Time-domain nmr method for differentiating materials

Abstract

Disclosed herein are methods useful for analyzing materials in a multiphasic solution (e.g. biphasic solution) using time-domain NMR (TD-NMR).

Description

[0001] TIME-DOMAIN NMR METHOD FOR DIFFERENTIATING MATERIALS

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to U.S. Provisional Application No. 63 / 532,782, filed on August 15, 2023, the entire contents of which are incorporated herein.

[0004] FIELD

[0005] In aspects, the disclosure provides a method to improve the ability of time-domain nuclear magnetic resonance (TD-NMR) to differentiate between liquid materials.

[0006] BACKGROUND

[0007] Nuclear Magnetic Resonance (NMR) examines the magnetic behavior of materials after the magnetic moments within have been manipulated in a magnetic field. Time-domain measurements, also known as NMR relaxometry, focus on the time for the perturbed system to return to its original state while in the applied field. The examination of such relaxations generally focuses on two types of interactions. The first, longitudinal (spin-lattice or Tl) relaxation, determines the rate for the magnetic system's return to energetic equilibrium after the perturbation. The second, transverse (spin-spin or T2), measures the time constant for the loss of coherence (fixed phase relationship) between the individual nuclear magnetic moments in the sample as they precess about the applied field.

[0008] T2 relaxation curves are analyzed by fitting to one or more exponential functions using iterative least squares. The extracted parameters for each function are a signal amplitude and a decay rate (or equivalently, its reciprocal, the decay time constant). When more than one decay rate is apparently detected, the results are typically checked to ensure that the conclusion of the presence of additional decays is statistically significant.

[0009] Dedicated TD-NMR instruments employ low field, permanent magnets, typically in the range from

[0010] 0.5 to 1.9 Tesla. The instruments are tuned to detect the response of specific atoms with nuclear magnetic moments. The magnets have inhomogeneities in the applied field, which can affect the resolution obtainable in various types of NMR experiments.

[0011] The magnetic properties of TD-NMR spectrometers limit the amount of information that can be gleaned about a sample. For example, it is unusual to detect more than 3 separate decays in a TD-NMR analysis. For this reason, TD-NMR is primarily employed to compare magnetic relaxations in different samples, rather than to provide a detailed characterization of a single material. In pure liquids, or liquids where the solvent contains the majority of the atoms with a nuclear magnetic moment, the observed relaxation is dominated by the solvent. In the case of solutions, the effect of solutes on the relaxation of the solvent is determined via the TD-NMR measurement.

[0012] The number of measurable parameters available in time-domain NMR to compare materials is small. Thus, there is a need in the art for novel methods that increase the total obtainable measurable parameters can improve the sensitivity and reliability of TD-NMR analyses. The present disclosure addresses this need in the art.

[0013] BRIEF DESCRIPTION OF THE FIGURES

[0014] Figs. 1A and IB illustrate an exemplary NMR system in accordance with various embodiments.

[0015] Fig. 2 is a graph of an exemplary T2 relaxation curve. Fig. 2 shows T2 relaxation and a numerical least-squares fit (red) to the observed decay curve.

[0016] Fig. 3 is a schematic representation of a non-limiting example of the sample and hardware used in a biphasic TD-NMR experiment.

[0017] DETAILED DESCRIPTION

[0018] In aspects, the disclosure provides a time-domain NMR method using a sample comprising one or more liquid phases (e.g. a biphasic system or multiphasic systems), in addition to the sample In embodiments, the additional phase(s) are immiscible with the material (e.g. the sample) and any other liquids used.

[0019] The time-domain version of nuclear magnetic resonance examines the relaxation of excited protons in the sample. The resulting decay curve is analyzed by curve-fitting to determine the relaxation time or times within the material. Differences in the composition of the sample are correlated with the observed relaxation. When more than a single relaxation time is detected in the sample, the relative amplitudes of each decay provide information on the amount of detected materials corresponding to each specific relaxation component. Unlike most conventional NMR experiments, time-domain NMR (TD-NMR) generally does not require the use of deuterated solvents.

[0020] Relaxations fall into 2 categories: longitudinal relaxation and transversal relaxation. Longitudinal relaxation, Tl, returns the perturbed spins to the distribution at thermal equilibrium, prior to the spins being manipulated. Transverse relaxation, T2, follows the loss of coherence (change in relative phase) between atomic magnetic moments oriented perpendicular to the applied field as the moments process about the applied field. The Tl relaxation rate is greater than the T2 rates in the same sample, as would be understood by one of ordinary skill in the art. graph of an exemplary T2 relaxation curve is shown in Fig. 2.

[0021] In aspects, the disclosure provides methods for analyzing a selected material using an NMR apparatus having a processor associated with a memory. An exemplary NMR apparatus is shown in FIGS. 1A and IB. FIGS. 1A and IB illustrate an exemplary NMR system 100 in accordance with various embodiments of the present disclosure including an NMR coil 102 surrounding a sample 104 being analyzed, a magnet 106 for generating a static magnetic field across the sample 104 and the coil 102, an RF transceiver 108 coupled to the NMR coil 102, and a controller 110 for controlling operation of the RF transceiver 108. In one implementation, the transceiver 108 includes a transmitter (Tx) portion 112 for generating and transmiting RF signals to the sample 104 and a receiver (Rx) portion 114 for receiving echo signals from the sample 104. Referring to FIG. 1A, during NMR measurements, the magnet 106 is activated to generate a substantially homogeneous magnetic field Bo across the sample 104; individual magnetic moments of the spins in the sample 104 may attemptto align with the applied field Bo. As a result, the magnetic moments of all the nuclei in the sample sum to a net magnetic moment that precesses about the axis of the field Bo at a characteristic Larmor frequency, OJO, satisfying UJO=Y Bo, where y is a gyromagnetic ratio. Because different nuclei have different values of the gyromagnetic ratio, measuring the Larmor frequency of the sample 104 allows material properties (e.g., the chemical composition) of the sample 104 to be revealed. In various embodiments, to observe precession of the net magnetic moment, the controller 110 causes the transmitter 112 to transmit an RF signal 116 (typically comprising a pulse sequence) having a resonant frequency substantially close (e.g., within ±10% or ±5%) to the Larmor frequency cooto the coil 102; the coil 102 then generates an RF magnetic field that causes the net magnetic moment of the nuclei in the sample 104 to be "tipped" away from the axis of the static field Bo. Typically, the RF magnetic field has a time-dependent magnitude and is generated in a plane perpendicular to the axis of the static field Bo. Referring to FIG. IB, after a predetermined time duration, At, the transmitter 112 stops transmission of the RF excitation signal 116, and the coil 102 is switched via, for example, a mechanical switch or an electrical switch (e.g., a transistor) to the receiver 114 for receiving the echo signals from the sample 104. In embodiments, the sample 104 is a polyphasic solution. Upon stopping the RF excitation, the nuclear spins within the sample 104 precess around the Bo-axis at the Larmor frequency OJO; this induces a corresponding signal oscillation. The nuclear spins then slowly lose phase coherence via spin-spin interactions, which manifest themselves in a macroscopic average as an exponential relaxation or damping signal 118 (referred to as "free induction decay") in the precession of the net magnetic moment. The oscillation and relaxation of the NMR signal can be detected by the coil 102. Because the spin-spin interactions are peculiar to the material of the sample 104 being tested, the characteristic time, commonly referred to as T?, of the relaxation signal is also material-specific. Thus, by measuring the Larmor frequency ooo (e.g., for spectroscopy) and / or characteristic time T2 (e.g., for relaxometry), NMR techniques can be used as an analytic tool in a number of fields, including but not limited to chemical composition analysis, medical imaging, and bio-sensing. An exemplary NMR system is described in U.S. Pat. No. 8,643,368, the entire disclosure of which is hereby incorporated by reference.

[0022] Liquid samples containing multiple phases have been examined by NMR in the literature. In those experiments, however, only one of the phases was analyzed within the magnetic field of the spectrometer. In embodiments, the volumes of all phases (e.g. all phase of a biphasic system or multiphasic system) are in the magnetic field and detection coil of the instrument. A non-limiting example of this arrangement is illustrated in Fig. 3.

[0023] The observed decay rates in a TD-NMR analysis usually depend on the temperature at which the experiment is executed. In embodiments, in the methods of the disclosure, TD-NMR comparisons between samples are all performed at the same temperature or a calibration for the standard materials is used that takes into account the varying temperatures. In embodiments, in the methods of the disclosure, the calibration involves fitting observed rates as a function of temperature to a linear or higher order function to produce a curve. In embodiments, this curve can then be used to determine whether rates measured at different temperatures correspond to the same or similar samples. In embodiments, the temperature calibration involves a distribution of rates at a given temperature, to account for random differences in experimentally determined values when multiple replicates are performed at that temperature.

[0024] In embodiments, the sample and added phases (e.g. a biphasic system or multiphasic systems) of the disclosure meet the following criteria:

[0025] 1) The selected materials are liquid solvents (e.g. organic liquids) or solutions;

[0026] 2) The sample (e.g. first phase of the multiphasic solution) and additional liquids (i.e. the second phase and / or additional phases of the multiphasic solution) are immiscible; and 3) At least one constituent of the sample has solubility in the second phase and / or additional phases of the multiphasic solution.

[0027] In embodiments, the solubility of the constituent results in a partiboning of material between the liquids, providing a change in composition of the added liquid results in a change in the decay rate of the second phase.

[0028] In a non-limiting example, in the analysis of a sample alone in a monophasic system, a set of decay rates and (relative) amplitudes is obtained. In embodiments, the use of additional phases (e.g. a biphasic system or multiphasic system) provides at least one decay rate and at least one amplitude from each liquid added to the sample, increasing the number of parameters extracted from the method. In embodiments, when the third criterion is met (i.e. at least one constituent of the sample has solubility in the added phase), the additional values be useful for characterizing the original sample; otherwise,, the extracted parameters for the added phase, and the original sample, will be the same as the extracted parameters for each phase individually, and would not yield additional information on the sample (e.g. characterization of the sample). In embodiments, comparison of the extracted decay rates with the decay rates of the original monophase liquids provides a rapid assessment of the success of the experiment.

[0029] Additional Exemplary Polyphasic Solution Analysis Methods

[0030] In embodiments, the method includes providing a polyphasic solution comprising the selected material to the NMR apparatus. An example of the polyphasic solution comprising the selected material in the NMR apparatus is shown in FIG. 3. Embodiments of the polyphasic solution are described in further detail below.

[0031] In embodiments, the method includes subjecting the polyphasic solution comprising the selected material to NMR readings from an NMR apparatus (e.g., NMR system 100) as a function of time from at least one NMR signal of the selected material. In embodiments, the method includes providing a multiphasic solution comprising the selected material to the NMR apparatus. Embodiments of the multiphasic solution are described in further detail below.

[0032] In embodiments, the method includes subjecting the multiphasic solution comprising the selected material to NMR readings from an NMR apparatus as a funchon of time from at least one NMR signal of the selected material.

[0033] In embodiments, the method includes generating time domain data representing signal dependence on decay rates.

[0034] In embodiments, the method includes deriving, from the time domain data generated from the at least one NMR signal, for each phase of the multiphasic solution, one or more representative amplitudes representative of one or more amplitude values and one or more decay rates. In embodiments, representative amplitudes may refer to a difference between two or more amplitudes for a respective phase. As described herein, one of the advantages of performing the NMR readings on a biphasic solution is the ability to extract multiple amplitudes representative of the amplitude values and the decay rates of the selected material in each phase (e.g., aqueous and organic in the non-limiting representative example described herein).

[0035] In embodiments, the method further comprises determining the one or more representative amplitudes and the one or more relaxation rates meets results criteria. In embodiments, a results criterion is met under the condition that the representative amplitudes for each phase fall within a predetermined material indication range. The predetermined material indication range may be particular for each representative amplitude. In embodiments, a results criterion is met under the condition that the representative amplitudes correlate with the representative amplitudes of a particular training material. In embodiments, a results criterion may be the identification of a characteristic about the selected material. Selected Material

[0036] Any material that is capable of being analyzed by NMR (e.g. TD-NMR) is contemplated by the present disclosure, as would be understood by one of ordinary skill in the art. In embodiments, the selected material is or comprises a small molecule or a biological molecule. Non-limiting examples of biological molecules include a lipid, a protein, a peptide, a nucleic acid, a polysaccharide, and a carbohydrate. In embodiments, the biological molecule is naturally- occurring. In embodiments, the biological molecule is chemically synthesized. In embodiments, the selected material is or comprises a bacterial polysaccharide.

[0037] In embodiments, the selected material is or comprises an organic liquid. Any organic liquid is contemplated by the present disclosure. In a non-limiting example, the methods of the disclosure are useful to analyze (e.g. identify) organic liquids, for example in the presence of an additional phase (e.g. an aqueous phase), which may optionally be a pure organic liquid (i.e. free of or substantially free of impurities or other materials) or contain additional constituents.

[0038] Non-limiting examples of hydrocarbons include n-hexane, cyclohexane, dodecane, and pentadecane.

[0039] Non-limiting examples of aromatic hydrocarbons include benzene, toluene, xylene, solvent naphtha, and styrene.

[0040] Non-limiting examples of alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, isobutyl alcohol, 2-butanol, ethylene glycol, glycerin, propylene glycol, triethylene glycol, polyethylene glycol, benzyl alcohol, 1,5-pentanediol, and diacetone alcohol.

[0041] Non-limiting examples of esters include ethyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, and propylene glycol monomethyl ether acetate. Non-limiting examples of ethers include diethyl ether, dibutyl ether, tetrahydrofuran, dioxane, ethylene glycol monomethyl ether, ethylene glycol monopropyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether.

[0042] Non-limiting examples of aldehydes include formaldehyde, acetaldehyde, acrolein, propionaldehyde and crotonaldehyde.

[0043] Non-limiting examples of ketones include acetone, methyl ethyl ketone, 2-pentanone, 3- pentanone, methyl isobutyl ketone, 2-heptanone, and cyclohexanone.

[0044] Non-limiting examples of halogenated (e.g. chlorinated) hydrocarbons include chloroform, dichloromethane and trichloroethylene.

[0045] Non-limiting examples of organic acids include acetic acid, formic acid, p-toluene sulfonic acid, citric acid, gluconic acid, maleic acid, and propionic acid.

[0046] Non-limiting examples of amides include acetamide, N,N-dimethylformamide, N,N- dimethylacetamide, and N-methylpyrrolidone.

[0047] Non-limiting examples of nitriles include acetonitrile, glutaronitrile, methoxyacetonitrile, propionitrile, and benzonitrile.

[0048] Examples of other organic solvents include dimethylsulfoxide or other nitrogen-containing groups (e.g. pyridine).

[0049] In embodiments, the selected material is or comprises hydrocarbons (e.g. C5-C20 hydrocarbons such as dodecane or pentadecane), ethers (e.g. diethyl ether or petroleum ether), aromatic hydrocarbons (e.g. benzene, toluene), alcohols (e.g. methanol, ethanol), esters (e.g. ethyl acetate), ethers (e.g. diethyl ether), aldehydes (e.g. formaldehyde), ketones (e.g. acetone), chlorinated hydrocarbons (e.g. C1-C20 chlorinated hydrocarbons such as chloroform), organic acids (e.g. acetic acid), amides (e.g. N,N-dimethylformamide), nitriles (e.g. acetonitrile), or other nitrogen-containing groups (e.g. pyridine), and combinations thereof.

[0050] In embodiments, the organic liquid of the selected material is or comprises dodecane and / or pentadecane.

[0051] Multiphasic Solution

[0052] In aspects, the disclosure provides a multiphasic solution that is useful within the methods of the disclosure. In embodiments, the multiphasic solution comprises or consists of about two phases (i.e. a biphasic solution), about three phases, about four phases, about five phases, or more than five phases. In a non-limiting example, while in the analysis of a signal from a liquid having a single phase (i.e. monophasic solution) only two parameters, amplitude and rate, are available, a multiphasic solution provides an exponential increase in the number of parameters. In a nonlimiting example, a two-phase (biphasic) experiment doubles the number of parameters. While not wishing to be bound by any particular theory, an underlying principle, the movement of constituents into a different liquid phase, is the same as that employed in extraction-based purifications in organic chemistry.

[0053] In embodiments, the multiphasic solution comprises or consists of one or more of a first phase, a second phase, a third phase, a fourth phase, and a fifth phase. In embodiments, the multiphasic solution comprises a first phase and a second phase. In embodiments, the multiphasic solution comprises a first phase and a second phase, and is a biphasic solution.

[0054] In embodiments, the multiphasic solution comprises one or more phases that are immiscible or substantially immiscible with the remaining phases of the multiphasic mixture and / or the selected material. In embodiments, the multiphasic solution comprises a first phase and a second phase, wherein the first phase is immiscible or substantially immiscible with the second phase. In embodiments, the multiphasic solution comprises a first phase and a second phase, wherein the first phase is immiscible or substantially immiscible with the second phase and the selected material. In embodiments, the multiphasic solution comprises a first phase and a second phase, wherein the first phase is immiscible or substantially immiscible with the second phase and the second phase is immiscible or substantially immiscible with the selected material. In a nonlimiting example, the method includes combining a first phase with second phase, which is immiscible with the selected material, to form a biphasic solution.

[0055] In embodiments, a portion of the selected material present in the first phase transfers to the second phase. In a non-limiting example, in a biphasic solution comprising a first phase comprising the selected material and a second phase that is immiscible with the first phase, the transfer of a portion of the selected material from the first phase into the second phase provides, in part, the increase in the number of parameters identified from the signal.

[0056] In embodiments, one or more phases of the multiphasic mixture (e.g. the first phase and / or the second phase) comprise a transfer enhancing material. As used herein, a "transfer enhancing material" refers to a material that is capable of enhancing and / or facilitating transfer of a selected material from one phase to another phase, for example by chemically reacting with the selected material. In embodiments, the transfer enhancing material reacts with the selected material such that the selected material or a portion of the selected material is capable of transferring and / or migrating from one phase to another phase (e.g. from the first phase to the second phase, or from the second phase to the first phase). In a non-limiting example, a first phase comprises olive oils, which contain fats (esters of fatty acids and glycerol). The first phase is treated with an alkaline solution (e.g. aqueous sodium hydroxide) to form an aqueous second phase, and the alkaline solutions saponifies some or all of the esters to provide fatty acids and glycerol. The fatty acids and glycerol are more polar than the fats (i.e. esters) and therefore more likely to transfer to the aqueous second phase, and the methods closed herein can be used to analyze (e.g. differentiate between) the different olive oils. In embodiments, the solubility of the selected material results in a partitioning of material between the liquids, providing a change in composition of the added liquid results in a change in the decay rate of the second phase (or any other phase of a multiphasic solution).

[0057] In embodiments, one or more phases of the multiphasic solution is an organic phase, and one or more phases of the multiphasic solution is an aqueous phase. In embodiments, the first phase of the multiphasic solution is an aqueous phase, and the second phase of the multiphasic solution is an organic phase. In embodiments, the first phase of the multiphasic solution is an organic phase, and the second phase of the multiphasic solution is an aqueous phase.

[0058] In embodiments, the organic phase is or comprises hydrocarbons (e.g. C5-C20 hydrocarbons such as dodecane or pentadecane), ethers (e.g. diethyl ether or petroleum ether), aromatic hydrocarbons (e.g. benzene, toluene), alcohols (e.g. methanol, ethanol), esters (e.g. ethyl acetate), ethers (e.g. diethyl ether), aldehydes (e.g. formaldehyde), ketones (e.g. acetone), chlorinated hydrocarbons (e.g. C1-C20 chlorinated hydrocarbons such as chloroform), organic acids (e.g. acetic acid), amides (e.g. N,N-dimethylformamide), nitriles (e.g. acetonitrile), or other nitrogen-containing groups (e.g. pyridine), and combinations thereof. Non-limiting examples are disclosed above. In embodiments, the organic phase is or comprises dodecane and / or pentadecane.

[0059] In aspects, the volume of each phase of the multiphasic solution (i.e. the total volume of the multiphasic solution) is within or substantially within the detection volume of the NMR apparatus (e.g. TD-NMR spectrometer). In embodiments, maintaining the total volume of the multiphasic solution within or substantially within the detection volume of the NMR apparatus permits the use of the amplitude parameters in the comparisons. In embodiments the volume of each phase of the multiphasic solution is within or substantially within a coil of the NMR apparatus. Methods for maintaining the volume of each phase of the multiphasic solution within or substantially within the detection volume of the NMR apparatus include, but are not limited to, using a volume of a multiphasic mixture of a height that when added to a vessel and / or container (e.g. an NMR tube) placed within NMR apparatus (e.g. within a coil), the volume remains within the detection volume. In a non-limiting example, a NMR tube comprising the multiphasic mixture is placed within a coil of the NMR apparatus such that the height of the multiphasic mixture in the NMR tube is not greater than the top of the coil. In embodiments, the volume of the first phase of the multiphasic mixture and the volume of the second phase of the multiphasic mixture are within or substantially within the detection volume of the NMR apparatus.

[0060] In embodiments, the volume of each phase of the multiphasic system ranges from about 1 pL to about 20 pL, about 1 pL to about 15 pL, about 1 pL to about 10 pL, about 5 pL to about 10 pL, about 6 pL to about 8 pL, or about 7 pL to about 8 pL. In embodiments, the volume of each phase of the multiphasic system is about 1 pL, about 1.5 pL, about 2 pL, about 2.5 pL, about 3 pL, about 3.5 pL, about 4 pL, about 4.5 pL, about 5 pL, about 5.5 pL, about 6 pL, about 6.5 pL, about 7 pL, about 7.5 pL, about 8 pL, about 8.5 pL, about 9 pL, about 9.5 pL, about 10 pL, about 11 pL, about 12 pL, about 13 pL, about 14 pL, about 15 pL, about 16 pL, about 17 pL, about 18 pL, about 19 pL, or about 20 pL.

[0061] As would be understood by one of ordinary skill in the art, TD-NMR is a comparative or relative technique, and data from reference materials (i.e. reference standards) are necessary. Any reference standard is useful in the disclosure. In embodiments, the reference standard is or comprises a pure material (i.e. a material free of or substantially free of impurities or other materials) and / or liquid (e.g. purified water), a mixture of materials at known volumes and / or masses, or a solution comprising a material at a known concentration and / or content. In embodiments, one or more phases of the multiphasic mixture is or comprises a reference standard. In embodiments, the first phase is a reference standard. In embodiments, the second phase is a reference standard.

[0062] EXAMPLES

[0063] EXAMPLE 1: Non-limiting Example of TD-NMR Method of the disclosure

[0064] The instrument employed provides as homogeneous a magnetic field as possible to the sample. In a non-limiting example, a homogeneity of 100 ppm or more of the sample permits the extraction of high quality data, . The uniformity (homogeneity) can be achieved by using a sample volume (e.g. volume of each phase in a multiphasic system) small relative to the length of the coil of the magnet (e.g., about 1 pl to about 10 pl, such as about 7.5 pl for each phase of the multiphasic system). The Example described herein used a Formula spectrometer manufactured by Waveguide Corporation. The instrument includes an approximately 0.5 Tesla magnetic, which corresponds to a Larmor frequency of approximately 21 MHz when tuned for hydrogenXH nuclei.

[0065] 1) Using a micro-pipettor, dispense 7.5 pL of the sample into a glass tube, 3 mm in diameter.

[0066] 2) Using a fresh, clean tip in the pipettor, dispense the same volume, 7.5 pL, of an immiscible liquid into the same tube.

[0067] 3) Agitate the tube with a vortex mixer to ensure maximum possible contact between the immiscible fluids.

[0068] 4) Optionally, a centrifuge is used to cause all liquid to be at the bottom of the sample tube.

[0069] 5) Place the tube into the spectrometer, checking that the tube is at the bottom of the sample holder.

[0070] 6) Collect relaxation data using a Carr-Purcell-Meiboom-Gill pulse sequence setting the following types of parameters. Non-limiting examples of values, which can depend on the sample and instrument, are provided in parenthesis. a. Echo period (500 psec) b. Number of scans (2) c. Recycle delay (12 sec) d. Sample rate (125000 hertz) e. Scan duration (15 sec) f. 90 degree pulse width (22 psec)

[0071] 7) Using non-linear least squares fitting procedures, extract the decay rate and exponential parameters for 2 or more exponential functions from the observed relaxation curve.

[0072] 8) Compare the observed decay rates and relative amplitudes with those of a known reference or references. In embodiments, the reference can be characterized by a range of values previously obtained from multiple determinations. In embodiments, the ranges include consideration of appropriate statistical parameters and optionally the effect of varying temperatures. In embodiments, where statistical data are not available or limited, additional methods can be used to determine the acceptable difference between sample and reference, as would be understood by one of ordinary skill in the art.

Claims

CLAIMSWhat is claimed is:

1. A method for analyzing a selected material using an NMR apparatus having a processor associated with a memory, comprising: providing a multiphasic solution comprising the selected material to the NMR apparatus; subjecting the multiphasic solution comprising the selected material to NMR readings as a function of time from at least one NMR signal of the selected material and generating time domain data representing signal dependence on decay rates, and deriving, from the time domain data generated from the at least one NMR signal, for each phase of the multiphasic solution, one or more representative amplitudes representative of one or more amplitude values and one or more decay rates.

2. The method of claim 1, wherein the method further comprises determining the one or more representative amplitudes and the one or more relaxation rates meets results criteria; generating a result from the one or more representative amplitudes representative of one or more amplitude values and one or more decay rates and outputting the result; and in response to a determination that the one or more representative amplitudes and the one or more relaxation rates meets results criteria, output a result on a user interface indicative that the one or more representative amplitudes and the one or more relaxation rates met the results criteria, optionally wherein the one or more relaxation rates are determined based on at least one or more of the following parameters.

3. The method of claim 1 or 2, wherein a time duration between each point of the time domain data is varied.

4. The method of claim 3, further comprising after the correlating step, determining decay rates for each phase of the multiphasic solution.

5. The method of any one of claims 1-4, wherein outputting the result indicative that the one or more representative amplitudes and the one or more relaxation rates met the results criteria includes at least one of: (i) a characterization of the selected material, and (ii) an identity of the selected material and / or an identification of the content of the selected material.

6. The method of any one of claims 1-5, wherein one of the one or more representative amplitudes is a relative amplitude between a first amplitude of a first phase and a second amplitude of a second phase.

7. The method of any one of claims 1-6, wherein the selected material is or comprises a small molecule or a biological molecule, optionally wherein the biological molecule is selected from a lipid, a protein, a peptide, a nucleic acid, a polysaccharide, and a carbohydrate.

8. The method of claim 7, wherein the selected material is or comprises a bacterial polysaccharide.

9. The method of any one of claims 1-8, wherein the selected material is or comprises an organic liquid.

10. The method of claim 9, wherein the organic liquid of the selected material is or comprises hydrocarbons (e.g. C5-C20 hydrocarbons such as dodecane or pentadecane), ethers (e.g. diethyl ether or petroleum ether), aromatic hydrocarbons (e.g. benzene, toluene), alcohols (e.g. methanol, ethanol), esters (e.g. ethyl acetate), ethers (e.g. diethyl ether), aldehydes (e.g. formaldehyde), ketones (e.g. acetone), chlorinated hydrocarbons (e.g. C1-C20 chlorinated hydrocarbons such as chloroform), organic acids (e.g. acetic acid), amides (e.g. N,N- dimethylformamide), nitriles (e.g. acetonitrile), or other nitrogen-containing groups (e.g. pyridine), and combinations thereof.

11. The method of claim 10, wherein the organic liquid of the selected material is or comprises dodecane and / or pentadecane.

12. The method of any one of claims 1-11, wherein the multiphasic solution comprises a first phase and a second phase.

13. The method of claim 12, wherein the multiphasic solution is a biphasic solution.

14. The method of claim 12 or 13, wherein the first phase and / or the second phase comprises a transfer enhancing material.

15. The method of claim 14, wherein the transfer enhancing material reacts with the selected material such that the selected material or a portion of the selected material is capable of transferring and / or migrating from the first phase to the second phase, or from the second phase to the first phase.

16. The method of any one of claims 12-15, wherein the first phase of the multiphasic solution is an aqueous phase, and the second phase of the multiphasic solution is an organic phase.

17. The method of any one of claims 12-15, wherein the first phase of the multiphasic solution is an organic phase, and the second phase of the multiphasic solution is an aqueous phase.

18. The method of claim 16 or 17, wherein the organic phase is or comprises hydrocarbons (e.g. C5-C20 hydrocarbons such as dodecane or pentadecane), ethers (e.g. diethyl ether or petroleum ether), aromatic hydrocarbons (e.g. benzene, toluene), alcohols (e.g. methanol, ethanol), esters (e.g. ethyl acetate), ethers (e.g. diethyl ether), aldehydes (e.g. formaldehyde), ketones (e.g. acetone), chlorinated hydrocarbons (e.g. C1-C20 chlorinated hydrocarbons such as chloroform), organic acids (e.g. acetic acid), amides (e.g. N,N-dimethylformamide), nitriles (e.g. acetonitrile), or other nitrogen-containing groups (e.g. pyridine), and combinations thereof.

19. The method of claim 18, wherein the organic phase is or comprises dodecane and / or pentadecane.

20. The method of any one of claims 12-19, wherein the volume of the first phase and the volume of the second phase are within or substantially within the detection volume of the NMR apparatus, optionally wherein the detection volume is within or substantially within a coil.

21. The method of any one of claims 12-20, wherein the first phase is a reference standard.

22. The method of any one of claims 12-20, wherein the second phase is a reference standard.

23. The method of claim 21 or 22, wherein the reference standard is or comprises a pure material and / or liquid (e.g. purified water), a mixture of materials at known volumes and / or masses, or a solution comprising a material at a known concentration and / or content.

24. The method of any one of claims 1-23, wherein: a) the selected material is a liquid solvent (e.g. organic liquid) or a solution; b) the first phase is immiscible with the second phase and / or additional phases of the multiphasic solution; and c) at least one constituent of the sample has solubility in the second phase and / or additional phases of the multiphasic solution.

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