Nucleic acid scavenger
By using a mixture of nucleic acid removal solutions A and B, the problem of PCR technology being susceptible to nucleic acid contamination is solved, achieving efficient, safe, and convenient nucleic acid removal, reducing false positive results and equipment damage, and improving laboratory efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-24
- Publication Date
- 2026-04-14
AI Technical Summary
PCR technology is susceptible to nucleic acid contamination, leading to false positive results. Existing measures are complex, inefficient, and costly.
A nucleic acid removal agent is provided, comprising solution A and solution B. Solution A is an active oxygen source, and solution B is a synergistic ingredient. The agent is used by spraying or wiping to remove nucleic acid contamination. Solution A includes urea peroxide, polyvinylpyrrolidone, polyethylene glycol 4000 and buffer components, while solution B includes trehalose, glycerin, collagen peptides and horseradish peroxidase. The mixture is used to remove DNA and aerosol contamination.
It effectively disrupts DNA structure, reduces false positive results, simplifies operation, reduces equipment corrosion and costs, improves experimental accuracy and efficiency, and is safe and environmentally friendly.
Smart Images
Figure CN121852148A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of molecular biology experimental technology, and specifically to a nucleic acid scavenging agent. Background Technology
[0002] Polymerase chain reaction (PCR)-based nucleic acid amplification and detection technology is currently the most commonly used molecular experimental technique, widely applied in medical testing, biological experiments, and animal and plant quarantine. In the medical field, PCR technology is widely used for the detection and diagnosis of pathogens such as viruses, bacteria, and fungi. Through PCR, the presence of a pathogen in a patient can be detected quickly and accurately, providing doctors with accurate diagnostic information. Furthermore, PCR technology can be used for the diagnosis of hereditary diseases and prenatal genetic diagnosis, helping families understand the fetus's genetic status and preventing the occurrence of genetic diseases. In biological experiments, PCR technology is an important tool for studying gene expression, gene regulation, and genome structure. Through PCR, scientists can quickly obtain large amounts of DNA fragments for subsequent experimental operations. In addition, PCR technology can be used for gene cloning and gene library construction, facilitating research in genetic engineering. In the field of animal and plant quarantine, PCR technology also plays a crucial role. By conducting PCR testing on imported goods and items carried by passengers, the spread and invasion of harmful organisms can be detected and prevented in a timely manner, protecting my country's agricultural production and ecological security.
[0003] While the high sensitivity of PCR technology has greatly facilitated molecular biology research, it also presents a significant problem—susceptibility to nucleic acid contamination, leading to false positive results. This contamination can originate from multiple stages, including sample collection, processing, amplification, and subsequent product analysis. During sample collection and processing, improper handling or the use of contaminated equipment can result in trace amounts of exogenous nucleic acid templates being introduced into the experimental system. Once these foreign nucleic acid sequences enter the amplification cycle, they may be amplified along with the target template, producing non-specific signals. Furthermore, aerosols present in the laboratory environment are also a significant source of contamination, especially when handling high copy number templates. Even a very small amount of amplicons can be transmitted through the air and settle into the reaction tubes, causing cross-contamination.
[0004] To reduce the occurrence of such problems, researchers have taken a series of measures to improve the specificity and reliability of PCR experiments. For example, in experimental design, nested PCR or the introduction of dUTP / UNG systems can be used to increase the specificity of detection, but this means more complex designs and a decrease in testing performance. In experimental operations, strict adherence to aseptic techniques, the use of dedicated PCR work areas, and regular ultraviolet and sodium hypochlorite disinfection are essential, but this may affect the efficiency of the experiment or increase chemical contamination in the laboratory. As for the selection of reagents and consumables, it is necessary to ensure that they are free of DNase / RNase activity to avoid the introduction of exogenous nucleic acids, but this inevitably increases experimental costs. Summary of the Invention
[0005] In view of the above-mentioned shortcomings of the existing technology, the present invention provides a nucleic acid scavenging agent, which can effectively solve the problems of false positive results caused by nucleic acid contamination in the existing PCR technology, multiple sources of contamination, and the current measures to improve specificity and reliability are complicated in design, affect efficiency, increase contamination and have high costs.
[0006] To achieve the above objectives, the present invention provides the following technical solution:
[0007] This invention provides a nucleic acid scavenging agent, comprising solution A and solution B, wherein solution A is the reactive oxygen source component in the nucleic acid scavenging agent, and solution B is the synergistic and auxiliary component in the nucleic acid scavenging agent, and the working concentrations of solutions A and B are within the following ranges:
[0008] Liquid A:
[0009] Urea peroxide: 0.25%-3%, as a reactive oxygen source, can generate excess oxygen free radicals, effectively damaging single-stranded and double-stranded DNA structures;
[0010] Polyvinylpyrrolidone: 0.1%-2.5%, used as a stabilizer to help protect the components of nucleic acid scavengers from degradation;
[0011] Polyethylene glycol 4000: 0.1%-8%, increases solution viscosity, helping reagents to more evenly cover the surface;
[0012] Buffer components and preservatives: ensure the pH of the reagent is stable and extend its shelf life;
[0013] Liquid B:
[0014] Trehalose: 1%-30%, a natural antioxidant that protects horseradish peroxidase from oxidative damage;
[0015] Glycerin: 10%-45%, increases solution stability and prevents drying;
[0016] Collagen peptides: 0.1%-1%, promote cell membrane penetration and enhance clearance effect;
[0017] Horseradish peroxidase: 0.1%-1%, catalyzes the decomposition of urea peroxide, producing potent oxygen free radicals.
[0018] Furthermore, when using the nucleic acid scavenging agent, it is mixed evenly according to the ratio of solution B: solution A = 1:50-1:300, and the optimal viscosity range of the mixture after the nucleic acid scavenging agent is mixed evenly according to the ratio of solution B: solution A is 5mPa·s-20mPa·s.
[0019] Furthermore, the optimal working concentration of urea peroxide in solution A is 1%-2%, the optimal working concentration of polyvinylpyrrolidone in solution A is 0.5%-1.5%, and the optimal working concentration of polyethylene glycol 4000 in solution A is 2%-6%.
[0020] Furthermore, the buffer component in solution A is prepared from a buffer salt or preferably a buffer solution component such as sodium citrate, disodium hydrogen phosphate, and disodium dihydrogen pyrophosphate, with a concentration range of 0.05 mol / L to 0.2 mol / L, maintaining the pH value of the reagent in the range of 6.5 to 8.0. The preservative in solution A is Proclin-300, with a concentration range of 0.05% to 0.2%.
[0021] Furthermore, the optimal working concentration of trehalose in solution B is 10%-20%, the optimal working concentration of glycerol in solution B is 20%-35%, the average molecular weight range of collagen peptides in solution B is 1000-3000 Da, and the optimal working concentration of horseradish peroxidase in solution B is 0.3%-0.7%.
[0022] Furthermore, the method of using the nucleic acid scavenger is as follows:
[0023] Step 1: Store solution B in a brown plastic bottle that can form a spray.
[0024] Step 2: Store solution A in a brown plastic bottle. When using, add an appropriate amount of solution B to the plastic bottle containing solution A.
[0025] Step 3: Spray the nucleic acid remover three times on the target surface, or wipe the surface of the instrument or tool with a paper towel soaked in an appropriate amount of nucleic acid remover. After 5-10 minutes, wipe it with a clean paper towel. When removing airborne aerosol pollution, spray the nucleic acid remover thoroughly in the room, seal it for 1 hour, and then ventilate.
[0026] Furthermore, when the nucleic acid remover is used by spraying, the spray particle size range is 50-200μm to ensure more uniform coverage of the target surface. When removing airborne aerosol pollution, the amount of the nucleic acid remover sprayed per cubic meter of space is 5-10mL.
[0027] Furthermore, the specific preparation method of the nucleic acid scavenging agent is as follows:
[0028] S1. Preparation of Solution A: 0.25%-3% urea peroxide, 0.1%-2.5% polyvinylpyrrolidone, 0.1%-8% polyethylene glycol 4000, 1.05% citric acid monohydrate, 1.41% anhydrous disodium hydrogen phosphate, 0.05% Proclin-300;
[0029] S2. Prepare solution B: 0.1%-1% horseradish peroxidase, 1%-30% trehalose, 10%-45% glycerol, 0.1%-1% collagen peptides, 0.1% Proclin-300;
[0030] S3. Preparation of nucleic acid scavenging agent: When using, solution B and solution A need to be mixed and used immediately. The mixing ratio of solution B to solution A is 1:100.
[0031] The technical solution provided by this invention has the following advantages compared with the known prior art:
[0032] 1. The nucleic acid removal agent provided by this invention does not contain corrosive chemical components such as sodium hypochlorite. This effectively avoids the corrosive damage that traditional chlorine-containing disinfectants may cause to instruments and equipment, which helps to extend the service life of experimental instruments and reduce equipment maintenance costs. At the same time, the free oxygen generated during use will dissipate quickly when it does not bind to DNA, and will not leave harmful chemical substances in the environment. It has the advantages of being non-toxic, harmless, and easy to operate.
[0033] 2. Nucleic acid scavenging agents can effectively destroy single-stranded and double-stranded DNA structures, effectively remove genomic DNA and nucleic acid amplification products. As a reactive oxygen source, urea peroxide can precisely generate an appropriate amount of oxygen free radicals within a specific concentration range, avoiding the problem of affecting the scavenging effect due to excessive or insufficient free radical generation, ensuring that the destructive effect on nucleic acids reaches the optimal state. Compared with traditional scavenging methods, the nucleic acid scavenging agent of this invention has stronger adaptability and higher scavenging efficiency when facing complex nucleic acid contamination situations, which can significantly reduce the probability of false positive results and improve the accuracy and reliability of experimental results.
[0034] 3. Nucleic acid removal agent is easy to operate and does not require complicated special equipment. It can be used in a variety of ways. It can be applied to the surface of instruments, equipment and tools through simple spraying or wiping. When removing airborne aerosol pollution, simply spray the room thoroughly according to the prescribed dosage and close the ventilation. It is easy for laboratory personnel to master and apply, which greatly saves operation time and labor costs and improves laboratory work efficiency.
[0035] 4. Urea peroxide is less irritating than commonly used disinfectants. While ensuring the cleaning effect, it reduces the requirements for protective equipment and ventilation facilities. It is safe and environmentally friendly to use, and will not damage instruments or the environment, nor will it pose a threat to human health. When solution A is mixed with solution B, horseradish peroxidase can quickly promote the release of highly active oxygen free radicals from urea peroxide, thereby achieving the purpose of clearing nucleic acid molecules, providing a safer and more effective solution for molecular biology laboratories. Attached Figure Description
[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.
[0037] Figure 1 This refers to the detection results of Example 2 in this invention;
[0038] Figure 2 This is the detection result of Example 3 in this invention. Detailed Implementation
[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0040] In this invention, the concentration of the component for which protection is sought is the "working concentration", or a mother liquor that can be diluted to that concentration.
[0041] In some embodiments, "water" in "aqueous solution" refers to purified water, laboratory water, reverse osmosis water, distilled water, deionized water, etc. In some embodiments, the reagent also includes a buffer component.
[0042] As used herein, the term "buffer solution / buffer component" refers to an aqueous solution or composition that resists changes in pH when an acid or base is added to it. This resistance to pH changes is due to the buffering properties of such solutions, hence the name buffer solution or buffered solution. Buffer solutions typically do not maintain the pH of a solution or composition indefinitely, but rather within a specific range, such as pH 6–pH 9. Buffer solutions and buffered solutions are generally prepared from buffer salts or preferred buffer components such as sodium citrate, disodium hydrogen phosphate, and disodium dihydrogen pyrophosphate.
[0043] The combined product of the present invention is preferably packaged in the form of separate packaging for each component, but in some embodiments it can also be packaged together.
[0044] In some embodiments, the combined product also includes a specification for performing the above methods.
[0045] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and are not intended to limit the scope of the invention. Unless otherwise specified, all operations are performed under conventional conditions or conditions recommended by the manufacturer. All reagents and instruments not specified are standard products available commercially.
[0046] The present invention will be further described below with reference to embodiments.
[0047] Example 1
[0048] This embodiment provides a nucleic acid scavenging agent, including solution A and solution B. Solution A is the reactive oxygen source component in the nucleic acid scavenging agent, and solution B is the synergistic and auxiliary component in the nucleic acid scavenging agent. The working concentrations of solutions A and B are within the following ranges:
[0049] Liquid A:
[0050] Urea peroxide: 0.25%-3%, as a reactive oxygen source, can generate excess oxygen free radicals, effectively destroying the single-stranded and double-stranded structure of DNA. The optimal working concentration of urea peroxide in solution A is 1%-2%. This concentration range can generate an appropriate amount of oxygen free radicals, achieving a good balance in effectively destroying the single-stranded and double-stranded structure of DNA. If the concentration of urea peroxide is too low, it may not be able to fully destroy nucleic acids, while if the concentration is too high, it may cause unnecessary waste or adverse effects on other components. This preferred range can improve the nucleic acid removal efficiency.
[0051] Polyvinylpyrrolidone: 0.1%-2.5%, used as a stabilizer, helps protect the components of the nucleic acid scavenger from degradation. The optimal working concentration of polyvinylpyrrolidone in solution A is 0.5%-1.5%. This concentration range can more effectively protect other components in solution A from degradation, ensuring that each component remains stable during storage and use, and extending the service life of the reagent.
[0052] Polyethylene glycol 4000: 0.1%-8%, increases solution viscosity, helps the reagent to cover the surface more evenly. The optimal working concentration of polyethylene glycol 4000 in solution A is 2%-6%. This concentration range allows the reagent to cover the target surface more evenly, ensuring that the nucleic acid removal agent can play a full role in the action area, avoiding local omissions or uneven coverage, thereby improving the overall nucleic acid removal effect.
[0053] Buffer components and preservatives: These ensure the pH stability of the reagent and extend its shelf life. The buffer component in solution A is prepared from buffer salts or preferred buffer components such as sodium citrate, disodium hydrogen phosphate, and disodium dihydrogen pyrophosphate, with a concentration range of 0.05 mol / L to 0.2 mol / L, to maintain the pH of the reagent within the range of 6.5 to 8.0. The preservative in solution A is Proclin-300, with a concentration range of 0.05% to 0.2%.
[0054] Liquid B:
[0055] Trehalose: 1%-30%, a natural antioxidant that protects horseradish peroxidase from oxidative damage; the optimal working concentration of trehalose in solution B is 10%-20%, and within this preferred concentration range, trehalose has a better protective effect on horseradish peroxidase;
[0056] Glycerin: 10%-45%, increases solution stability and prevents drying; the optimal working concentration of glycerin in solution B is 20%-35%, which can more effectively increase solution stability and prevent drying.
[0057] Collagen peptides: 0.1%-1%, promote cell membrane penetration and improve clearance effect; the average molecular weight of collagen peptides in solution B is 1000-3000 Da, which can better promote cell membrane penetration and improve clearance effect within this molecular weight range;
[0058] Horseradish peroxidase: 0.1%-1%, catalyzes the decomposition of hydrogen peroxide to generate potent oxygen free radicals. The optimal working concentration of horseradish peroxidase in solution B is 0.3%-0.7%. Within this preferred concentration range, horseradish peroxidase can more effectively catalyze the decomposition of hydrogen peroxide, precisely generating an appropriate amount of potent oxygen free radicals. It works synergistically with other components to enhance the destructive ability to nucleic acids, further improving the nucleic acid clearance effect. At the same time, it avoids the waste of resources and increased costs caused by excessively high enzyme concentrations, and also reduces the risk of poor clearance effect caused by excessively low enzyme concentrations. Under the premise of ensuring clearance effect, it achieves an optimal balance between cost and performance.
[0059] When using the nucleic acid remover, mix solution B and solution A in a ratio of 1:50-1:300 until homogeneous. The optimal viscosity range of the mixture after thorough mixing is 5 mPa·s-20 mPa·s. This suitable viscosity range ensures the nucleic acid remover's applicability in various application scenarios. For example, in spraying operations, a suitable viscosity ensures a sufficiently uniform and fine spray, preventing droplets from being too large or too small, and ensuring a uniform coating on the target surface. In wiping operations, a suitable viscosity allows the reagent to adhere better to the paper towel, facilitating wiping and preventing excessive dripping.
[0060] The instructions for using the nucleic acid remover are as follows:
[0061] Step 1: Store liquid A in a plastic bottle that can form a spray;
[0062] Step 2: Store solution B in a brown plastic bottle. When using, add an appropriate amount of solution B to the plastic bottle containing solution A.
[0063] Step 3: Spray the nucleic acid remover three times onto the target surface, or wipe the surface of the instrument or tool with a paper towel soaked in an appropriate amount of nucleic acid remover. After 5-10 minutes, wipe it again with a clean paper towel. When removing airborne aerosol pollution, spray the nucleic acid remover thoroughly into the room, seal it for 1 hour, and then ventilate. When using the nucleic acid remover, the spray particle size range should be 50-200μm to ensure more uniform coverage of the target surface. When removing airborne aerosol pollution, the amount of nucleic acid remover sprayed per cubic meter of space should be 5-10mL.
[0064] The specific preparation method of the nucleic acid scavenger is as follows:
[0065] Preparation of Solution A: 0.5% urea peroxide, 0.5% polyvinylpyrrolidone, 3% polyethylene glycol 4000, 1.05% citric acid monohydrate, 1.41% anhydrous disodium hydrogen phosphate, and 0.05% Proclin-300;
[0066] Preparation of solution B: horseradish peroxidase 0.15%, trehalose 10%, glycerol 40%, collagen peptides 0.1%, Proclin-300 0.1%;
[0067] Preparation of nucleic acid scavenging agent: When using, solution B needs to be mixed with solution A, and it can be used immediately after preparation. The mixing ratio of solution B to solution A is 1:100.
[0068] Example 2
[0069] Reference Figure 1 Test on the effectiveness of nucleic acid remover in removing nucleic acid contamination from object surfaces;
[0070] Sample wells 1, 2, and 3 contain petri dishes A, B, and C before processing;
[0071] Sample wells 4, 5, and 6 are Petri dishes A, B, and C after treatment with nucleic acid removal agent;
[0072] Sample wells 8 and 9 contain untreated petri dishes D and E;
[0073] Sample well M is a control for nucleic acid electrophoresis;
[0074] Using a pipette, 1 ml of nucleic acid template was spotted into five petri dishes, labeled A, B, C, D, and E. 5 μl of sample was taken from each of dishes A, B, and C. Then, 300 ml of the nucleic acid removal agent from this embodiment of the invention was placed in a clean spray bottle and sprayed onto these three dishes. The same volume of purified water was sprayed onto dishes D and E. After standing for 60 minutes, samples were taken using sterile cotton swabs. The swabs were then immersed in 1 ml of purified water for 20 minutes, and 10 μl was taken to test for residual nucleic acid. The results are as follows. Figure 1 As shown, nucleic acid contamination was detected in both the untreated and untreated samples using the present invention, while the contamination disappeared in the treated samples.
[0075] Example 3
[0076] Reference Figure 2 Test on the effectiveness of nucleic acid remover in removing nucleic acid pollution from indoor air;
[0077] The amplification curves, from front to back, show untreated plates and plates treated with nucleic acid removal agent 1, 2, 3, and 4 times respectively;
[0078] In a small, isolated laboratory, centrifuge tubes containing amplification products were opened, and aerosol nucleic acid contamination was prepared using a high-temperature water bath, followed by 1 hour of incubation. Petri dishes were then placed open on the lab bench and incubated for another hour before being covered and removed. Nucleic acid removal agent was sprayed from top to bottom and from the inside out, ensuring no area was missed. After incubation for another hour, a second petri dish was placed open on the lab bench, and this process was repeated four times. Finally, samples were taken from the petri dishes using sterile swabs and tested using a real-time PCR instrument. The results showed that the concentration of amplification product contamination in the petri dishes treated with the nucleic acid removal agent was significantly reduced.
[0079] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.
Claims
1. A nucleic acid scavenging agent, characterized in that, The product includes solution A and solution B, where solution A is the reactive oxygen species source in the nucleic acid scavenging agent, and solution B is the synergistic and auxiliary component in the nucleic acid scavenging agent. The working concentrations of solutions A and B are within the following ranges: Liquid A: Urea peroxide: 0.25%-3%, as a source of reactive oxygen species; Polyvinylpyrrolidone: 0.1%-2.5%, used as a stabilizer; Polyethylene glycol 4000: 0.1%-8%, increases solution viscosity; Buffer components and preservatives: used to ensure the pH stability of the reagent; Liquid B: Trehalose: 1%-30%, used to protect horseradish peroxidase from oxidative damage; Glycerin: 10%-45%, used to increase solution stability; Collagen peptides: 0.1%-1%, used to promote cell membrane permeability; Horseradish peroxidase: 0.1%-1%, used to catalyze the decomposition of urea peroxide.
2. The nucleic acid scavenger according to claim 1, characterized in that, When using the nucleic acid scavenger, mix it evenly according to the ratio of solution B: solution A = 1:50-1:300, and the optimal viscosity range of the mixture after mixing solution B: solution A is 5mPa·s-20mPa·s.
3. The nucleic acid scavenging agent according to claim 1, characterized in that, The optimal working concentration of urea peroxide in solution A is 1%-2%, the optimal working concentration of polyvinylpyrrolidone in solution A is 0.5%-1.5%, and the optimal working concentration of polyethylene glycol 4000 in solution A is 2%-6%.
4. The nucleic acid scavenging agent according to claim 1, characterized in that, The buffer component in solution A is prepared from a buffer salt with a concentration ranging from 0.05 mol / L to 0.2 mol / L, maintaining the pH value of the reagent in the range of 6.5 to 8.
0. The preservative in solution A is Proclin-300 with a concentration ranging from 0.05% to 0.2%.
5. The nucleic acid scavenging agent according to claim 1, characterized in that, The optimal working concentration of trehalose in solution B is 10%-20%, the optimal working concentration of glycerol in solution B is 20%-35%, the average molecular weight range of collagen peptides in solution B is 1000-3000 Da, and the optimal working concentration of horseradish peroxidase in solution B is 0.3%-0.7%.
6. The nucleic acid scavenger according to claim 1, characterized in that, The method of using the nucleic acid scavenger is as follows: Step 1: Store solution B in a brown plastic bottle; Step 2: Store solution A in a brown plastic bottle. When using, add an appropriate amount of solution B to the plastic bottle containing solution A. Step 3: Spray the nucleic acid remover onto the target surface 3 times. After 5-10 minutes, wipe it with a clean paper towel. To remove airborne aerosol contamination, spray the nucleic acid remover thoroughly into the room, seal it for 1 hour, and then ventilate.
7. A nucleic acid scavenging agent according to claim 6, characterized in that, When the nucleic acid remover is used by spraying, the spray particle size range is 50-200μm to ensure more uniform coverage of the target surface. When removing airborne aerosol pollution, the amount of the nucleic acid remover sprayed per cubic meter of space is 5-10mL.
8. A nucleic acid scavenging agent according to claim 1, characterized in that, The specific preparation method of the nucleic acid scavenger is as follows: S1. Prepare solution A: 0.25%-3% urea peroxide, 0.1%-2.5% polyvinylpyrrolidone, 0.1%-8% polyethylene glycol 4000, 1.05% citric acid monohydrate, 1.41% anhydrous disodium hydrogen phosphate, 0.05% Proclin-300; S2. Prepare solution B: 0.1%-1% horseradish peroxidase, 1%-30% trehalose, 10%-45% glycerol, 0.1%-1% collagen peptides, 0.1% Proclin-300; S3. Preparation of nucleic acid scavenging agent: When using, solution B needs to be mixed with solution A, and it can be used immediately after preparation. The mixing ratio of solution B to solution A is 1:50-1:300.