China Wuhan Desheng Biochemical Technology Co., Ltd Company News

A sudden epidemic caused the virus transport media, and more and more businesses value this market, so batches of virus transport media manufacturers have emerged on the market. This is bound to dazzle buyers. How to choose high-quality products The manufacturer of virus transport media is a very important issue. Desheng tells you several issues that should be paid attention to in purchasing.   1. Is there enough cooperating manufacturers Whether the quality of the product is good or not depends on the sales volume and the cooperating customers. If there are many cooperating customers and the sales volume is considerable, then the reputation of this manufacturer in the industry must be very good. Desheng’s virus transport media has sold a total of 100 Wansheng relies on the trust of customers in the quality of Desheng. After using Desheng’s virus preservation solution, many customers feel very satisfied with the quality and price, and recommend it to other customers. Bai, Desheng’s reputation continues to spread in the industry, and the number of customers and sales gradually increase. 2. Is there enough stock and whether the delivery is timely During the epidemic, the demand for virus transport media is huge, and many customers’ inquiries are more than 1,000 liters. If there is no sufficient stock to support, customers will choose other manufacturers in a blink of an eye, even if they are willing to wait, when the goods are insufficient Under the conditions, if the delivery cycle is long, on the one hand, it will harm the interests of customers. On the other hand, the customer’s sense of buying experience will be very bad. After Desheng upgrades and reforms the equipment, the monthly output can reach the ton level. The delivery is very timely, so don't worry about it at all.   3. Can a trial package be provided Manufacturers who can provide trial sets are rooted in their high trust in their own quality. Desheng believes that only good product quality can tell you with confidence that if you have doubts about product quality, you can try it first. I will come to you to order in large quantities. If the trial is not good, we will do it to make you feel good. Desheng can provide trial equipment. Whether the product is good or not will we know after the trial. Desheng believes that good wine is not afraid of deep alleys, and good products are not afraid of trial.   Desheng took action during the epidemic to ensure the supply of virus transport media in the market. There are currently two models. The inactivated type is characterized by protecting the nucleic acid of the virus, and the non-inactivated type is protecting the integrity of the entire virus. Everyone Can be checked test demand selection.

The luminescent agent acridine ester 194357-64-7 is a kind of luminescent substrate reagent used in chemiluminescence experiments. Its CAS number is followed by its parent acridine ester. According to the different substituent groups, there are many derivatives with different characteristics. This one is called acridine ester nsp-dmae-nhs, which is one of the more commonly used ones.   Chemiluminescent immunoassay CLIA has gradually surpassed enzyme linked immunosorbent assay as the mainstream in vitro diagnostic detection method. CLIA detection method is relatively simple. It does not need to introduce external light source, and only needs the instrument that can detect light to complete the detection, so it is easy to automate the experimental equipment. Moreover, chemiluminescence has higher sensitivity, which can be used for both qualitative and quantitative analysis.     Structure of acridine ester nsp-dmae-nhs   Acridine ester is usually yellow powder, because it is sensitive to light, in order to extend the shelf life, it is usually packaged in opaque brown bottle and stored at low temperature. Compared with luminol, the chemiluminescence efficiency of acridine ester is five times or more, and it can be directly oxidized by hydrogen peroxide in alkaline condition without enzyme catalysis.   Acridine ester nsp-dmae-nhs is a kind of acridine ester containing - NHS group. NHS, namely N-hydroxysuccinimide or N-hydroxysuccinimide, can be directly connected with the primary amino group of protein or antibody, which is convenient to label antibody or protein. -NSP is a propanesulfonic acid group linked to the nitrogen atom of acridine parent. Compared with the traditional acridine ester ae-nhs, NSP has better hydrophilicity. The structure of inner salt of propanesulfonic acid increases its water solubility, which makes it water-soluble with the markers formed by antibody and nucleic acid. The later luminescence detection can be carried out in water.   In fact, the earliest chemiluminescence was found in animals, such as fireflies in summer. Now it has become bioluminescence. In essence, a series of biochemical reactions have taken place in the substances in the body, resulting in the chemiluminescence phenomenon.   At the end of the 19th century, it was found that abiotic organic compounds can also produce chemiluminescence, such as lofenine, luminol, N, n-dimethylaacridine nitrate, acridine ester and so on. Among them, lucigenin is also an acridine compound.   In addition to the acridine ester nsp-dmae-nhs, Desheng also develops and sells five different types of acridine esters, which are also the ones with better market feedback. However, it does not rule out that more types of acridine esters will be developed and put into the market in the future.

Heparin anticoagulant is a kind of reagent used for blood anticoagulation. It is usually used for blood collection tube anticoagulation. It can also be used for medical anticoagulation and beauty products. Heparin was first discovered and named from the liver of animals. It is a kind of mucopolysaccharide sulfate, a natural anticoagulant substance in the animal body, and has unique properties compared with other anticoagulants.   Heparin anticoagulant is different from other anticoagulant sources:   Anticoagulants such as dipotassium EDTA, sodium citrate or potassium oxalate can be directly synthesized or extracted from plants. The sources are relatively wide and the cost of raw materials is not high. The difference between different products is mainly reflected in the purification process and technology; while heparin Anticoagulant is different. It needs to be extracted from the animal body, usually from the small intestine of sheep or pig, and the content is very small. It takes thousands of pigs to extract one kilogram of heparin. There are two main types of heparin anticoagulants commonly used: heparin sodium and lithium heparin anticoagulants.   Bottled heparin sodium   Application characteristics of heparin anticoagulant:   Heparin is a physiological anticoagulant with antithrombin effect and inhibits the activation of coagulation factors V, VIII, XI and other factors, and promotes fibrinolysis. Heparin anticoagulant is usually its sodium, potassium, lithium, ammonium salt, such as heparin sodium, heparin lithium, etc., of which heparin lithium is the best.   Heparin anticoagulant affects the volume of blood cells and rarely produces hemolysis. It is often used for hematocrit, blood pH, blood gas analysis and other biochemical determinations. It is also suitable for red blood cell osmotic fragility tests. Add 1 mL of a solution containing 1 g/L of heparin to each tube, and dry it below 60 ℃ for later use to prevent 5-10 mL of blood from clotting. Heparin anticoagulant blood is not suitable for blood smear examination, because it will have a bluish background during Wright's staining, and it is not suitable for coagulation factor examination.   Preservation of heparin anticoagulant:   Heparin anticoagulant is the same as other anticoagulants. The liquid is easy to absorb moisture or even deteriorate and needs to be sealed and stored. Moreover, because heparin is a kind of mucopolysaccharide, it can provide nutrition for microorganisms, which is conducive to bacterial reproduction. Therefore, new heparin anticoagulant tubes need to be used. The configured heparin solution, the heparin anticoagulant is ready to use.   Compared with other anticoagulants, heparin anticoagulant is more expensive and has better performance for organisms, but it does not mean that it can replace other anticoagulants, but different anticoagulants have different applications in different situations According to the different needs of blood collection tube enterprises, Desheng provides a variety of anticoagulants such as heparin sodium, lithium heparin, dipotassium EDTA, sodium citrate, and a full set of blood collection reagents such as serum separation gel, coagulant, and siliconizing agent.

Tris (trimethylaminomethane, cas77-86-1), as a common biological buffer, is not only widely used as a solvent for nucleic acid and protein, but also one of the main components of protein electrophoresis buffer. In addition, Tris can also produce a variety of cosmetics, chemicals, pesticides, medicine, coating preparation and other products, and is an important intermediate for the preparation of surfactants, vulcanization accelerators, reducing agents and some drugs.   Tris is not only used as a buffer, but also in the field of medicine. As a drug, Tris is also known as tromethamine. When it is called tromethamine, it can be used for the prevention and treatment of metabolic acidosis and respiratory acidosis, and has a reliable alkalizing effect on urine.   Because the alkalinity is too strong, the preparation can only be injected intravenously, and intravenous injection is more irritant and has more adverse reactions. Yunnan University of traditional Chinese medicine has prepared an organic salt of tromethamine, which can be taken orally and injected intravenously. It not only reduces the irritation and side effects of tromethamine, but also has the functions of alkalizing urine, preventing hyperuricemia and gout, and resisting peptic ulcer.   tromethamine powder   The organic salt of tromethamine is prepared by mixing the organic acid acetic acid or lactic acid which can be completely degraded by the body with tromethamine. After injection or oral administration, the acetic acid or soft acid in the solid or solution of tromethamine can be completely and rapidly degraded and enter the liver in the form of salt, and free tromethamine can be obtained after discharge. Acetic acid and lactic acid are completely metabolized into carbon dioxide and water, and the degradation rate of acetic acid is faster than that of lactic acid. Because of its high polarity, stable chemical properties and not easy to be metabolized by the body, the remaining part of tromethamine can alkalize the blood.   Tromethamine entering the body is mainly excreted through urine, and it is not easy to be reabsorbed. Then tromethamine can alkalize the renal tubular environment and dissolve the deposited acidic substances, so as to be discharged from the body. Promoting renal excretion of uric acid is an important strategy for the prevention and treatment of hyperuricemia and gout.   In addition, the organic salt of tromethamine is a weakly alkaline substance with a pH similar to that of blood. Compared with the direct use of tromethamine, the irritation is very low, which can avoid or greatly reduce the adverse reactions and safety problems caused by too strong alkalinity. Moreover, the organic acid solution of tromethamine has a strong pH buffering function, can neutralize or buffer gastric acid, and will not produce gas in the process, so it has the effect of anti peptic ulcer.   Tris (tromethamine) is widely used in medicine, whether as a biological buffer, as a drug itself, or as a pharmaceutical intermediate, or as a pharmaceutical excipient, tromethamine plays a huge role in the pharmaceutical field. Desheng is a professional manufacturer of tris (tromethamine), which has been implemented in batch production, with an average daily output of 1t, and sufficient in stock. Welcome to consult order.

Acridine ester DMAE-NHS can be used for luminescence data collection with a multifunctional microplate reader equipped with an autosampler. Proteins, peptides, antibodies, and nucleic acids can all be labeled with this product. The acridinium ester emits light rapidly under the excitation of basic hydrogen peroxide, so the labeled compound can be detected by collecting photons. This product is mainly used for: chemiluminescence and immunoassay, receptor analysis, nucleic acid and peptide detection, etc. The following mainly introduces the advantages of acridinium ester DMAE-NHS and the calculation method of labeled protein.   Advantages of acridinium ester DMAE-NHS   Compared with traditional acridine esters, DMAE-NHS has higher luminous efficiency, better thermal stability, and stronger hydrophilicity. The chemiluminescence reagent has high photon yield and low background. It is compatible with proteins, antigens, and antibodies. After coupling, the luminous efficiency is almost unaffected, making it an excellent chemiluminescence immunoassay labeling reagent.   Product packaging   Acridinium ester DMAE-NHS also has certain advantages in synthesis. Compared with other acridinium ester chemiluminescent substrates, its synthesis steps are simple, no protecting group strategy is required, reaction conditions are mild, and the product yield and purity are high, and it is not expensive. The chemical reagents and solvents, and the solvents can be recycled, can meet the needs of mass production, and have broad application prospects by reducing the application cost of production and analysis and testing.   Calculating method for the efficiency of acridine ester DMAE-NHS labeling protein   1. Take 100uL of the sample to be tested, and dilute it until Abs280 is between 0.1 and 1.5; 2. Add a small amount of hydrochloric acid to 1 and adjust to pH=1~2 to form a salt solution with yellow characteristics, with an absorption peak at 367nm 3. Test the Abs280nm and Abs367nm of the sample to be tested respectively; 4. Equation1: Acridine ester concentration (mol/L)=Abs367/14650; 5. Correction of protein Abs280 value Equation2: Abs280 (after correction) = Abs280- (Abs367×0.17); 6. Prepare 1mg/ml unlabeled protein solution (e.g. 50ug protein with 50μL labeling buffer), take out 10μL and add 490μL ddH2O (diluted 50 times). Read Abs280nm and multiply by the dilution factor. 7. Calculate the protein concentration (mg/ml)   The acridinium ester DMAE-NHS produced by Desheng not only has simple labeling, but also has high luminous efficiency. Its stability is unmatched by other luminescent reagents. As a professional manufacturer of acridine esters, Desheng has invested in the research and development of acridinium esters. A lot of energy, its products are of high quality and competitive prices. If you are interested in understanding, you can call for consultation. Desheng welcomes you to consult and order.

The chemical name of HEPES buffer is 4-hydroxyethyl piperazine ethanesulfonic acid, cas7365-45-9. HEPES is commonly used in biological buffers, cosmetics, coatings, surfactants, etc. The pH buffer range is 6.8-8.2, which can be used in biochemical diagnostic kit, DNA / RNA extraction kit and PCR diagnostic kit. It has no toxic effect on cells. It is a hydrogen ion buffer, which can control the constant pH range for a long time.   HEPES buffer is often used in cell culture experiments. In the open culture condition, the addition of HEPES buffer can prevent the increase of pH oxidation in the medium, thus maintaining the pH at about 7.0. So, what are the preparation steps and methods of HEPES buffer? Let's introduce them in detail by Desheng.   HEPES powder   Different literatures have different opinions on the preparation of HEPES buffer solution. According to the use, one is pure HEPES + NaOH, the other is HEPES + salt. Various preparation methods are summarized as follows:   1、 Preparation of 500 ml 1 m HEPES, pH = 7.0, stock solution Dissolve 119.15 g HEPES in 400ml distilled water, add 0.5 ~ 1m NaOH aqueous solution to adjust at least the required pH (the effective pH range of HEPES is 6.8 ~ 8.2), then fix the volume to 500ml with distilled water and store at 4 ℃.   2、 HEPES buffer formula with small amount of salt (500ml) HEPES 6.5g, NaCl 8.0g, na2hpo4.7h2o 0.198g, adjust the pH value with 0.5m NaOH solution, and finally fix the volume.   3、 Preparation of 2 × HEPES buffer salt solution Dissolve 1.6g NaCl, 0.074g KCl, 0.027g na2hpo4.2h2o, 0.2g dextran and 1g HEPES in 90ml distilled water, adjust to the required pH value with 0.5m NaOH, and then fix the volume to 100ml with distilled water.   Desheng is a new technology enterprise integrating R & D, production and sales. Its business scope includes "blood collection additive", "in vitro diagnostic reagent", "biological buffer", "pharmaceutical intermediate" and "chemiluminescence substrate". Tris, HEPES, caps, mops are the company's main products.   Desheng's main product biological buffer is a kind of alcohol ammonia fine chemicals with special characteristics. It does not participate in or interfere with the biochemical process. It can be used in the buffer system of life science research and provide a stable pH environment for experiments. Desheng's biological buffer is widely used in in vitro diagnosis, biopharmaceutical, biological beauty, paint and other industries because of its high buffering efficiency and high quality There are dozens of stable customers. Desheng provides one-stop purchasing service. If necessary, you can click the official website to consult customer service.

Since its first application in the 1950s, Carbomer has been highly respected in pharmaceutical circles. Carbomer has been widely used in the research and production of cosmetics and drugs abroad, and has been included in the Pharmacopoeia of many countries, but it is still a relatively new material in China.   Carbomer has many uses in drug punishment. For example, it can be used as a disinfectant gel, Carbomer Eye Drops, Carbomer drug delivery adhesive, Carbomer skin disinfectant gel, and controlled release material. What are the advantages of carbomer as pharmaceutical excipients? Let's give you a solution.   Carbomer powder   Carbomer can be used as ophthalmic gel. At present, the common eye drops used in clinic are short of drug retention in the eyes, resulting in poor drug absorption. But carbomer is different, it not only does not have the above shortcomings, but also in clinical practice it can relieve endocrine disorders, dry eye symptoms caused by insufficient tears, can reduce inflammation and treat presbyopia.   The new bromide eye drops used in the treatment of dry eye disease in clinic is effective because of its short contact time with cornea. Instead, the gel made with carbomer has a significant effect on promoting weeping, and it will produce the greatest effect after 1 hours.   In addition to the ingredients of ophthalmic gel, in the oral protein polypeptides drug delivery system, using carbomer bags around the milk drops can increase the adhesion time between the milk drops and the intestinal wall mucosa. The microemulsion containing carbomer 940 can increase the intestinal absorption of drugs such as desmopressin, while carbomer's protease inhibition and absorption promoting action are also beneficial to increase the drug. Absorptivity.   ​ Carbomer gel   Carbomer 940 is not only easy to smear, but also can absorb tissue solution, which is conducive to the discharge of secretions. It has good stability, smooth and comfortable skin feeling, easy to clean, and good air permeability. Some oral drugs are made into gel through skin, and become topical drugs, which reduces the stimulation of internal organs. When used for skin external use, Carbomer also has moisturizing property, can lubricate skin, protect skin from pollution and stimulation, and has anti infection effect.   It should be noted that carbomer is used as a pharmaceutical excipient and does not have any other drug effects. It is used as gel, thickener, dispersant or suspending agent as a carrier medium for medicine. Desheng is a professional manufacturer of carbomer. Its products mainly include carbomer 980 and carbomer 940. The customer response is very good. Carbomer is a new type of polymer material. Excellent pharmaceutical excipients will play a certain role in promoting the use of new excipients and the research of new preparations in China.

Caps, CAS: 1135-40-6. What we're familiar with is that it's one of the good's buffers. It is widely used in biochemical diagnostic kits, DNA / RNA extraction kits and PCR diagnostic kits. In addition to the applications we know, what other fields are we not familiar with?   In nucleic acid extraction, 3-cyclohexylaminopropane sulfonic acid (CAPS) and 3 - [(3-cholamidopropyl) dimethylammonium] - 1-propanesulfonate (chaps), 3 - (cyclohexylamino) - 2-hydroxy-1-propanesulfonate (capso), and 2 - (cyclohexylamino) ethanesulfonate (ches) were used to prepare the solution for nucleic acid hybridization, which could reduce the yield of non-specific hybridization products, improve the specificity of nucleic acid hybridization, and maintain the stability of nucleic acid hybridization The yield of the target hybrid product was determined. It has important value in the identification of specific pathogens, the diagnosis of genetic diseases and the analysis of gene sequences.     Caps can also be used in a variety of environment-friendly high-quality waterborne two-component polyurethane coatings. Many coatings do not perform well in terms of drying, curing and chemical resistance, while caps performs well. It can be used as water-based isohydroester curing agent and can coexist with resins containing active groups (hydroxyl group, carboxyl group, amino group, epoxy group, etc.) for a long time at room temperature. This is one of the reasons why caps is more and more favored by the water-based coatings market.   In addition to the above uses, caps is also used to improve waterborne coatings, flux for welding materials, heat exchange carrier for air conditioning equipment, raw materials for lithium metal manufacturing process, pyrotechnics, dry batteries, etc.   In addition, caps is more suitable for transferring small molecular weight proteins to PVDF membrane or nitrocellulose membrane as Western blotting transfer buffer or transmembrane buffer; in addition, caps is also used as eluent in cation exchange chromatography, running buffer in capillary electrophoresis, enzyme determination buffer, etc.   Caps buffer with such excellent performance has become a hot demand in the market, both in the field of Biochemistry and home decoration. The caps produced by Desheng company is reagent grade, with a purity of more than 99%. It can not only be used as buffer of in vitro diagnostic reagent, but also be well applied in coatings. Our products have good performance and many cooperative manufacturers. Thank you very much Everyone's trust in us, we will continue to unremittingly provide our customers with high quality products.

Carbomer is a kind of acrylic crosslinking resin which is crosslinked with acrylic acid by pentaerythritol and so on. It is a very important rheological regulator. After neutralization, Carbomer is an excellent gel matrix with thickening, suspension and other important uses. Its technology is simple and its stability is good. It is widely used in emulsion, cream and gel. Although there will be a simple text description on the introduction of each raw material, how much do you know about the full knowledge of carbomer? As a manufacturer of Carbomer, Desheng summarizes the product knowledge of carbomer.   essential information   Name: Carbomer, polyacrylic acid; carboxyl ethylene copolymer Appearance: white powder Solubility: soluble in water, 0.2% 940 soluble in water, white translucent liquid, add triethanolamine or sodium hydroxide to dissolve The liquid was colorless, transparent and sticky gel. Thermal stability: swelling in water, generally at 80 ℃ - 85 ℃ Photostability: carbomer neutralized with triethanolamine or sodium hydroxide solution is easy to dilute under long-term natural light   carbomer powder   Determination method   Method name: Determination of carbomer potentiometric titration Scope of application: this method uses potentiometric titration to determine the content of carbomer. Method principle: the test sample was dissolved in water, titrated with sodium hydroxide titrant according to potentiometric titration method, and the carbomer content was calculated.   Reagents: 1. Water; 2. Sodium hydroxide titrant (0.25 mol / L); 3. Standard potassium hydrogen phthalate Operation steps: take about 0.4g of this product, accurately weigh it, evenly disperse it in 400ml water, stir to dissolve it, titrate with sodium hydroxide titrant (0.25mol/l) according to potentiometric titration method (when it is near the end point, stir at least 2 minutes after each drop). Every 1 ml sodium hydroxide titrant (0.25 mol / L) is equivalent to 11.25 Mg - COOH.   Thickening method   1. Neutralization thickening Sodium hydroxide and triethanolamine are commonly used as neutralizers, which is the reason why carbomer is sensitive to ions.   2. Hydrogen bond thickening Carbomer molecule as carboxyl donor can combine with one or more hydroxyl groups to form hydrogen bond and thicken. This neutralization method takes time. The commonly used hydroxyl donors are nonionic surfactants, polyols and so on.   carbomer gel   Configuration taboo   1. Carbomer discolors with m-diphenol and is incompatible with phenol, cationic polymer, strong acid and high concentration electrolyte. Some antimicrobial agents should also be avoided or used in low concentration. Trace amounts of iron or other transition metals can catalyze the degradation of carbomer dispersions. When carbomer comes into contact with strong alkali substances such as ammonia, sodium hydroxide, potassium hydroxide or strong basic organic amines, a large amount of heat can be generated.   2. Some drugs with amino functional groups can form water-soluble complexes with carbomer. Usually, this situation can be prevented by adjusting the solubility parameters of liquid with appropriate alcohol or polyol.   3. Carbomer can also form pH dependent complexes with some polymer excipients, and adjust the solubility parameters, which can also play a role in this condition.   susceptibility   1. Mechanical shear after carbomer neutralization, long-term stirring or high shear stirring will cause viscosity loss   2. The presence of ions - electrolytes reduce thickening efficiency   3. UV - long term ultraviolet irradiation will make the carbomer gel less sensitive to ultraviolet radiation when its viscosity is reduced by pH>/=10.   4. temperature change carbomer gel is not affected by temperature.   5. microorganism carbomer does not support the growth of bacterial mold, and the growth of bacterial mold does not affect the gel properties. The conventional dosage is 0.2-0.4%, which can replace 3-7% of conventional emulsifier. Carbomer polymer has almost no properties of surfactant, so adding 0.1-0.5% low HLB surfactant can adjust the oil phase particles to be smaller, so as to prepare white and delicate cream products.   purpose   1. Emulsifier   (1) It is effective at very low concentration of 0.1-0.5%, replacing the traditional surfactant dosage of 3-7%; (2) It is not limited by HLB and PLT; (3) It can emulsify any liquid oil at room temperature; (4) If the wax is melted in the manufacturing process, it can be emulsified; (5) The stable emulsions can be prepared by making full use of the wetting, dispersing and adhering functions of surfactants; (6) When rewetting, it will not emulsify again, so it is easy to prepare waterproof emulsion without film-forming agent; (7) High oil phase can be dissolved into water to form (O / W) emulsion; (8) can be prepared: moisturizing cream, lotion, cleansing products, sunscreen products, alcohol free perfume, flavor conditioner (enhanced gloss, easy to comb), hand washing agents, low consistency spray emulsion and transparent microemulsion.   2. Used in skin care products   Hydrophilic thickener, stable emulsifier, suspending agent and gel have good transparency. It is necessary to maintain moderate to weak alkalinity to have consistency. Therefore, it is impossible to coexist with acid active ingredients. In addition, Carbomer is also afraid of salts. Therefore, mineral ions can not be added, otherwise the consistency will disappear and irritation to the eye mucosa.

Carbomer is a kind of nano grade acrylic acid resin. When water is rising and a small amount of mixture is added (such as triethanolamine and sodium hydroxide), a high transparent gel is formed. Different types of carbomer represent different viscosity, such as short rheological or long rheological, such as: carbomer 940 has short rheological property, and its viscosity reaches 63000MPA.S at 0.5%. It is suitable for high viscosity products. Carbopol 941 has long rheological properties, and its viscosity reaches 7500mpa. S at 0.5%. It is suitable for low viscosity products. Carbopol 941 has ion or salt resistance, and is suitable for daily chemical and industrial products.   The thickening mechanism of carbomer is as follows   Neutralization thickening: carbomer is usually neutralized to form salt, which makes the curly molecules thicken due to the opening of electric repulsion force. Sodium hydroxide and triethanolamine are commonly used neutralizing agents, which is also the reason why carbomer is sensitive to ions. Hydrogen bond thickening: as carboxyl donor, Carbomer molecules can combine with one or more hydroxyl groups to form hydrogen bond and thickening. This neutralization method takes time, and the commonly used hydroxyl donors are non-ionic surfactants, polyols, etc.   There are two dissolution methods of carbomer A: The common method is to dissolve every other day. If you want to use it on the next day, soak it on the previous day. First, add carbomer into deionized water according to the actual production requirements to dissolve it without stirring. After carbomer absorbs water naturally, the neutralizer (triethanolamine or sodium hydroxide solution) is added, adjust the pH value to about 7, and use a round tool or disperser And stir evenly at low speed.   B: was dissolved by high-speed dispersant and added to the actual production ratio. The disperser did not have white powder and added neutralizer to form the gel. Then the vacuum emulsification pot was used to remove the air from the gel, and then worry too much.     It should be noted that when using common methods, Carbomer can not be stirred in water. For example, when adding carbomer while stirring, Carbomer will form a white water ball. The surface has absorbed water, but there is no water in it. After neutralization, many water white spots can be seen, and a large number of bubbles can be formed. Carbomer has high viscosity, and bubbles are difficult to eliminate by themselves. Even if a certain amount of defoamer is added, it is difficult to eliminate the bubbles. In this case, the vacuum pot can only be used to eliminate the bubbles, which increases the difficulty of operation to a certain extent.   Warm tips of carbomer dissolution The dispersion time of various types of carbomer in water is related to the water temperature and quality. It is recommended to use deionized water to make the product more stable. If it is dissolved directly in organic solute, it will take longer. For example, for solid alcohol, Carbomer 940, 941, 934, 980 and 981 need soaking for about 8 hours, Carbomer 2020 U10 U20 needs to be soaked for about 4 hours. The specific dissolution time is related to the dissolution amount. If you have more questions, please contact the customer service on Desheng's official website at: www.whdsbio.com

Novel coronavirus pneumonia has been nip in the bud. Recently, the European and South American multi national epidemic situation is again in urgent demand. The three regions of France and Spain, the two Greek area are again blocked, and the emergency situation in many countries is once again extended. Although our country is relatively safe at present, it is also necessary to intensify the prevention and control of the epidemic side to prevent the disease. In response, it is not too much to say that it is a worthy meritorious official to launch an efficient and stable Virus Transport Media to assist nucleic acid detection.   First of all, let's understand the characteristics of the virus. The virus is composed of a nucleic acid molecule and protein or only protein. The individual is small and the structure is simple. The common epidemic infectious diseases are usually RNA viruses, such as influenza virus, HIV and influenza A virus.   Because there is no cell structure, the virus itself can not replicate. Instead, it invades the host cells with genes and uses the latter's replication system to replicate new viruses. What we call COVID-19 is also RNA virus. New Coronavirus is not an independent life body. It needs invasion to live cells. It can reproduce and release more progeny virus particles by using the energy and material and molecular encoding function of living cells.     High concentration guanidine salt can quickly inactivate and preserve respiratory pathogens in inactivated Virus Transport Media, which makes the samples lose infectivity. The inactivated samples can be used with a variety of virus DNA / RNA extraction kits, M32 / M96 nucleic acid extraction instrument for rapid nucleic acid extraction, and PCR detection kit for respiratory pathogens for rapid detection. The specificity and sensitivity are not affected.   In addition to inactivated virus, there are also non inactivated virus. The non inactivated virus contains Hanks solution, gentamicin, fungal antibiotics, BSA (V), cryoprotectants, biological buffers and amino acids. The combination of multiple antibiotics has anti-tumor effect   The function of bacteria and antifungal; bovine serum albumin (BSA) as a protein stabilizer can form a protective film on the protein coat of the virus, making it not easy to decompose and ensuring the integrity of the virus; the neutral environment constructed by Hanks buffer can help to increase the survival time and infection stability of the virus.   Desheng's non inactivated Virus Transport Media has the advantages of good sampling effect and more accurate detection. It can provide free samples of {Virus Transport Media} according to customers' needs. Desheng's Virus Transport Media has both inactivated and non inactivated types, which can meet the different needs of different organizations for Virus Transport Media. Each bottle is packed with 1L and 5L separately, which is convenient to use, with good sampling effect and reliable quality, For you to bring a different use experience. For example, the conventional packaging is 1L / bottle and 5L / barrel. Of course, if you need other specifications, it also supports customization.

HEPES buffer is 2 - (4 - (2-hydroxyethyl) piperazine) ethanesulfonic acid, CAS 7365-45-9. This buffer is usually used in biochemical experiments to adjust the pH value of the reaction system, such as virus preservation solution or cell preservation solution.   There are two types of HEPES buffer on the market: powder reagent and solution reagent. The concentration of HEPES solution is 10-50 mmol / L, and the buffer capacity can be achieved when the culture medium contains 20 mmol / L HEPES. Moreover, this kind of buffer has many advantages over phosphate buffer. It is non-toxic to cells and can control the constant pH range for a long time. It is a good hydrogen ion buffer.   hepes powder   The dissociation constant of HEPES buffer is 7.65 (at 20 ℃), and the pH buffer range is 6.6-8.6, which is generally suitable for the reaction system with pH 6.8-8.2. It can be used directly with sodium hydroxide, or mixed with salt and adjusted pH with sodium hydroxide.   1、 500 ml of 1 mol / L HEPES, pH 7.0, stock solution: weigh 0.5 mol (119.15 g) of hydroxyethyl piperazine ethanesulfonic acid, then adjust to the required pH value with 0.5 m ~ 1 M sodium hydroxide, finally fix the volume with distilled water, and seal at 4 ℃.   2、 HEPES buffer 500ml with a small amount of salt: HEPES ＞ 6.5g, NaCl ＞ 8.0g, na2hpo4.7h2o ＞ 0.198g, adjust pH value with 0.5m NaOH ＞ water solution, finally fix volume and store at low temperature.   3、 Preparation of 2 × HEPES buffer salt solution: 1.6g NaCl, 0.074g KCl, 0.027g na2hpo4.2h2o, 0.2g glucan or dextran and 1g HEPES were dissolved in 90ml distilled water, adjusted to the required pH value with 0.5m NaOH, and then diluted to 100ml with distilled water.   Although the buffer system of HEPES is not as extensive as that of PBS, it has more advantages. The ionic strength of PBS is higher than that of HEPES, and the ionic strength will affect the solubility of other solutes in the mixed solution. In general, where PBS can be used, HEPES can be used, but where HEPES is used, PBS cannot be replaced.   HEPES buffer is similar to pipe, but the water solubility of pipe is poor, so it can be made into sodium salt of pipe. The two buffers provided by Desheng are powder reagents, which can also be prepared into ready-to-use buffer solutions with specific concentrations if required.