Human body fluid and excrement preservation system and method and application

Abstract

The invention provides a human body fluid and excrement preservation system and method and application, the preservation system comprises a sample box body, a sample carrier used for bearing samples is arranged in the sample box body, the sample carrier divides the internal space of the sample box body into a sample area and a drying area, and the sample area and the drying area are arranged in the sample box body. The sample box body is provided with a drying area, the drying area is filled with a first drying agent, the first drying agent is not in contact with the sample carrier, the sample carrier has water absorption and air permeability, and the sample box body is provided with a sealing structure. The application range is expanded in a separated drying mode, and solid samples and liquid samples can be preserved.

Description

Technical Field

[0001] The present invention relates to the field of biology and disease diagnosis technology, and in particular to a system, method and application for preserving human body fluids and excrement. Background Art

[0002] Human excrement contains a large amount of biological information, including organ lesions and bleeding, abnormal reproduction of microorganisms, abnormal increase or decrease of metabolites, etc. This information is closely related to human health. Detecting and monitoring these biomarkers can timely understand personal health status and disease development. At present, routine stool and urine tests in hospitals and physical examination centers should be cheap and efficient, and are very popular among doctors and patients. However, since such tests often require patients to go to hospitals or physical examination centers in person to collect samples, the time cost is very high, especially in some countries and regions with insufficient medical resources, a large number of ordinary people cannot enjoy this cheap and efficient physical examination service.

[0003] With the booming development of the express delivery industry, it has become possible to collect samples at home and then send them to a testing center for testing. At present, technological breakthroughs have been made in DNA stabilizers for human feces and urine, and a large number of home sampling and testing products for colorectal cancer have been launched on the market. Compared with DNA stabilizers, protein stabilizers are much more difficult. Taking fecal samples as an example, in order to inhibit the activity of DNA enzymes and the reproduction of bacteria, a strong denaturant can solve all problems, and this denaturant itself will not affect the biological activity of DNA and can be used as a DNA stabilizer. However, denaturants are fatal to the biological activity of proteins, and the stability of proteins themselves is far less than that of DNA. Therefore, how to ensure the stability of protein components in feces and urine, but at the same time inhibit bacterial growth and the activity of various proteases, is still a technical problem.

[0004] There are many products on the market for human stool sample stabilizers. For example, the product "Cologuard" from Precision Science contains a DNA stabilizer and a separate protein stabilizer. The protein stabilizer can ensure that the hemoglobin in the stool sample is stable during transportation at room temperature for 3 days, but it cannot be guaranteed for more than 3 days, so the sample must be mailed to the laboratory within 3 days; Japan Rongyan's OC-sensor contains a stool sample sampling bottle, in which the stabilizer can ensure that the hemoglobin in the stool sample is stable at room temperature for about 2 weeks, but the stability is poor at 37 degrees, and it degrades severely over time. The above methods are more suitable for community sampling and centralized testing. If the mailing time of the sample is long and the temperature conditions are not fixed, these products have hidden dangers. In addition, the temperature differences in different regions and seasons are large, especially in summer, which is a huge test for these products. Therefore, the development of a stabilizer that is resistant to high temperatures and has good stability is the key to realizing the home sampling service model.

[0005] The Chinese patent document discloses "a method for processing fecal samples and its application", and its publication number is CN104931314A. The patent discloses a simple and effective method for stabilizing fecal samples. The method is low-cost, easy to use, and can meet the needs of qualitative detection of hemoglobin. It has been widely used in the colorectal cancer screening market. However, this method can only meet the needs of qualitative detection, while quantitative FIT requires more stable samples and more reliable data, so the method needs to be greatly optimized and improved. According to the method recorded in the patent, the fecal sample has good stability after drying, but during the period before drying, the stability is poor and the protein degradation is serious. As for how to quickly obtain a dried fecal sample, the patent has not found a solution. On the other hand, the degree of drying of the sample directly affects its stability. However, the method recorded in the patent can only ensure that the water content of the sample is less than 10%, and the drying is not completely thorough, which is one of the reasons why the stability of the method is not satisfactory. Therefore, how to quickly and thoroughly dry the sample is a problem that needs to be solved at present. In addition, the patent has the technical problem of limited application scope by adding desiccant into the container to form a mixture of feces and desiccant, and is not suitable for stable processing of liquid samples. Human body fluids, especially urine, are biological samples rich in information and have important clinical detection significance, but there is still a lack of an effective preservation method. Summary of the invention

[0006] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a system, method and application for preserving human fluids and excrement, which is used to solve the problem that the existing fecal sample processing method has poor sample stability under storage conditions above 37°C, in different regions, different mailing times, different seasons, and different transportation conditions, and is not suitable for the preservation of liquid samples.

[0007] To achieve the above-mentioned purpose and other related purposes, the present invention provides a method for improving the storage stability of human body fluids and excrement, wherein the human body fluids and / or excrement samples are first quickly dehydrated and then thoroughly dehydrated to achieve stable storage of the human body fluids and / or excrement samples.

[0008] The present invention also provides a system for preserving human body fluids and excrement, comprising a sample box body, wherein a sample carrier for carrying samples is provided in the sample box body, wherein the sample carrier divides the internal space of the sample box body into a sample area and a drying area, wherein the drying area is filled with a first desiccant, wherein the first desiccant is in non-contact with the sample carrier, wherein the sample carrier has water absorption and air permeability, and wherein the sample box body has a sealing structure.

[0009] The sample preservation device of the prior art can only preserve solid samples, such as solid fecal samples. The human body fluid and excrement preservation system of the present application expands the scope of application through a separate drying method, and can preserve both solid samples and liquid samples, such as human urine samples. The preservation system of the present application is a completely closed container. When applied to the preservation of liquid samples, the liquid sample can be quickly dispersed on a sample carrier with water absorption and air permeability. The sample carrier is a dense, porous, and breathable material. The liquid sample dripped onto the carrier will quickly disperse under the capillary action and evenly adhere to the carrier. In this process, the sample will reach a relatively dry state and achieve instant preliminary drying. The sample on the sample carrier exchanges gas with the desiccant in the sample box body, and further combined with the non-contact water absorption effect of the desiccant, the sample on the sample carrier is completely and quickly dehydrated, and the long-term stability of the sample is achieved. The protein components in the sample preserved by the preservation system of the present application will not be denatured and inactivated due to being in a completely dehydrated state, and will not affect subsequent detection.

[0010] The sample carrier in this application has two functions: to quickly disperse the sample in the early stage and instantly achieve the initial drying effect; in the later stage, due to its air permeability and porosity, it is conducive to gas exchange and can be quickly and thoroughly dehydrated by the desiccant. The preservation system of this application can achieve the absolute stability of samples under different conditions, eliminate the differences between samples caused by different regions, different mailing times, different seasons, and different transportation conditions, ensure the reliability of clinical testing, meet the stability of samples under different regions and seasonal conditions of community services, and meet the stability of samples during long-distance mailing in uncertain environments after home sampling.

[0011] More preferably, the first desiccant occupies 2 / 3 of the volume of the drying zone, thereby preventing the first desiccant from being overfilled and causing contact with the sample carrier.

[0012] Preferably, a first air permeable filter is provided below the sample carrier, and the first air permeable filter is fixed to the inner wall of the sample box body. The first air permeable filter can ensure that the first desiccant and the sample are not in contact, but the gas exchange is good.

[0013] Preferably, the inner wall of the sample box body also includes a carrier support net arranged above the first air permeable filter net, and the sample carrier is fixed at the center of the carrier support net. The sample carrier is non-contact with the inner wall of the sample box body, thereby allowing the air inside the sample box body to have good circulation and improving the drying efficiency.

[0014] Preferably, the sample box body is provided with a sealing cover, a filling tube with a hollow hole structure is provided at the bottom of the sealing cover, the filling tube is filled with a second desiccant, and the second desiccant is in non-contact with the sample carrier.

[0015] The sealing cover can ensure that the inside of the sample box body is isolated from the external air, and filling the sealing cover with a second desiccant can further improve the drying effect of the sample.

[0016] Preferably, a second air permeable filter is provided between the filling tube and the sample carrier, which can ensure that the second desiccant and the sample are not in contact, but the gas exchange is good.

[0017] Preferably, at least one of the first desiccant and the second desiccant reacts irreversibly with water molecules.

[0018] Preferably, the first desiccant and the second desiccant are selected from one or both of a chemical desiccant and a physical desiccant, and at least include a chemical desiccant.

[0019] More preferably, the chemical desiccant is calcium oxide.

[0020] More preferably, the physical desiccant is activated alumina or anhydrous calcium chloride.

[0021] Chemical desiccants and physical desiccants can be used together. Chemical desiccants combine all the water in the sample box through chemical reactions, completely dehydrating the sample on the sample carrier and ensuring that the water in the container is completely absorbed. Physical desiccants use porous, large surface area materials to assist in rapid water absorption. Sometimes calcium oxide alone can also achieve the desired effect.

[0022] Preferably, the sample carrier is made of cellulose or animal hair.

[0023] More preferably, the sample carrier is made of industrial wool felt.

[0024] The present invention also provides a method for preserving human body fluids and excrement, which uses the human body fluid and excrement preservation system to place human body fluid or excrement samples on the surface of a sample carrier and seal the sample box body.

[0025] Preferably, when the storage environment temperature is greater than 37°C, a sample pretreatment step is also included, in which a buffer solution containing a protein protectant is added to the human body fluid or excrement sample. The use of the buffer solution can improve the stability of the sample before complete dehydration, and cooperate with the storage system to achieve an auxiliary stabilization effect.

[0026] The existing technology can only achieve sample stability at 37°C, and cannot guarantee sample stability at higher temperatures. In the process of mailing samples, in some cases, such as summer highway transportation, the temperature in the mailing vehicle may reach 60°C or above for a short time. The existing technology will fail to preserve samples, resulting in unknown test errors. The preservation system of the present invention combined with the preservation method can still guarantee 70% stability of the sample at 65°C.

[0027] More preferably, the protein protective agent is selected from one or more of bovine serum albumin, trehalose, heme and protease inhibitors.

[0028] The present invention also provides an application of the human body fluid and excrement storage system in medical testing.

[0029] As described above, the present invention has the following beneficial effects: (1) The application range has been expanded through the separate drying method, which can preserve both solid samples and liquid samples, such as human urine samples; (2) The storage system of the present application is a completely closed container. When used for the storage of liquid samples, the liquid samples can be quickly dispersed on the sample carrier with water absorption and air permeability. The sample carrier is a dense, porous, air-permeable material. When the liquid sample is dripped onto the carrier, it will quickly disperse under the action of capillary and evenly adhere to the carrier. During this process, the sample will reach a relatively dry state and achieve instant initial drying. The sample on the sample carrier exchanges gas with the desiccant in the sample box body. Further combined with the non-contact water absorption effect of the desiccant, the sample on the sample carrier can be completely and quickly dehydrated, achieving long-term stability of the sample. (3) The biological components in the samples preserved by the preservation system of the present application are in a completely dehydrated state and will not be denatured or inactivated, which will not affect subsequent testing. It has broad application prospects in the field of medical testing; (4) When the storage environment temperature is greater than 37°C, the present application adds a buffer containing a protein protectant to the human body fluid or excrement sample through a pretreatment process. The buffer can improve the stability of the sample before it is completely dehydrated and cooperate with the storage system to play an auxiliary stabilization effect; (5) In the liquid storage method commonly used in the prior art, proteins begin to denature and become inactivated at temperatures above 50°C, and most species can be completely denatured at temperatures above 60°C, which will lead to failure or error in subsequent testing. In the method of the present invention, the protein components in the sample are in a completely dehydrated state and will not denature and become inactivated, which will not affect subsequent testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Shown is a schematic diagram of the structure of the human body fluid and excrement storage system of Example 1.

[0031] Figure 2 Shown is a schematic diagram of the structure of the human body fluid and excrement storage system of Example 2.

[0032] Figure 3 Shown is a line graph showing the change in hemoglobin content over time in simulated stool samples at different temperatures.

[0033] Figure 4Shown is a line graph showing the change in hemoglobin content over time in simulated urine samples at different temperatures.

[0034] Description of the accompanying drawings: sample box body 1, sample area 11, drying area 12, first desiccant 121, sealing cover 13, filling tube 14, second desiccant 141, sample carrier 2, first air permeable filter 3, carrier support net 4. DETAILED DESCRIPTION

[0035] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0036] It should be noted that the process equipment or devices not specifically specified in the following embodiments are all conventional equipment or devices in the art.

[0037] In addition, it should be understood that one or more method steps mentioned in the present invention do not exclude the existence of other method steps before or after the combination step or the insertion of other method steps between these explicitly mentioned steps, unless otherwise specified; it should also be understood that the combination connection relationship between one or more devices / apparatuses mentioned in the present invention does not exclude the existence of other devices / apparatuses before or after the combination device / apparatus or the insertion of other devices / apparatuses between these explicitly mentioned two devices / apparatuses, unless otherwise specified. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or the scope of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the present invention without substantially changing the technical content.

[0038] Example 1 like Figure 1As shown, Example 1 of the present application provides a system for preserving human body fluids and excrement, including a sample box body 1, a sample carrier 2 for carrying samples arranged in the sample box body, and a sealing cover 13. The inner wall of the sample box body is provided with a carrier support net 4, and the sample carrier is fixed at the center of the carrier support net so that the sample carrier is non-contacting with the inner wall of the sample box body to ensure good air permeability. The sample carrier separates the internal space of the sample box body into a sample area 11 and a drying area 12. A first air permeable filter net 3 is provided below the sample carrier, and the first air permeable filter net is fixed to the inner wall of the sample box body and is located in the drying area. The carrier support net is arranged above the first air permeable filter net. The drying area is filled with a first desiccant 121, and the first desiccant is non-contacting with the sample carrier. The sample carrier has water absorption and air permeability. The sample box body and the sealing cover are sealed and fixed to form a sealing structure. The first desiccant uses chemical desiccant calcium oxide, and the sample carrier uses industrial wool felt with a thickness of 2 mm.

[0039] Example 2 like Figure 2 As shown, embodiment 1 of the present application provides a system for preserving human body fluids and excrement, comprising a sample box body 1, a sample carrier 2 for carrying samples arranged in the sample box body, and a sealing cover 13. A filling tube 14 having a hollow hole structure is arranged at the bottom of the sealing cover. The filling tube is filled with a second desiccant 141, and the second desiccant is in non-contact with the sample carrier. A carrier support net 4 is arranged on the inner wall of the sample box body, and the sample carrier is fixed at the center of the carrier support net so that the sample carrier is in non-contact with the inner wall of the sample box body to ensure good air permeability. The sample carrier separates the internal space of the sample box body into a sample area 11 and a drying area 12. A first air permeable filter net 3 is arranged below the sample carrier, and the first air permeable filter net is fixed to the inner wall of the sample box body and is located in the drying area. The carrier support net is arranged above the first air permeable filter net. The drying area is filled with a first desiccant 121, and the first desiccant is in non-contact with the sample carrier. The sample carrier has water absorption and air permeability. The sample box body and the sealing cover are sealed and fixed to form a sealing structure. The first desiccant is a chemical desiccant calcium oxide, and the second desiccant is a mixture of a chemical desiccant calcium oxide and a physical desiccant activated alumina. The sample carrier is an industrial wool felt with a thickness of 2 mm, which is cut into a square of 8 mm×8 mm when used.

[0040] Example 3 The difference between Example 3 and Example 1 is that the first desiccant is of a different type, specifically a physical oxidant activated alumina.

[0041] Comparative Examples 1 to 5 The difference between Comparative Examples 1 to 5 and Example 1 is that the sample carriers are different, as shown in Table 1.

[0042] Comparative Examples 6-10 The difference between Comparative Examples 6 to 10 and Example 1 is that the sample carriers are different and the types of the first desiccant are different. The sample carriers are specifically shown in Table 1, and the first desiccant uses a physical oxidant, activated alumina.

[0043] The present application also provides a method for preserving human body fluids and excrement using the preservation system of the above embodiments and comparative examples. The sample box body adopts a 50 mL medical centrifuge tube, the sealing cover adopts a centrifuge tube cover, and the types of the sample carrier and the first desiccant are detailed in Table 1. The preservation method comprises the following steps: Cut the sample carrier into a square of about 8 mm × 8 mm with scissors, fix it in the center of the carrier support net, add the first desiccant to the drying area; add the first desiccant to the 50 mL medical centrifuge tube, to the vicinity of 35 mL of the centrifuge tube, take 4 0.5 mL centrifuge tubes, cover them with tube caps and insert them upright into the first desiccant, and place the cut square sample carrier on the caps of the 4 0.5 mL centrifuge tubes. Tighten the 50 mL centrifuge tube caps and stick sealing tape on the tube mouths; Dry the sample carrier: The sample carrier and the first desiccant are subjected to gas exchange in the centrifuge tube for 24 hours. Simulated sample hemoglobin solution preparation: Human hemoglobin standard was dissolved in nuclease-free water and diluted with 10 mg / mL BSA (bovine serum albumin) solution to a final hemoglobin concentration of 10 ug / mL.

[0044] 50 μL of simulated sample was respectively taken with a 200 μL pipette and added to the middle of the sample carrier of the storage system of each embodiment and comparative example, and the sealing cover was tightened. The samples were divided into two groups, one group was stored in a 25°C incubator, and the other group was stored in a 37°C incubator.

[0045] Take out a sample on the 1st, 2nd and 3rd day respectively, take out one of the sample carriers, transfer it to a 2 mL centrifuge tube, add 2 mL of nuclease-free water, vortex for 30 seconds, let it stand at room temperature for 10 minutes, and vortex again for 30 seconds; take 100 μL of sample, add it to the immunofluorescence reagent card, and use the fully automatic immunofluorescence instrument to detect the hemoglobin content. The original hemoglobin sample was diluted about 40 times, and the final concentration was 250 ng / mL. Record the test values ​​for each day in ng / mL. The results are shown in Table 1: Table 1. Test results of simulated samples using the storage systems of Examples 1, 3 and Comparative Examples 1 to 10 at different storage temperatures It can be seen from Table 1 that the sample carrier with the best stability and elution effect is industrial wool felt, while other carriers have poor stability and elution comprehensive performance. The most preferred sample carrier is industrial wool felt.

[0046] As a physical desiccant, activated alumina absorbs water reversibly, which makes it impossible to completely dry the sample. The small amount of residual water makes the sample unstable. As a chemical desiccant, calcium oxide absorbs water irreversibly. It can completely and thoroughly absorb the water in the sealed container within a sufficient period of time, allowing the sample to be completely and thoroughly dehydrated, thereby achieving a stable effect. The first desiccant is most preferably calcium oxide; Comparing the differences between different storage temperatures of 25℃ and 37℃, at 25℃, calcium oxide as the first desiccant and industrial wool felt as the sample carrier had good stability; but at 37℃, the hemoglobin of this combination degraded by 40% on the first day, while it was stable on the second and third days compared to the first day, indicating that after the sample was added to the sample carrier, it was instantly absorbed and dried, but the drying was not thorough, and the stability was poor at high temperature, which needs further optimization.

[0047] In order to improve the stability of the samples at 37°C, the samples were stored in the human body fluid and excrement storage system of Example 1. After adding the samples, they were divided into two groups. The experimental group 1 was first placed at room temperature of 25°C for 24 hours, and then the 37°C experiment was performed; the control group 1 was directly stored at 37°C, and then the experimental group and the control group were tested using the same test method as above. The results are shown in Table 2: Table 2. Test results of different drying methods and different storage times at 37°C in experimental group 1 and control group 1 It can be seen from Table 2 that after adding the sample, drying it under relatively mild conditions (within 25°C) for 24 hours can significantly improve the stability of the sample at subsequent high temperatures.

[0048] In order to improve the stability of the sample before it is completely dehydrated in the storage system of Example 1, the present invention provides a sample buffer solution with a BSA (bovine serum albumin) solution as a core component, and this setting has an auxiliary effect.

[0049] Sample carrier preparation: Cut the industrial wool felt into squares of about 8 mm × 8 mm using scissors.

[0050] Design of desiccant container: Add granular calcium oxide to a 50 mL medical centrifuge tube until the tube reaches 35 mL. Take four 0.5 mL centrifuge tubes, cover them with caps and insert them upright into the calcium oxide. Place the cut square sample carriers on the caps of the four 0.5 mL centrifuge tubes. Tighten the caps of the 50 mL centrifuge tubes and apply sealing tape to the tube openings.

[0051] Drying the sample carrier: The sample carrier and calcium oxide are subjected to gas exchange in the centrifuge tube for 24 hours until the sample carrier and calcium oxide are subjected to gas exchange.

[0052] Hemoglobin solution preparation: Human hemoglobin standard was divided into 2 groups. Experimental group 2 was dissolved in nuclease-free water and diluted with 50 mg / mL BSA (bovine serum albumin) solution. The final hemoglobin concentration was 10 ug / mL. Control group 2 was diluted with nuclease-free water. The final hemoglobin concentration was 10 ug / mL. For each of the two groups of simulated samples, 50 μL of simulated sample was taken with a 200 μL pipette, added to the middle of the sample carrier, the centrifuge tube cap was tightened, and the tube mouth was sealed with sealing tape. Store at room temperature 25°C.

[0053] After 24 hours, take a sample from each group, remove the sample carrier, transfer to a 2 mL centrifuge tube, add 2 mL of nuclease-free water, vortex for 30 seconds, let stand at room temperature for 10 minutes, and vortex again for 30 seconds. Take 100 μL of sample, add to the immunofluorescence reagent card, and use an automatic immunofluorescence instrument to detect the hemoglobin content. The original hemoglobin sample was diluted about 40 times, and the final concentration was 250 ng / mL. Record the value.

[0054] The samples were divided into three groups and stored in incubators at 25°C, 37°C, and 65°C respectively.

[0055] Take a sample from each group on the 1st, 2nd, and 3rd day, remove the sample carrier, transfer to a 2 mL centrifuge tube, add 2 mL of nuclease-free water, vortex for 30 seconds, let stand at room temperature for 10 minutes, and vortex again for 30 seconds. Take 100 μL of sample, add it to the immunofluorescence reagent card, and use an automatic immunofluorescence instrument to detect the hemoglobin content. Record the test values ​​for each day in ng / mL. The results are shown in Table 3: Table 3. Test results of experimental group 2 and control group 2 at different temperatures and different storage times It can be seen from Table 3 that: from the comparison of the results at 25°C and 37°C, whether or not to add a protective buffer has no significant effect on stability; compared with the results at 65°C, when the protective buffer is added, the sample remains about 75%, while the sample without the protective buffer remains about 55%; the protective buffer does not significantly improve the stability under mild conditions (within 37°C), but can significantly improve the stability of the sample under relatively severe conditions.

[0056] Application Example 1: Study on the stability of hemoglobin in simulated human fecal samples Sample carrier preparation: Select industrial wool felt with a thickness of 2 mm and cut it into squares of about 8 mm × 8 mm with scissors.

[0057] Design of desiccant container: Add granular calcium oxide to a 50 mL medical centrifuge tube until the tube is about 35 mL. Take four 0.5 mL centrifuge tubes, cover them with caps and insert them upright into the calcium oxide. Place the cut square sample carriers on the caps of the four 0.5 mL centrifuge tubes. As an alternative to the breathable filter, it can ensure that the sample carrier and the calcium oxide below will not come into contact, but sufficient gas exchange can be achieved. Tighten the cap of the 50 mL centrifuge tube and apply sealing tape to the tube mouth.

[0058] Drying the sample carrier: The sample carrier and calcium oxide are subjected to gas exchange in a centrifuge tube for 24 hours, and the residual water in the sample carrier reacts chemically with the calcium oxide to completely dehydrate it.

[0059] Hemoglobin solution preparation: Human hemoglobin standard was dissolved in nuclease-free water and diluted with 50 mg / mL BSA (bovine serum albumin) solution to a final hemoglobin concentration of 10 ug / mL.

[0060] Simulated sample preparation: simulate the process of sampling and preparing stool samples before routine fecal occult blood testing. Take a small amount of human stool sample, about 0.2 grams of stool sample, add it to 10 mL of the above prepared hemoglobin solution, and shake to mix.

[0061] Use a 200 μL pipette to draw 50 μL of the simulated sample, add it to the middle of the sample carrier, tighten the centrifuge tube cap, and let it stand at room temperature. Prepare 20 identical samples in total.

[0062] After 1 hour, when the sample on the carrier is completely dry, remove one of the sample carriers, transfer it to a 2 mL centrifuge tube, add 2 mL of nuclease-free water, vortex for 30 seconds, let it stand at room temperature for 10 minutes, and vortex again for 30 seconds. Take 100 μL of sample, add it to the immunofluorescence reagent card, use the fully automatic immunofluorescence instrument to detect the hemoglobin content, and record the value as the control day, value T.

[0063] The mouths of the remaining sample centrifuge tubes were sealed with sealing tape and stored at room temperature.

[0064] After 24 hours, one of the samples was taken out, the sample carrier was removed, and it was transferred to a 2 mL centrifuge tube. 2 mL of nuclease-free water was added, vortexed for 30 seconds, left to stand at room temperature for 10 minutes, and vortexed again for 30 seconds. 100 μL of the sample was taken and added to the immunofluorescence reagent card. The hemoglobin content was detected using an automatic immunofluorescence instrument, and the value was recorded as the experimental day 0, value T0. The results are shown in Table 4.

[0065] The remaining 18 samples were divided into 3 groups, group 1 was stored in a 25-degree incubator, group 2 was stored in a 37-degree incubator, and group 3 was stored in a 65-degree incubator.

[0066] A sample was taken out on the 1st, 4th, 6th, 8th, 11th and 13th day respectively, and the hemoglobin concentration was tested according to the method in step 9. The values ​​were recorded as follows: the samples stored at 25 degrees were recorded as 25T1, 25T4, 25T6... The number after T represents the number of days the sample was stored; the samples stored at 37 degrees were recorded as 37T1, 37T4, 37T6... The number after T represents the number of days the sample was stored.

[0067] Taking the control day value T as the standard, the hemoglobin content on other days was divided by T to obtain the percentage of remaining hemoglobin. A line graph was made based on the percentage to analyze the sample stability. The results are as follows: Figure 3 shown.

[0068] Table 4. Test results of stability test of simulated fecal samples From Table 4 and Figure 3 It can be seen that, excluding the error of immunofluorescence itself, T0 is about 100% of T, indicating that the sample stability is good during room temperature drying; excluding the error of immunofluorescence itself, the hemoglobin concentration of the 25°C and 37°C samples is close to 100% compared with the control day T within 13 days, indicating that according to the method of the present invention, the hemoglobin in the fecal sample is stable. At 65°C, about 70% of the hemoglobin remains after degradation on the first day, but it can remain stable afterwards. This shows that under relatively extreme conditions, trace residual moisture still affects the stability of the sample; but after complete dehydration, a stable effect can be achieved.

[0069] Application Example 2: Hemoglobin stability experiment of simulated human urine sample Sample carrier preparation: Select industrial wool felt with a thickness of 2 mm and cut it into squares of about 8 mm × 8 mm with scissors.

[0070] Desiccant container design: Add granular calcium oxide to a 50 mL medical centrifuge tube until the tube is about 25 mL, and continue to add activated alumina until the tube is about 25 mL. Take 4 0.5 mL centrifuge tubes, cover them with tube caps and insert them upright into the activated alumina. Place the cut square sample carriers on the caps of the 4 0.5 mL centrifuge tubes. As an alternative to the breathable filter, it can ensure that the sample carrier and the activated alumina below will not come into contact, but gas exchange can be fully carried out. Tighten the 50 mL centrifuge tube cap and stick sealing tape on the tube mouth.

[0071] Dry sample carrier: The sample carrier and two desiccants are subjected to gas exchange in a centrifuge tube for 24 hours until the residual moisture in the sample carrier reacts chemically with calcium oxide and is completely dehydrated. The large surface area of ​​activated alumina can accelerate gas exchange.

[0072] Hemoglobin solution preparation: Human hemoglobin standard, dissolved in nuclease-free water, the final hemoglobin concentration is 200 ug / mL.

[0073] Simulated sample preparation: Take 18 mL of fresh urine, add 1 mL of hemoglobin stock solution, the final hemoglobin concentration is 10ug / mL, 1 gram of BSA (bovine serum albumin), and shake to mix. The final hemoglobin concentration is about 10 ug / mL, and the BSA (bovine serum albumin) concentration is about 50mg / mL.

[0074] Use a 200 μL pipette to draw 50 μL of the simulated sample, add it to the middle of the sample carrier, tighten the centrifuge tube cap, and let it stand at room temperature. Prepare 20 identical samples in total.

[0075] After 1 hour, when the sample on the carrier is completely dry, remove one of the sample carriers, transfer it to a 2 mL centrifuge tube, add 2 mL of nuclease-free water, vortex for 30 seconds, let it stand at room temperature for 10 minutes, and vortex again for 30 seconds. Take 100 μL of sample, add it to the immunofluorescence reagent card, use the fully automatic immunofluorescence instrument to detect the hemoglobin content, and record the value as the control day, value T.

[0076] The mouths of the remaining sample centrifuge tubes were sealed with sealing tape and stored at room temperature.

[0077] One day later, one of the samples was taken out, the sample carrier was removed, and it was transferred to a 2 mL centrifuge tube. 2 mL of nuclease-free water was added, vortexed for 30 seconds, left to stand at room temperature for 10 minutes, and vortexed again for 30 seconds. 100 μL of the sample was taken and added to the immunofluorescence reagent card. The hemoglobin content was detected using an automatic immunofluorescence instrument, and the value was recorded as the experimental day 0, value T0. The results are shown in Table 5.

[0078] The remaining 18 samples were divided into two groups, one group was stored in a 25-degree incubator and the other group was stored in a 37-degree incubator.

[0079] A sample was taken out on the 1st, 4th, 6th, 8th, 11th and 13th day respectively, and the hemoglobin concentration was tested according to the method in step 9. The values ​​were recorded as follows: the samples stored at 25 degrees were recorded as 25T1, 25T4, 25T6... The number after T represents the number of days the sample was stored; the samples stored at 37 degrees were recorded as 37T1, 37T4, 37T6... The number after T represents the number of days the sample was stored.

[0080] Taking the control day value T as the standard, the hemoglobin content on other days was divided by T to obtain the percentage of remaining hemoglobin. A line graph was made based on the percentage to analyze the sample stability. The results are as follows: Figure 4 shown.

[0081] Table 5. Test results of simulated urine sample stability experiment From Table 5 and Figure 4 It can be seen that, excluding the error of immunofluorescence itself, T0 is about 100% of T, indicating that the sample stability is good during room temperature drying; excluding the error of immunofluorescence itself, the hemoglobin concentration of 25℃ and 37℃ samples is close to 100% compared with the control day T within 13 days, indicating that according to the method of the present invention, the hemoglobin in the urine sample is stable. At 65℃, about 70% of hemoglobin remains after degradation on the first day, but it can remain stable afterwards. It shows that under relatively extreme conditions, trace residual moisture still affects the stability of the sample; but after complete dehydration, a stable effect can be achieved.

[0082] The stabilization method of the present invention is aimed at human body fluids and excrement samples, including proteins, carbohydrates, lipids, nucleic acids, and human metabolic waste, etc.; it also includes protein and nucleic acid components of microorganisms such as bacteria, fungi, and mycoplasma. Since hemoglobin is recognized as one of the components with the worst stability, hemoglobin is taken as an example in the application example. According to the design concept of the present invention, when all the above components are completely dehydrated, all enzymes lose their activity and cannot degrade proteins and nucleic acids; all microorganisms stop growing and reproducing, and cannot produce metabolic waste and change the content in the original sample. This means that all the information of the original sample is truly and accurately preserved, and the samples used in subsequent clinical tests can truly reflect the actual situation of the patient.

[0083] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for improving the storage stability of human body fluids and excrement, characterized in that: The human body fluid and / or excrement samples are firstly dehydrated quickly and then completely dehydrated to achieve stable storage of the human body fluid and / or excrement samples.

2. A system for preserving human body fluids and excrement, characterized in that: The sample box comprises a sample box body (1), wherein a sample carrier (2) for carrying a sample is arranged inside the sample box body, wherein the sample carrier divides the internal space of the sample box body into a sample area (11) and a drying area (12), wherein the drying area is filled with a first desiccant (121), wherein the first desiccant is in non-contact with the sample carrier, the sample carrier has water absorption and air permeability, and the sample box body has a sealing structure.

3. The storage system according to claim 2, characterized in that: A first air permeable filter (3) is provided below the sample carrier, and the first air permeable filter is fixed to the inner wall of the sample box body.

4. The storage system according to claim 3, characterized in that: The inner wall of the sample box body also includes a carrier support net (4) arranged above the first air permeable filter net, the sample carrier is fixed at the center of the carrier support net, and the sample carrier is non-contacting with the inner wall of the sample box body.

5. The storage system according to claim 2, characterized in that: The sample box body is provided with a sealing cover (13), the bottom of the sealing cover is provided with a filling tube (14) having a hollow hole structure, the filling tube is filled with a second desiccant (141), and the second desiccant is in non-contact with the sample carrier.

6. The storage system according to claim 5, characterized in that: A second air-permeable filter is provided between the filling tube and the sample carrier.

7. The storage system according to claim 5, characterized in that: At least one of the first desiccant and the second desiccant reacts irreversibly with water molecules; the material of the sample carrier is cellulose or animal hair.

8. A method for preserving human body fluids and excrement, characterized in that: Using the human body fluid and excrement preservation system as described in any one of claims 2 to 7, placing the human body fluid or excrement sample on the surface of the sample carrier and sealing the sample box body;.

9. The storage method according to claim 8, characterized in that: When the storage environment temperature is greater than 37°C, the method further includes a sample pretreatment step of adding a buffer to the human body fluid or excrement sample, wherein the buffer contains a protein protective agent selected from one or more of bovine serum albumin, trehalose, heme and a protease inhibitor.

10. Use of the human body fluid and excrement storage system as claimed in any one of claims 2 to 7 in medical testing.

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