How to use swab virus preservation solution 1. Before sampling, mark relevant sample information on the label of sampling tube. 2. According to different sampling requirements, use sampling swab to sample in corresponding parts. The specific sampling methods are as follows: a) Nasal swab: gently insert the swab head into the nasopalatine part of the nasal meatus, stay for a while, and then slowly rotate to exit. The other swab swabs the other nostril, immerses the swab head in the sampling solution, and discards the tail. (suitable for sampling with this product) b) Pharyngeal swab: wipe bilateral pharyngeal tonsils and posterior pharyngeal wall with swab. Similarly, immerse the swab head in the sampling solution and discard the tail. (suitable for sampling with this product) 3. Quickly put the swab into the sampling tube (including virus transport fluid). 4. Break the sampling swab at the broken place and tighten the tube cover. 5. Freshly collected clinical specimens should be transported to the laboratory within 96 hours at 4 - normal temperature, and those that cannot be transported to the laboratory within 96 hours should be stored at - 70 â?? or below. The samples should be extracted as soon as possible after being sent to the laboratory. The samples that can be extracted within 24 hours can be stored at 4. If not, they should be stored at - 70 or below
The new crown virus has broken the otherwise peaceful life and messed up people's lives. It is because of the extremely high risk of infection that everyone is afraid and cautious. When difficulties arise, methods to solve them will follow. In order to determine whether they are infected with the new crown virus, nucleic acid testing has made its debut. Nucleic acid testing is an important means to confirm the new coronavirus, and it is also one of the important processes for patients to confirm the diagnosis. To do nucleic acid testing, Nucleic acid detection has the characteristics of early diagnosis, high sensitivity and specificity, and is the "gold standard" for diagnosing new coronary pneumonia. Currently, the most widely used real-time fluorescent quantitative RT-PCR technology. Generally, the two targets located on the ORF1ab and N genes of the virus are detected. The same specimen must meet the double target positive or the repeated test as single target positive, or the two specimens must meet the single target at the same time to confirm the positive of SARS-CoV-2 virus nucleic acid. The virus transport medium developed by Desheng for the new coronavirus is inactivated and non-inactivated. The nucleic acid detection mainly uses an inactivated virus transport medium, which can instantly crack the pathogen and release the nucleic acid, and the protective agent can prevent the nucleic acid from being degraded. . By fully mixing the collected sample with the virus lysis solution and the virus nucleic acid preservation solution, the virus in the sample can be inactivated. Colleagues can effectively ensure the integrity of the virus nucleic acid in the sample. The collected sample can be transported and processed under normal temperature conditions. Long-term preservation. The saved viral RNA samples can be widely used in genetic testing, enzyme-linked immunoassay (ELISA), PCR testing, etc. Although Desheng does not currently have the technology to produce nucleic acid detection kits, it can produce virus preservation solutions, disposable virus sampling tubes and biological buffers required for nucleic acid detection, as well as luminol and acridine as the raw materials for antigen and antibody detection. ester. Desheng is willing to contribute its part in the fight against the epidemic, and is willing to fight for the cause of human health.
The chemical name of the biological buffer HEPES product is: 4-hydroxyethylpiperazine ethanesulfonic acid, a white crystalline powder. It is a weak acid and a zwitterionic buffer in organic chemicals. The decomposition ability of the substance can increase with the increase of temperature, and decrease with the decrease of temperature. However, compared with other buffers, its decomposition constant does not change much with temperature. This makes HEPES buffers more effective at low temperatures. A buffer to keep the structure and function of the enzyme well. It is widely used in many fields such as clinical laboratory diagnostic reagents, life science research, pharmacy and biotechnology. 1) The research of biological buffer HEPES on promoting the stability of foot-and-mouth disease antigen. Foot-and-mouth disease antigen is easily degraded during storage and vaccine preparation, which affects the vaccine effect. The degradation rate of the foot-and-mouth disease antigen is related to the stability of the pH value of the maintenance solution. The preparation of a maintenance solution with strong pH stability can improve the quality of the foot-and-mouth disease vaccine. 2) Preparation of a skin care product containing a biological buffer, which contains a microbial fermentation product extract, which is characterized in that it also contains a biological buffer with a mass percentage of 0.1%-3.0%. Advantages: The pH value of the product has a small drift range. Within three years after the preparation of the skin care product, the pH value can be stabilized at 6.0-8.0, which has a good protection for the microbial fermentation product extract added therein, and the microbial fermentation product extract is not Easily hydrolyzed, the anti-aging effect of the product lasts for a long time. 3) Prepare a neuron-specific enolase content detection kit, which belongs to the field of human neuron-specific enolase content detection. This detection kit has high sensitivity and a wide detection linear range, and has the advantages of simple operation, rapidity, strong specificity, good stability and high sensitivity. In addition to HEPES, the biological buffers produced by Desheng include Tris, Bicine, Caps, Mops, Taps, EPPS, etc.; they are mainly used in biochemical diagnostic kits, DNA/RNA extraction kits and PCR diagnostic kits. Customers in need can provide samples.
Since the outbreak of the epidemic, relevant diagnostic reagent R&D and production companies have introduced RT-PCR nucleic acid detection kits for the first time. By collecting oropharyngeal swab or nasopharyngeal swab samples, the RNA of the virus is extracted and purified for qualitative or quantitative detection. "2019 -New Coronavirus". The sample collection and storage container used in this method is a "disposable virus sampling tube". The new coronavirus nucleic acid detection, disposable virus sampling tube can be said to be indispensable. Next, Desheng intends to introduce the composition and use of the virus sampling tube. About the composition and manufacturing of the virus sampling tube: 1. Sampling swab: The sampling swab directly contacts the sampling site, and the material of the sampling head is closely related to the subsequent detection. 2. Virus preservation solution: There are two main types of virus preservation solution widely used in the market. One is the improved virus maintenance solution based on the delivery medium, and the other is the improved preservation solution of nucleic acid extraction lysis solution. 3. Preservation tube: The material of the preservation tube should be selected carefully. There are data indicating that Polypropylene is related to the adsorption of nucleic acids, especially when the ion concentration of high tension is high, polyethylene plastic (Polyethylene) is better than polypropylene (Polypropylene). Easy to grasp DNA/RNA. About the use of virus sampling tube: The virus sampling tube sampling is mainly divided into oropharyngeal sampling and nasopharyngeal sampling: 1. Oropharyngeal sampling: first press the tongue with a tongue depressor, and then put the sampling swab head into the throat to wipe the bilateral pharyngeal tonsils and back wall of the pharynx, wipe the back wall of the pharynx with light force, avoid touching the tongue unit. 2. Nasopharyngeal sampling: use a swab to measure the distance from the tip of the nose to the earlobe and mark it with your fingers. Insert the sampling swab into the nasal cavity in the direction perpendicular to the nose (face). The distance of the swab should be at least half the length of the earlobe to the tip of the nose. Leave the swab in the nose for 15-30 seconds, gently rotate it 3-5 times, and withdraw the swab. It is not difficult to see from the method of use that whether it is an oropharyngeal swab or a nasopharyngeal swab, sampling is a technical task, which is difficult and easy to contaminate. The quality of the collected sample is directly related to the subsequent testing. If the viral load of the collected sample is Low, easy to cause false negatives, difficult to diagnose.
When the epidemic is waiting for an opportunity again, to quickly control the spread of the virus, nucleic acid testing has become the only way to go, and it has also attracted attention from all walks of life. However, there are many factors that affect the results of nucleic acid testing, including sample collection location, collection method, storage and transportation process, nucleic acid extraction operation, and so on. Among them, the stability of the sample is a key link. How to quickly inactivate the virus and protect the viral nucleic acid from being degraded, maintaining the stability of the virus sample storage solution has become a top priority. Step 1: Break the shell and eliminate the "combat power" Like other RNA viruses, the results of the new coronavirus are simply composed of a protein shell wrapped in single-stranded nucleic acid-RNA. We can simply think of the RNA of the virus as the "brain" that gives orders, and the protein is the "limbs" that execute orders. The new coronavirus infects the human body and reproduces and causes symptoms. This process is mainly completed by the biologically active protein structure outside the virus. The inactivated virus preservation solution is mainly the virus modified by the nucleic acid extraction lysis solution; it is a powerful protein denaturant that can quickly dissolve the protein and cause the virus structure to be broken. When the clinical sample with the new coronavirus is mixed with the preservation solution, the virus in the sample is affected by the lysis solution, and the protein shell is quickly destroyed, and this damage is irreversible. At this time, the virus has lost its evil "minions" and no longer has the ability to infect people, thus ensuring the safety of contacts during sample transportation and processing. Step 2: Inhibit enzyme activity and escort the "ID card" After the shell is lysed, the RNA of the new coronavirus is free in the preservation solution. As a single-stranded macromolecule, the stability of RNA is not as immobile as double-stranded DNA. The RNase that exists everywhere in the natural environment is the culprit that causes RNA to hydrolyze and break. Therefore, it is generally considered that the viral RNA that has lost its outer shell protection is In addition to the inactivated virus storage solution, the virus preservation solution produced by Desheng also has a non-inactivated virus storage solution. It retains the protein coat of the virus and the viral nucleic acid DNA or RNA at the same time, so that the virus has the integrity of the protein epitope and nucleic acid in vitro. Of course, there is a certain risk of infectivity when operating errors. Long-term storage after sampling needs to keep strictly low temperature. Regardless of the virus preservation solution, we need to strictly operate, store or transport in accordance with the requirements when using it.
The inactivated preservation solution is a kind of virus preservation solution, which is mainly used to store the virus after the inactivation of the virus, and the inactivated virus preservation solution can effectively prevent the second infection of the user. Its characteristic is that it can quickly inactivate the virus, degrade the viral protein membrane capsid, and release the viral nucleic acid. At present, the new coronavirus that is sweeping the world in society is to release and degrade RNA viruses, so that post-reverse transcription PCR amplification experiments can be performed to achieve the purpose of using nucleic acid to detect viruses. In addition to the lysing components, the inactivated virus preservation solution usually contains detergents that denature proteins and destroy the membrane structure, biological buffers, inhibitors that prevent nucleases from degrading nucleic acids, and reagents that maintain the stability of the nucleic acid structure. The lysis system may also add protease to cut the protein into small fragments to promote the separation of protein and nucleic acid. At present, there are many known methods for lysing viruses. Two of the more common methods are heating method and concentrated salt method: The concentrated salt method uses high concentration of salt to destroy the secondary bond between nucleic acid and protein, disassociating the nucleoprotein and releasing the viral nucleic acid. Usually, guanidine hydrochloride, guanidine isothiocyanate or non-guanidine salt cleavage salt can be used to directly lyse and inactivate the virus without heating the sample, which is relatively simple. The heating method is based on heating to a temperature value of 80 C ~ 100 C, because generally samples are frozen at -70 C, generally need to be heated for 5 to 10 minutes, this operation is relatively simple, only one step can be used for The template for nucleic acid PCR amplification does not require any operation steps such as centrifugation and extraction, and is faster than the commonly used CheleX100 extraction method and phenol/chloroform methods. Although this method is simple, the amount of nucleic acid extracted will be relatively small. Since the outbreak of the epidemic, Hubei Xindesheng Materials Co., Ltd. has been devoted to the research and development of virus preservation solutions, striving to provide society with its own strength. After many experiments and tests, Desheng has been able to ensure that the product quality and experience are very up to standard. Among them, our company produces inactivated and non-inactivated virus preservation solutions, which can be adjusted and selected on demand. In addition, Desheng reminds our customers that when purchasing virus preservation solutions, you should not blindly pursue low prices. You can take samples separately and go back for testing and comparison. The best is the best.
With the recurrence of asymptomatic, nucleic acid testing cannot be stopped for a moment. This is not only a protection for everyone, but also a protection for yourself. Speaking of nucleic acid testing, we have to bring up our virus sampling tube again. Its choice also plays a key role. Why use a virus sampling tube? Virus detection is different from conventional biochemical detection. The virus itself is a simple microorganism that must be parasitic in living cells. After sampling, the virus leaves the host cell, and its protein shell and nucleic acid will be quickly degraded in the sampling tube, so the nucleic acid During the test, it is impossible to determine whether the initially collected sample contains the virus, and it is easy to cause false negatives. What are the requirements for an excellent virus sampling tube? 1. In terms of sample effectiveness: The non-inactivated virus preservation solution must maintain the activity of the pathogen's infectious agent. Preferably, it can preserve the activity of the virus at room temperature. The inactivated virus preservation solution needs to inactivate the virus but maintain the nucleic acid of the virus to meet the time from sample sampling to laboratory testing. It is necessary to limit and prevent the reproduction of symbiotic microorganisms to ensure the reliability of diagnostic tests. 2. In terms of safety: Because the virus sampling tubes are basically all infectious substances, and some are highly pathogenic infectious substances, the requirements for packaging containers are very strict, and they need to meet safety and ensure that liquids do not leak during transportation. . So what is the virus preservation solution? Under what circumstances do I need to use a virus preservation solution? The virus preservation solution is a protective liquid medium added to the virus sampling tube to protect the sample after the nasopharyngeal swab is sampled. Normally, nucleic acid PCR cannot be directly performed at the sample collection site during nucleic acid detection. If the sample collected by the swab needs to be transferred and transported, it is necessary to add a virus preservation solution. Why is the virus preservation solution divided into inactivated and non-inactivated? After the virus samples are collected, there is usually no way to test in time at the sample sampling site, so the collected virus swab samples need to be transported, and the virus itself will be quickly lysed outside the body and affect subsequent testing, so when storing and transporting , You need to add a virus preservation solution. For different detection purposes, you need to use different virus preservation solutions and different virus detection experimental conditions, so it is divided into two types of preservation solutions, inactivated and non-inactivated. There are no other microorganisms, causing the virus to decompose after sampling or other influences causing false detections.
When it comes to anticoagulants, many people don't understand what they are used for. Simply put, anticoagulants are chemicals that prevent blood clotting. It is very commonly used in blood collection tubes used in hospitals to collect blood for testing. In different blood tests, the applicable anticoagulants are also different. Commonly used anticoagulants include EDTA, sodium citrate, heparin, etc. Let's take a look at the mechanism of action of these anticoagulants. Because blood coagulation is divided into three main stages: first, prothrombin activator is formed; second, prothrombin activator catalyzes the conversion of prothrombin into thrombin; third, thrombin catalyzes the conversion of fibrinogen into fibrin . In these three stages, the participation of calcium ions is required, so once the chelated calcium ions are removed, the blood loses the necessary conditions for coagulation and cannot be coagulated. 1. EDTA (ethylenediaminetetraacetic acid) There are three different forms of EDTA ethylenediaminetetraacetic acid anticoagulant, namely EDTA dipotassium, EDTA tripotassium, and EDTA disodium. Tripotassium EDTA is relatively easier to dissolve and is more popular than other forms. EDTA plays an anticoagulant effect mainly by chelating calcium ions and removing free calcium ions. 2. Sodium citrate Sodium citrate combines with free calcium to form a sodium citrate complex, which consumes calcium to achieve anticoagulant effect. The recommended anticoagulant concentration is 3.2% or 3.8%. The ratio of anticoagulant to blood is 1:9 and 1:4. Blood after sodium citrate anticoagulation cannot be used for compressed cell volume (PCV), hemoglobin (Hb) estimation, total white blood cell count TLC, and differential white blood cell count (DLC) because citrate is used as a solution and it changes blood concentration. 3. Heparin Heparin is an acid mucopolysaccharide with affinity for blood proteins and can be used as antithrombin and antithromboplastin. It prevents the conversion of prothrombin into thrombin, thereby playing an anticoagulant effect. As an anticoagulant, heparin is often used in emergency biochemistry and blood rheology testing.
Choice of nasopharyngeal swab: The main indicators of clinical evaluation of swab performance are the absorption capacity and release capacity of the swab to the target sample at the sampling site. Nylon flocking swabs are made of fine nylon fibers adhered to a plastic rod. Compared with traditional cotton swabs, the adsorption surface is significantly larger, which is conducive to the adhesion and release of pathogenic microorganisms. The ability of nylon flocking swabs and traditional rayon cotton swabs to recover and release known microbial inoculums (spiked samples) confirms that nylon flocking swabs have the ability to release cells, microorganisms, viruses and other microorganisms Significant advantages. Compared with traditional rayon cotton, nylon flocking swabs or foam swabs have a significant advantage in the virus recovery rate in the screening of nasal cavity carrying MRSA virus. For the choice of virus preservation solution: non-inactivated preservation solution and inactivated preservation solution.
