 7- phosphate, l-deoxy-D-threo-hexo-2,5-diulose 6-phosphate, ID-myo-Inositol 1,2-cyclic phosphate, ID-Myo-inositol 1,3,4,5-tetrakisphosphic acid, 1-Methyluric acid, 1-0- Phosphonopentitol, 2, 3, -DIHYDROXYBENZOYLSERINE, 2,6-Diaminopimelic acid, 2- Acetamido-2-deoxy-l,6-di-O-phosphono-beta-D-glucopyranose, 2-Amino-6-(l,2- dihydroxypropyl)-4(lH)-pteridinon, 2-C-METHYL-D-ERYTHRITOL-2,4- CYCLOPYROPHOSPHATE, 2-deoxy-D-gluc-5-ulosonic acid, 2-phosphinomethylmalic acid, 3-(acetamidomethylidene)-2-(hydroxymethyl)succinic acid, 4- [Amino(carboxy)methyl]-5-oxoproline, 4-Hydroxy-2-butynal, 4-Hydroxyphenyllactic acid, 4-Methoxyaniline, 5 -Hydroxydihydro-2, 3 -furandione, 6-Deoxy-D-arabino-hexos-2-ulose, 6-O-Phosphonohex-2-ulofuranose, Ascorbic acid 2-sulfate, beta-D-Ethyl glucuronide, Crotonic acid, DEHYDROASCORBIC ACID, Diethylpyrocarbonate, dihydropyranone, Dyphylline, Ethyl sulfate, ethylenediaminetriacetic acid, furoic acid, Glucopyranose, Glucopyranuronic acid, Glycolic acid, Glyoxylic acid, Hexaric acid, Hydroxyglutaric acid, Isethionic acid, Lyxose, monomethyl phosphate, N-ethylmaleimide, Niacin, Nitrilotriacetic acid, ophthalmic acid, oxamate, oxazolidinone, phenyl-D-glucoside, Phosphocreatine, Phosphonoacetate, Phosphoric acid, Pyrogallol, Phosphoerythronic acid, Pyrophosphoric Acid, Tartaric acid, Tartronic acid, 5-O-[Hydroxy(phosphonooxy)phosphoryl]-beta-D- ribofuranose, 5-phospho-alpha-D-ribose cyclic- 1,2-phosphate, 6-0-Phosphono-alpha-D- glucopyranose, 6-0-Phosphono-D-gluconic acid, beta-D-Ethyl glucuronide, beta-D-Glucopyranuronic acid, D-4-PHOSPHOERYTHRONIC ACID, Erythorbic acid, Erythrose, Erythrose, 4-phosphate, Gluconic acid, Glucono-delta-lactone, Glucosamine 6-phosphate, glucosone, Glutaric acid, Glyoxylic acid, N-glycoloyl-beta-D-glucosamine, phenyl-D- glucoside, Ribonic acid, ribulose 5-phosphate, Sedoheptulose 7-phosphate, Xylose, Xylulose 5-phosphate, 4-Hydroxy-2-oxoglutaric acid, ACETOPYRUVIC ACID, Aconitic Acid, alpha-Ketoglutaric acid, Citraconic acid, Citric acid, Fumaric acid, Isocitric acid, Itaconic acid, Malic acid, Methyl pyruvate, NADH, NADPH, Pyruvic acid, and Succinic semialdehyde.

80. The method of any one of claims 77-79, wherein the preservative system comprises quercetin, BHT, phloroglucinol, alpha-cyclodextrin, Vitamin C, deferoxamine, SSA, DTP A, catechin, or a combination of any two or more thereof.

81. The method of any one of claims 67-70, wherein the preservative system comprises quercetin, BHT, and phloroglucinol.

82. The method of claim 81, wherein the preservative system further comprises DTPA.

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