Sample treating fluid and kit for novel coronavirus antigen detection

Abstract

The invention discloses a sample treatment solution and a kit for novel coronavirus antigen detection, the sample treatment solution comprises a biological buffer solution, animal protein and a surfactant, the biological buffer solution comprises a sodium hydroxide solution of glycine, and the surfactant comprises perfluorooctanoic acid. According to the sample treatment liquid, the biological buffer solution of the sodium hydroxide solution containing glycine is adopted, animal serum is used as a protective agent, and the surfactant containing perfluorooctanoic acid is matched, so that the long-time normal-temperature storage stability and the cryopreservation stability of the novel coronavirus antigen N protein in the sample treatment liquid can be effectively improved, and the sample treatment liquid has the advantages that the sample treatment liquid is safe and reliable. The novel coronavirus antigen N protein is prevented from being degraded, the problem that monitoring must be carried out immediately after a sample is collected is solved, and the detection accuracy, sensitivity and anti-interference capability of delayed detection are improved.

Description

Technical Field

[0001] The present application relates to the field of biological detection technology, and in particular to a sample processing liquid and a kit for novel coronavirus antigen detection. Background Art

[0002] The new coronavirus (2019-nCoV) belongs to the β coronavirus family. It is sensitive to ultraviolet rays and heat. Ether, 75% ethanol, chlorine-containing disinfectants, peracetic acid, chloroform and other lipid solvents can effectively inactivate the virus. However, the general population is susceptible, and the main source of infection is people infected with the new coronavirus. The main transmission routes include respiratory droplets and close contact. It is also easy to spread through aerosols in a relatively closed environment. Infection may also occur after contact with objects contaminated by the virus.

[0003] Since the outbreak of the novel coronavirus infection, my country's epidemic prevention and control has successfully avoided the widespread spread of relatively pathogenic original strains and delta variants, greatly reducing severe illness and death; currently, with the virus mutation, epidemic changes, vaccination popularization and accumulation of prevention and control experience, my country's novel coronavirus infection prevention and control is facing new situations and new tasks, and prevention and control work has entered a new stage; judging from the virus mutation, domestic and foreign experts generally believe that the general direction of virus mutation is lower pathogenicity, more prone to upper respiratory tract infection and shorter incubation period. The new coronavirus will exist in nature for a long time, and its pathogenicity will be significantly lower than in the early stage, and the disease caused will gradually evolve into a common respiratory infectious disease.

[0004] At present, the Omicron variant is the dominant strain prevalent at home and abroad. It has a shortened incubation period of mostly 2-4 days, stronger transmission ability, faster transmission speed, weakened pathogenicity, and stronger immune escape ability. Although the number of infected people is large, asymptomatic infections and mild cases account for more than 90%, and the severity and mortality rates are extremely low.

[0005] A positive nucleic acid test is the gold standard for detecting novel coronavirus carriers (positive novel coronavirus nucleic acid but no obvious clinical and imaging manifestations, and negative serum-specific novel coronavirus antibodies) and confirming 2019-nCoV infection. However, in epidemic areas, fever clinics and emergency departments often face a large number of symptomatic suspected patients, and rapid differential diagnosis and diversion management are urgently needed. Especially for primary medical institutions that do not have the conditions to quickly carry out novel coronavirus nucleic acid testing, rapid antigen testing can be used as a beneficial supplement to nucleic acid testing, so as to quickly screen and control positive cases in a shorter time, thereby reducing the risk of further spread of the virus in crowded medical places.

[0006] However, the following problems often occur when using the colloidal gold method or latex method to detect novel coronavirus antigens:

[0007] 1) Since the sample treatment solution fails to provide good protection, the antigen is degraded, resulting in poor sensitivity of the detection kit;

[0008] 2) Antigen testing requires that samples are immersed in sample processing fluid after collection. The samples have poor stability in the processing fluid and are difficult to preserve for a long time. If the samples are not tested in time after sampling, false negative results may occur, reducing the accuracy of the test;

[0009] 3) When samples are immersed in sample processing solution and stored at low temperatures, the antigen content will be significantly reduced, which may also cause inaccurate detection. Summary of the invention

[0010] In view of the problems existing in the above-mentioned prior art, the present application provides a sample processing solution and a kit for novel coronavirus antigen detection; the technical solution is as follows:

[0011] The present application provides a sample processing liquid for novel coronavirus antigen detection, comprising a biological buffer, animal protein and a surfactant, wherein the biological buffer comprises a sodium hydroxide solution of glycine, and the surfactant comprises perfluorooctanoic acid.

[0012] Furthermore, the concentration of glycine in the sample processing solution is 0.1M-0.5M.

[0013] Furthermore, the pH of the biological buffer is 8.0-11.0.

[0014] Furthermore, the concentration of the surfactant in the sample processing liquid is 0.5 g / L to 1.5 g / L.

[0015] Furthermore, the animal serum includes special grade newborn calf serum.

[0016] Furthermore, the concentration of the special-grade newborn calf serum in the sample processing solution is 10 g / L to 20 g / L.

[0017] Furthermore, the sample processing liquid also includes a biological preservative, and the biological preservative includes 2-methyl-4-isothiazoline-3-one hydrochloride.

[0018] Furthermore, the concentration of the biological preservative in the sample processing liquid is 3 g / L to 6 g / L.

[0019] Furthermore, the sample processing liquid is used to process at least one of nasal swabs, nasopharyngeal swabs and oropharyngeal swabs. During the processing of a single sample, the amount of the sample processing liquid used is 300 μL to 600 μL.

[0020] On the other hand, the present application also provides a kit comprising a sample processing liquid for novel coronavirus antigen detection as described in any of the above items.

[0021] Implementing this application has the following beneficial effects:

[0022] 1. The sample processing liquid of the present application adopts a biological buffer solution including a sodium hydroxide solution of glycine, uses animal serum as a protective agent, and cooperates with a surfactant including perfluorooctanoic acid, which can effectively improve the stability of the new coronavirus antigen N protein in the sample processing liquid for a long time, and the animal serum can effectively avoid the nonspecific adsorption of the antibody when recognizing the N protein, prevent the degradation of the new coronavirus antigen N protein, solve the problem that monitoring must be carried out immediately after sample collection, and is conducive to improving the detection accuracy, sensitivity and anti-interference ability of delayed detection; at the same time, the sodium hydroxide solution of glycine and perfluorooctanoic acid work together to effectively lower the freezing point of the sample processing liquid, so that the new coronavirus antigen N protein can be frozen and stored in the sample processing liquid, improve the stability of N protein after multiple freeze-thaw storage, and also help to improve the detection sensitivity; in addition, perfluorooctanoic acid as a surfactant can also be beneficial to the upward speed of the sample on the test strip, shorten the detection time of the new coronavirus antigen detection using the colloidal gold method or latex method, and improve the detection efficiency.

[0023] 2. The biological preservatives used in this application include 2-methyl-4-isothiazoline-3-one hydrochloride, which can effectively inhibit bacterial growth and prevent contamination, further enhance the protective effect of the sample treatment fluid on the new coronavirus antigen N protein in the sample, and prolong the room temperature storage time and frozen insulation time of the new coronavirus antigen N protein, which is conducive to further improving the detection accuracy and reliability. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments, and therefore cannot be understood as limiting the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0025] It should be noted that in the description of the present application, for the following defined terms, unless a different definition is given in the claims or elsewhere in this specification, these definitions should be applied. All numerical values, whether or not explicitly indicated, are defined herein as being modified by the term "about". The term "about" generally refers to a numerical range that a person of ordinary skill in the art would consider to be equivalent to the stated value to produce substantially the same properties, functions, results, etc. A numerical range indicated by a low value and a high value is defined to include all numerical values ​​included in the numerical range and all subranges included in the numerical range.

[0026] It should be noted that the terms "first", "second" etc. in the specification and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the objects used in this way can be interchanged in appropriate circumstances, so that the embodiments of the present application can be implemented in the order except for the following description. In addition, the terms "comprise" and "have" and any of their variations are intended to cover non-exclusive inclusions, for example, the process, method, system, product comprising a series of steps or units need not be limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, or products.

[0027] In the prior art, it is difficult to maintain the stability of the novel coronavirus antigen N protein in the sample for a long time in the treatment of the novel coronavirus antigen N protein in the sample for the novel coronavirus antigen detection, and the stability of the frozen storage is also poor, which is difficult to meet the needs of multiple repeated freeze-thaw detection, resulting in decreased detection accuracy, insufficient sensitivity and other problems; based on this, the embodiment of the present application provides a sample processing liquid for novel coronavirus antigen detection, including a biological buffer, an animal protein and a surfactant, the biological buffer includes a sodium hydroxide solution of glycine, and the surfactant includes perfluorooctanoic acid; the novel coronavirus antigen detection adopts a colloidal gold method or a latex method for detection, wherein the animal serum is used as a protective agent to effectively improve the stability of the N protein in the sample processing liquid, prevent the degradation of the N protein, and effectively solve the nonspecific adsorption when the antibody recognizes the N protein; the sodium hydroxide solution of glycine and the perfluorooctanoic acid are combined to effectively reduce the freezing point of the sample processing liquid, and can improve the sample processing liquid to play a role in cryopreservation of the N protein, taking into account the improvement of the room temperature storage stability and the frozen storage stability of the N protein for a long time, and at the same time, it is beneficial to improve the detection sensitivity, and can also promote the speed of the sample on the test strip, shorten the detection time, and improve the detection efficiency.

[0028] Specifically, the concentration of glycine in the sample processing solution is 0.1M~0.5M; it can be understood that the concentration of glycine in the sample processing solution can be any point value in the range of 0.1M~0.5M; illustratively, the concentration of glycine in the sample processing solution can be 0.1M, 0.15M, 0.2M, 0.25M, 0.3M, 0.35M, 0.4M, 0.45M, 0.5M, etc.; within this concentration range, glycine, as the main protective agent, can effectively maintain the stability of N protein in the sample processing solution, and glycine can also form a relatively stable formula structure after freeze-drying, preventing the N protein from structurally collapsing during the cryopreservation process, greatly improving the room temperature storage stability and cryopreservation stability of the N protein when the sample processing solution is used to treat the new coronavirus N protein; in addition, adding glycine to the sample processing solution is also beneficial to improving the detection sensitivity.

[0029] Specifically, sodium hydroxide is used to adjust the pH of the biological buffer and the sample processing liquid, and the added concentration of sodium hydroxide can be determined by the final required pH; in some exemplary embodiments, the pH of the biological buffer is 8.0-11.0, and in the final sample processing liquid, other added components, such as surfactants, etc., hardly affect the volume of the sample processing liquid, so that the volume of the biological buffer is almost the same as that of the sample processing liquid, and the solution pH of the sample processing liquid is maintained in this pH range, that is, the pH of the sample processing liquid is 8.0-11.0; it can be understood that the pH of the biological buffer can be any point value between 8.0 and 11.0; illustratively, the pH of the biological buffer can be 8.0, 8.5, 9.0, 9.5, 10.0, 10.5, 11.0, etc.; in this way, the final sample processing liquid can provide an alkaline environment, which is beneficial to the stability of the new coronavirus antigen N protein in an alkaline environment, is not easy to degrade or damage, improves the storage stability of the sample for new coronavirus antigen detection, and at the same time improves the detection sensitivity and anti-interference ability, and the sample processing liquid has good applicability in clinical treatment of new coronavirus antigens.

[0030] Specifically, the concentration of the surfactant in the sample processing liquid is 0.5g / L to 1.5g / L; it can be understood that the concentration of the surfactant in the sample processing liquid can be any point value in the range of 0.5g / L to 1.5g / L; illustratively, the concentration of the surfactant in the sample processing liquid can be 0.5g / L, 0.7g / L, 0.8g / L, 0.9g / L, 1.0g / L, 1.2g / L, 1.4g / L, 1.5g / L, etc.; thus, perfluorooctanoic acid as a surfactant is beneficial to enhance the sample of the new coronavirus antigen in the test strip. The upward speed is beneficial to shorten the detection time and improve the detection efficiency; more importantly, it can cooperate with the sodium hydroxide solution of glycine to effectively lower the freezing point of the sample processing liquid, avoid destroying the protein structure of the N protein during the freezing process, so as to improve the freezing storage stability of the sample processing liquid for the N protein, meet the needs of repeated freezing and thawing of samples for detection, and can be repeatedly frozen and thawed 4 times before re-detection with high detection accuracy, detection sensitivity and anti-interference; in some preferred embodiments, the concentration of the surfactant in the sample processing liquid is 0.8g / L~1.2g / L.

[0031] Specifically, the animal serum includes premium newborn calf serum, which is serum taken from the blood of calves within 14 hours of birth, obtained through aseptic collection, separation, and microporous filtration. It contains a variety of plasma proteins, polypeptides, fats, carbohydrates, growth factors, hormones, and inorganic substances, etc. It is rich in nutrients, has high protein content and various growth factors, and contains very few antibodies, complement, and other components that are harmful to cells and proteins. The premium newborn calf serum, as a protective agent, can effectively protect the N protein, prevent the decomposition of the N protein, and protect the N protein from the influence of external environmental factors, thereby greatly improving the stability of the N protein in the sample processing solution containing the premium newborn calf serum. At the same time, the premium newborn calf serum can effectively prevent the non-specific adsorption of antibodies when recognizing the N protein, which is further beneficial to the stability of the N protein in the sample processing solution for a long time.

[0032] Specifically, the concentration of premium newborn calf serum in the sample processing liquid is 10g / L to 20g / L; it can be understood that the concentration of premium newborn calf serum in the sample processing liquid can be any point value between 10g / L and 20g / L; illustratively, the concentration of premium newborn calf serum in the sample processing liquid is 10g / L, 12g / L, 15g / L, 16g / L, 17g / L, 17.5g / L, 18g / L, 19g / L, 20g / L, etc.; in this way, the premium newborn calf serum can effectively play a protective role and improve the long-term stability of N protein in the sample processing liquid; in some preferred embodiments, the concentration of premium newborn calf serum in the sample processing liquid is 15g / L to 20g / L.

[0033] Specifically, in some exemplary embodiments, the sample processing liquid also includes a biological preservative, and the biological preservative includes 2-methyl-4-isothiazoline-3-one hydrochloride (MIT). The sample processing liquid contains animal serum, which is easy to breed microorganisms at room temperature. The biological preservative can effectively inhibit the growth of bacteria in the sample processing liquid, maintain the stability of the environment in which the N protein is located in the sample processing liquid, prevent contamination, and further help to improve the storage stability of the N protein.

[0034] Specifically, the concentration of the biological preservative in the sample processing liquid is 3g / L to 6g / L; it can be understood that the concentration of the biological preservative in the sample processing liquid can be any point value between 3g / L and 6g / L; illustratively, the concentration of the biological preservative in the sample processing liquid can be 3g / L, 3.5g / L, 3.7g / L, 4g / L, 4.5g / L, 5g / L, 5.5g / L, 6g / L, etc.; in this way, the antibacterial effect is good, and the purity and stability of the sample processing liquid and the new coronavirus antigen N protein that is stored for a long time can be effectively maintained, which is beneficial to improve the subsequent detection accuracy, sensitivity and anti-interference ability for new coronavirus antigen detection; in some preferred embodiments, the concentration of the biological preservative in the sample processing liquid is 3g / L to 5g / L.

[0035] Specifically, the sample processing liquid is used to process at least one of nasal swabs, nasopharyngeal swabs and oropharyngeal swabs; illustratively, the sample processing liquid is used to process a nasal swab; further illustratively, the sample processing liquid is used to process an oropharyngeal swab; the sample processing liquid can be used to process a variety of samples and has a wide range of applications.

[0036] Specifically, in the process of processing a single sample, the amount of sample processing liquid used is 300μL~600μL; it can be understood that in the process of processing a single sample, the amount of sample processing liquid used can be any point value between 300μL and 600μL; exemplarily, in the process of processing a single sample, the amount of sample processing liquid used can be 300μL, 320μL, 350μL, 375μL, 400μL, 425μL, 450μL, 500μL, 550μL, 600μL, etc.; within this dosage range, on the one hand, the effectiveness of the sample processing liquid in maintaining the stability of N protein can be improved, and on the other hand, the waste of sample processing liquid can be avoided and costs can be saved; in some preferred embodiments, in the process of processing a single sample, the amount of sample processing liquid used is 350μL~450μL.

[0037] On the other hand, an embodiment of the present application also provides a kit, comprising a sample processing liquid for novel coronavirus antigen detection as described above, wherein the kit is used for novel coronavirus antigen detection, and the sample processing liquid is used to process novel coronavirus antigen samples, especially to maintain the stability of the N protein in the sample, so as to improve the specificity, sensitivity, detection accuracy and anti-interference of the novel coronavirus antigen detection process of the kit.

[0038] The special-grade newborn calf serum produced by Lanzhou Minhai Bioengineering Co., Ltd. is used. The technical solution of the present application is described in detail below in conjunction with specific embodiments.

[0039] Example 1

[0040] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special grade newborn calf serum, 1.0 g of perfluorooctanoic acid, 4 g of MIT and purified water were diluted to 1 L to obtain a sample treatment solution 1.

[0041] Example 2

[0042] 37.525 g (0.5 M) glycine, 10.2 mL 1 M sodium hydroxide, 20 g special grade newborn calf serum, 1.0 g perfluorooctanoic acid, 4 g MIT and purified water were diluted to 1 L to obtain sample treatment solution 2.

[0043] Example 3

[0044] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special grade newborn calf serum, 0.5 g of perfluorooctanoic acid, 4 g of MIT and purified water were diluted to 1 L to obtain sample treatment solution 3.

[0045] Example 4

[0046] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special grade newborn calf serum, 1.5 g of perfluorooctanoic acid, 4 g of MIT and purified water were diluted to 1 L to obtain sample treatment solution 4.

[0047] Example 5

[0048] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 15 g of special grade newborn calf serum, 1.0 g of perfluorooctanoic acid, 4 g of MIT and purified water were diluted to 1 L to obtain sample treatment solution 5.

[0049] Example 6

[0050] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 10 g of special grade newborn calf serum, 1.0 g of perfluorooctanoic acid, 4 g of MIT and purified water were diluted to 1 L to obtain sample treatment solution 6.

[0051] Example 7

[0052] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special grade newborn calf serum, 1.0 g of perfluorooctanoic acid, 3 g of MIT and purified water were diluted to 1 L to obtain sample treatment solution 7.

[0053] Example 8

[0054] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special grade newborn calf serum, 1.0 g of perfluorooctanoic acid, 5 g of MIT and purified water were diluted to 1 L to obtain a sample treatment solution 8.

[0055] Comparative Example 1

[0056] 3.75 g (0.05 M) glycine, 10.2 mL 1 M sodium hydroxide, 20 g special grade newborn calf serum, 1.0 g perfluorooctanoic acid, 4 g MIT and purified water were diluted to 1 L, and the pH was adjusted to 8.5 to obtain sample treatment solution 9.

[0057] Comparative Example 2

[0058] 60.04 g (0.8 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special grade newborn calf serum, 1.0 g of perfluorooctanoic acid, 4 g of MIT and purified water were diluted to 1 L to obtain a sample treatment solution 10.

[0059] Comparative Example 3

[0060] 20 g of special-grade newborn calf serum, 1.0 g of perfluorooctanoic acid, 4 g of MIT and purified water were diluted to 1 L to obtain a sample treatment solution 11.

[0061] Comparative Example 4

[0062] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special-grade newborn calf serum, 4 g of MIT and purified water were diluted to 1 L to obtain a sample treatment solution 12 .

[0063] Comparative Example 5

[0064] 15.01 g (0.2 M) glycine, 10.2 mL 1 M sodium hydroxide, 20 g special grade newborn calf serum, 0.2 g perfluorooctanoic acid, 4 g MIT and purified water were diluted to 1 L to obtain a sample treatment solution 13.

[0065] Comparative Example 6

[0066] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special grade newborn calf serum, 2.0 g of perfluorooctanoic acid, 4 g of MIT and purified water were diluted to 1 L to obtain a sample treatment solution 14.

[0067] Comparative Example 7

[0068] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 1.0 g of perfluorooctanoic acid, 4 g of MIT and purified water were added to a volume of 1 L to obtain a sample treatment solution 15 .

[0069] Comparative Example 8

[0070] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special grade newborn calf serum, 1.0 g of perfluorooctanoic acid, 1 mL of ProClin300 and purified water were diluted to 1 L to obtain a sample treatment solution 16.

[0071] Comparative Example 9

[0072] 15.01 g (0.2 M) glycine, 10.2 mL 1 M sodium hydroxide, 20 g special grade newborn calf serum, 1.0 g perfluorooctanoic acid, 1 mL ProClin950 and purified water were diluted to 1 L to obtain sample treatment solution 17.

[0073] Comparative Example 10

[0074] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special grade newborn calf serum, 1.0 g of perfluorooctanoic acid and purified water were diluted to 1 L to obtain a sample treatment solution 18.

[0075] Comparative Example 11

[0076] 15.01 g (0.2 M) glycine, 10.2 mL 1 M sodium hydroxide, 20 g special grade newborn calf serum, 1.0 g perfluorooctanoic acid, 1 g MIT and purified water were diluted to 1 L to obtain a sample treatment solution 19.

[0077] Comparative Example 12

[0078] 15.01 g (0.2 M) of glycine, 10.2 mL of 1 M sodium hydroxide, 20 g of special grade newborn calf serum, 1.0 g of perfluorooctanoic acid, 7 g of MIT and purified water were diluted to 1 L to obtain a sample treatment solution 20.

[0079] The sample processing liquids in the above-mentioned embodiments and comparative examples were used to process negative, weakly positive, and positive nasal swab and oropharyngeal swab samples, and their respective background conditions were examined to verify the various properties of the sample processing liquids provided in the embodiments of the present application.

[0080] First, according to Example 1-2 and Comparative Example 1-2, the detection ability of sodium hydroxide solutions with different concentrations of glycine on samples was verified, and the detection results are shown in Table 1 below.

[0081] Table 1 Detection ability of sodium hydroxide solution with different concentrations of glycine on samples

[0082]

[0083] As can be seen from Table 1, sample treatment solution 9 (0.05M glycine-sodium hydroxide) and sample treatment solution 10 (0.8M glycine-sodium hydroxide) themselves will interfere with the detection process, and a weak positive false positive effect will appear in the background. Sample treatment solution 1 (0.2M glycine-sodium hydroxide) and sample treatment solution 2 (0.5M glycine-sodium hydroxide) can both achieve better results, indicating that only when the glycine concentration in the sample treatment solution is in the range of 0.1M to 0.5M can the protective effect of the sample treatment solution on the N protein be effectively improved, and the stability of the N protein be improved.

[0084] Second, according to Examples 1, 3-4 and Comparative Examples 3-6, the differences in freeze-thaw stability of samples when sodium hydroxide solution of glycine and perfluorooctanoic acid were used alone and in combination were verified, wherein the test results for nasal swab samples are shown in Table 2 below, and the test results for oropharyngeal swabs are shown in Table 3 below.

[0085] Table 2 Effects of different combinations on freeze-thaw stability of nasal swab samples

[0086]

[0087]

[0088] Table 3 Effects of different combinations on freeze-thaw stability of oropharyngeal swab samples

[0089]

[0090] It can be seen from Tables 2 and 3 that no glycine sodium hydroxide solution was added to sample processing liquid 11, resulting in poor freeze-thaw stability of the sample relative to sample processing liquid 1; no perfluorooctanoic acid was added to sample processing liquid 12, resulting in the liquid not moving upward during the detection process and the detection failed; in sample processing liquids 13-14, the perfluorooctanoic acid concentration was outside the range of 0.5g / L~1.5g / L, and when the perfluorooctanoic acid concentration was lower than 0.2g / L or higher than 1.5g / L, the freeze-thaw stability of the sample would also deteriorate; while in sample processing liquids 1, 3-4, the glycine sodium hydroxide solution and 0.5g / L~1.5g / L perfluorooctanoic acid can effectively improve the stability of the new coronavirus antigen sample under repeated freeze-thaw conditions, and can still have good stability after repeated freeze-thaw cycles 4 times.

[0091] Third, according to Examples 1, 5-6 and Comparative Example 7, the effects of perfluorooctanoic acid alone and in combination with premium newborn calf serum on detection sensitivity were verified. Weakly positive nasal swab samples and samples were tested respectively, and the test results are shown in Table 4 below.

[0092] Table 4 Effects of perfluorooctanoic acid and premium newborn calf serum on detection sensitivity

[0093]

[0094]

[0095] As can be seen from Table 4, the sample processing liquid 15 lacks premium newborn calf serum, resulting in the sensitivity not meeting the detection requirements. However, the perfluorooctanoic acid and premium newborn calf serum in the sample processing liquids 1, 5-6 synergize with each other, have a good detection effect on weak positive samples, and have high detection sensitivity.

[0096] Fourth, according to Example 1 and Comparative Example 7, the effects of sodium hydroxide solution of glycine on room temperature stability when used alone and in combination with premium newborn calf serum were verified. The moderately positive, weakly positive, and negative nasal swab and oropharyngeal swab samples were tested respectively. The test results are shown in Tables 5 and 6 below.

[0097] Table 5 Effect of newborn calf serum on room temperature stability of nasal swab samples

[0098]

[0099] Table 6 Effect of newborn calf serum on room temperature stability of oropharyngeal swab samples

[0100]

[0101] It can be seen from Tables 5 and 6 that in the sample treatment solution containing glycine sodium hydroxide solution but not including premium newborn calf serum, the new coronavirus antigen N protein has begun to degrade after 2 hours at room temperature; and when the glycine sodium hydroxide solution is added with premium newborn calf serum, the sample treatment solution can effectively prevent the degradation of N protein, and the test results of the sample will not be affected by the sampling time problem within 48 hours at room temperature, and the storage time of the sample is greatly extended.

[0102] Fifth, according to Example 1 and Comparative Examples 8-9, the antibacterial property of MIT was verified. Among them, Comparative Examples 8-9 respectively used different preservatives ProClin300 and ProClin950, and then placed in a 37°C constant temperature incubator to simulate the bacterial growth of the sample treatment liquid under an extreme environment. The bacterial growth was mainly judged by observing whether the solution became turbid. The test results are shown in Table 7 below.

[0103] Table 7 Effects of different biological preservatives on sample treatment fluid

[0104]

[0105] As shown in Table 7, the sample processing solutions prepared by ProClin300, ProClin950 and MIT can all be maintained at 37°C extreme environment for 48 hours. In comparison, the sample processing solution including MIT can be maintained at 37°C extreme environment for up to 60 hours, which can better maintain the relative stability time of the sample processing solution.

[0106] Further, according to Examples 1, 7-8 and Comparative Examples 10-12, the effects of different concentrations of biological preservatives on the stability of the sample treatment solution were verified. The sample treatment solution was placed in a 37°C constant temperature incubator to simulate the bacterial growth of the sample treatment solution under an extreme environment. The bacterial growth was mainly determined by observing whether the solution became turbid. The test results are shown in Table 8 below.

[0107] Table 8 Effects of different biopreservative concentrations on sample treatment fluid

[0108]

[0109] As shown in Table 8, without adding biological preservatives, turbidity appeared in the sample treatment solution after 24 hours; when the MIT concentration was 3g / L~5g / L, the clear state could be maintained for up to 60 hours, but below or above this concentration range, the antibacterial effect may be significantly reduced.

[0110] Sixth, using the sample processing solution in Example 1, three positive samples were diluted to weak positive with the sample processing solution, and each sample was tested 20 times to detect the effect of the sample processing solution on the minimum detection limit. The test results are shown in Table 9 below; it can be seen that the sample processing solution also has good detection ability for weak positive samples and has high detection sensitivity.

[0111] Table 9 Minimum detection limit

[0112] Sample No. Positive Detection rate CLR901-20 20 / 20 100％ CLR901-21 20 / 20 100％ CLR901-22 20 / 20 100％

[0113] Seventh, using the sample treatment solution in Example 1, the pathogens were diluted to a cross-reaction test concentration of 1×10 6 CFU / mL, virus is 1×10 5 TCID 50 / mL or 1×10 6 The COVID-19 antigen detection kit was used for testing, and the test results are shown in Table 10 below. It can be seen that there is no cross-reaction when the sample treatment fluid is used to treat common pathogens.

[0114] Table 10 Cross-reaction

[0115]

[0116]

[0117] Eighth, the sample treatment solution 1 in Example 1 was used to dilute the interfering substances to a certain concentration, and the anti-interference ability of the sample treatment solution with common interfering substances was verified. The test results are shown in Table 11 below; it can be seen that there is no cross reaction between the sample treatment solution and common interfering substances after treatment.

[0118] Table 11 Anti-interference capability

[0119]

[0120]

[0121] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0122] What is described above are only some embodiments of the present application and are not intended to limit the present application. Those skilled in the art should understand that the present application may undergo various changes and improvements, and any modifications, equivalent substitutions and improvements made in accordance with the present application shall fall within the scope of protection required by the present application.

Claims

1. A sample processing solution for novel coronavirus antigen detection, characterized in that: The invention comprises a biological buffer, animal protein and a surfactant. The biological buffer comprises a sodium hydroxide solution of glycine, and the surfactant comprises perfluorooctanoic acid.

2. The sample processing solution for novel coronavirus antigen detection according to claim 1, characterized in that: The concentration of glycine in the sample processing solution is 0.1M-0.5M.

3. The sample processing solution for novel coronavirus antigen detection according to claim 1, characterized in that: The pH of the biological buffer is 8.0-11.

0.

4. The sample processing solution for novel coronavirus antigen detection according to claim 1, characterized in that: The concentration of the surfactant in the sample processing solution is 0.5 g / L to 1.5 g / L.

5. The sample processing solution for novel coronavirus antigen detection according to claim 1, characterized in that: The animal serum includes special grade newborn calf serum.

6. The sample processing solution for novel coronavirus antigen detection according to claim 5, characterized in that: The concentration of the special-grade newborn calf serum in the sample processing solution is 10 g / L to 20 g / L.

7. The sample processing solution for novel coronavirus antigen detection according to any one of claims 1 to 6, characterized in that: The sample processing liquid also includes a biological preservative, and the biological preservative includes 2-methyl-4-isothiazoline-3-one hydrochloride.

8. The sample processing solution for novel coronavirus antigen detection according to claim 7, characterized in that: The concentration of the biological preservative in the sample processing liquid is 3 g / L to 6 g / L.

9. The sample processing solution for novel coronavirus antigen detection according to any one of claims 1 to 6, characterized in that: The sample processing liquid is used to process at least one of nasal swabs, nasopharyngeal swabs and oropharyngeal swabs. During the processing of a single sample, the amount of the sample processing liquid used is 300 μL to 600 μL.

10. A kit, characterized in that: Including a sample processing liquid for novel coronavirus antigen detection as described in any one of claims 1 to 9.

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