China Wuhan Desheng Biochemical Technology Co., Ltd Company News

Blood collection tube additives are the core raw materials in blood collection tubes, and their quality directly determines whether the clinical test can be performed in time, the accuracy of the test results and the reliability of the diagnosis results. As a manufacturer of blood collection tube additives, Desheng has the responsibility and obligation to provide customers and patients with additives of stable quality to ensure the accuracy and timeliness of the test results.   In the past, separation gel was mainly used for serum biochemical testing, that is, separation gel and blood coagulant were used in conjunction. With the development of blood collection tube technology and inspection requirements, more and more blood collection tubes have begun to use separating gel test tubes. At present, there are blood collection tubes (separation gel + potassium salt anticoagulation tube), electrolyte test tubes (separation gel + heparin salt), blood coagulation test tubes (separation gel + sodium citrate) and other varieties of blood collection tubes that use separation gel. These aspects have driven the increasing use of separating glue. But in the process of using it will always encounter various problems.     Serum separation gel A. Difficulty in adding glue: mainly because the temperature is too low. In winter, the temperature drops, the weather is cold, and the viscosity of the separating glue increases, making the process of adding glue more difficult. On the one hand, adding glue in winter is solved by heating. Separating glue generally can withstand high temperatures below 80°C without any problem. Now many equipment manufacturing companies' glue adding machines are equipped with heating function, which provides solutions for blood collection enterprises. In addition, some problems can be solved by reducing the viscosity of the separating glue, but it is not a fundamental solution.   B. Flowing: After the separation glue is added, when the test tube is placed flat, the separation glue flowing distance will be too large, and some even flow to the nozzle of the tube. This is because the intermolecular chemical forces of the separating glue have not been fully recovered during the process of adding glue, and the network state has not been formed. The first solution is to increase the thixotropy of the separating glue, but it will cause difficulty in adding glue; the second is to put it upright for a few hours, and then lay it flat after the thixotropy of the separating glue recovers.   C. Bubble problem: After adding glue and vacuuming, bubbles will appear in the separating glue, or bubbles will also appear after irradiation sterilization. This is because the separation glue clamps air invisible to the naked eye during the glue adding process. After being heated under vacuum or irradiation sterilization, the air in the separation glue slowly expands and becomes visible bubbles. In the process of separating glue production and adding glue, it is necessary to reduce air entrapment in the separating glue as much as possible.   D. The problem that the separation gel does not turn over: Some separation gel blood collection tubes will not turn over clinically, usually because the centrifugal force is not enough, or the centrifugation time is not enough. Increasing the centrifugal force or prolonging the centrifugal time will basically solve the problem. There are also some separation glues that do not turn over due to factors such as aging, which is a quality problem of the separation glue.   E. Flip the separating gel to the serum: This is caused by the too small specific gravity of the separating gel. In recent years, this situation has basically not occurred. Our company once caused this situation due to detection errors around 2010, which caused great problems to customers and the company suffered a lot.   F. Detector alarm: The alarm problem of separation gel blood collection tube often occurs in clinical testing. In the past, the industry always thought that it was caused by the oil droplets or fragments of the separating glue. After years of tracking and analysis, we have found the root cause of this problem. The alarm of the instrument is usually centrifuged under the condition of incomplete blood coagulation, causing the fibrin filaments to float in the serum. When the probe is aspirated, the fibrin filaments are sucked into the probe, causing the instrument to block and alarm.

Dipotassium ethylenediaminetetraacetate is abbreviated as EDTA-2K. Its appearance is white crystalline powder. It is soluble in water and slightly soluble in alcohol. Its aqueous solution has a pH of about 5.3 and a melting point of 272 °C. Dipotassium ethylenediaminetetraacetate has a wide range of uses. It can be used to complex metal ions and separate metals. It is also used in detergents, liquid soaps, shampoos, agricultural chemical sprays, antidotes, and is commonly used in blood anticoagulants.     Dipotassium ethylenediaminetetraacetate (EDTA-2K) Dipotassium ethylenediaminetetraacetate can be used for complete blood counts. Whole blood cell analysis is widely used in clinical testing. Platelet count has become an important basis for the diagnosis and treatment of clinical thrombosis and bleeding diseases, and it is also one of the important parameters for preoperative detection of surgical patients. The International Committee for Blood Standards recommends the use of dipotassium ethylenediaminetetraacetate (EDTA-K2) anticoagulant blood for complete blood counts.   Studies have also explored the detection of total bilirubin (TBIL), direct bilirubin (DBIL), total protein (TP), albumin (ALB), and alanine in anticoagulated plasma and serum of dipotassium ethylenediaminetetraacetate. Differences in the results of 8 liver function indexes including aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltransferase (GGT), alkaline phosphatase (ALP) and so on. Methods The above eight biochemical tests were performed on EDTA-K2 anticoagulated plasma and serum on an automatic biochemical analyzer, and the results were compared and evaluated.   The results showed that EDTA-K2 anticoagulated plasma compared with serum, the results of TBIL, TP, ALB, ALT, AST were not statistically significant, EDTA-K2 anticoagulated plasma ALP was significantly lower than that of serum, the difference was statistically significant, and GGT was slightly lower In serum, the difference was statistically significant, and DBIL was significantly higher than that in serum, and the difference was statistically significant. Therefore, EDTA-K2 anticoagulated plasma can be used for the detection of TBIL, TP, ALB, ALT, and AST. It is not suitable for the detection of DBIL and ALP. For the GGT test results, the reference range of EDTA-K2 plasma should be formulated or multiplied by the correction factor.   Application of dipotassium ethylenediaminetetraacetate (EDTA-2K): 1. Additives for vacuum blood collection tubes: The additive of vacuum blood collection tubes is an aqueous solution of dipotassium ethylenediaminetetraacetate (EDTA-2K), and 4mg of dipotassium ethylenediaminetetraacetate (EDTA-2K) is required for anticoagulation of 2ml of blood. Because the concentration is small, in order not to dilute the blood, 20μl of an aqueous solution containing 200g/L of ethylenediaminetetraacetate (EDTA-2K) 200g/L is generally pre-installed in each blood collection tube. The validity period of the blood collection tube is two years. When the operating environment changes slightly, such as temperature changes, water can easily evaporate to the pipe wall (especially the water in the plastic PET pipe solvent can penetrate the pipe wall and leak out), causing the EDTA-2K in the pipe to crystallize and crystallize quickly When collecting blood, the latter dipotassium ethylenediaminetetraacetic acid blood collection tube is required to be turned upside down at least 8 times in order to fully dissolve and mix the crystallized EDTA-2K in the blood. If the action is too large, the red blood cells will be destroyed and hemolyzed. Gathered and adhered and broken.   2. Prepare toilet deodorant. In parts by mass, it includes the following substances: 5-10 parts of acid salt, appropriate amount of ammonia, 50-70 parts of alcohol, 5-10 parts of urotropine, appropriate amount of dipotassium edetate, appropriate amount of isobutanolamine, water 60 to 80 copies. The deodorant can not only deodorize but also prevent scale, and the method of use is simple, the dosage is small, and the duration is long, and it has no corrosive effect on the toilet. The production method is simple, the raw material cost is low, and it is non-toxic, harmless and non-polluting.   3. Used as a complexing agent in liquid phase analysis. If the invention provides a tetrabutylammonium hydrogen sulfate buffer salt system for liquid chromatography detection, the solvent is water, and the solute includes tetrabutylammonium hydrogen sulfate and a buffer ion pair. The buffer ion pair is composed of potassium dihydrogen phosphate and phosphoric acid The solute also includes a complexing agent, and the complexing agent is preferably dipotassium ethylenediaminetetraacetate.   The tetrabutylammonium hydrogen sulfate buffer salt system provided above is stable within 24 hours without turbidity. Taking the analysis of related substances of moxifloxacin hydrochloride as an example, it can be seen that the tetrabutylammonium hydrogen sulfate buffer salt system stored at room temperature for 24 hours The chromatographic behavior of moxifloxacin, N-methyl impurity, impurity A, impurity B, impurity C, impurity D, and impurity E on the reversed-phase chromatography column is basically the same as that of the newly configured tetrabutylammonium hydrogen sulfate buffer salt system.   4. Prepare metal polishing agent. The polishing agent is based on dipotassium ethylenediaminetetraacetate (EDTA-2K), trisodium phosphate, dibutyl phthalate, sodium silicate, inorganic acid, dicarboxylic acid compound, tetrapolyricinoleate, biological Buffer, stabilizer, water-soluble surfactant, water as raw materials, and through a scientific content ratio, the polishing agent prepared from this can effectively remove impurities on the metal surface. It is not only convenient to operate, but also has a good polishing effect. Improve the production efficiency, and ensure the cleanliness and gloss of the metal surface, and improve the quality of the metal.   Desheng has been committed to the research and development of blood collection tube additives. It has 15 years of production experience and can provide customers with lithium heparin, sodium heparin, dipotassium EDTA and tripotassium EDTA. If you need it, please call for details.

The full name of HEPES is 4-hydroxyethylpiperazine ethanesulfonic acid, CAS is 7365-45-9, HEPES is often used in biological buffers, pH buffer range: 6.8-8.2, the main component of hepes buffer is hydroxyethylpiperazine ethyl Sulfuric acid, HEPES is an amphoteric buffer, which is soluble in water and does not form stable complexes with metal ions. It has a good buffering capacity in the pH range of 7.2-7.4. It is mostly used in biochemical diagnostic kits, DNA/RNA extraction kits and PCR diagnostic kits.   Used in a variety of biochemical reactions: 1. HEPES buffer is often used as a buffer reagent in the cell culture medium of various types of organisms, cell-cell adhesion, short-term cell aggregation and culture, and buffer for cleaning tissues and cells; 2. In protein research, PIPES is often used as the component and eluent of the binding buffer in cation exchange chromatography; 3. In DNA research, PIPES is used as a buffer for calcium phosphate and DNA precipitate formation system, and as a buffer for AFM and electroporation experiments. 4. In addition, HEPES has a certain interference to the reaction between DNA and restriction enzymes, and it is not suitable for Lowry's method to determine protein content. 5. HEPES buffer is often used in the research of organelles and highly variable, pH-sensitive proteins and enzymes, as well as biochemical diagnostic kits, DNA/RNA extraction kits and PCR diagnostic kits. 6. The reaction buffer, pre-hybridization buffer, and hybridization buffer for separating and analyzing RNA nuclear components; used for RNA and T4RNA. Molecular biology grade is used to label the 3'-end of RNA with T4 RNA ligase, separate and analyze the components of the reaction buffer, pre-hybridization buffer and hybridization buffer of nuclear RNA.   HEPES related issues 1. The pH required for most cells is 7.2-7.4, but the appropriate pH for cell culture varies with the types of cells being cultured. Fibroblasts prefer a higher pH (7.4-7.7), while the passage of transformed cell lines requires acidity. pH (7.0-7.4). Since most culture fluids are buffered by the system of sodium bicarbonate (NaHCO3) and CO2, the CO2 concentration in the gas phase should be in equilibrium with the sodium bicarbonate concentration in the culture fluid. If the CO2 concentration in the gas phase or in the incubator air is set at 5%, the amount of NaHCO3 added in the culture solution is 1.97g/L; if the CO2 concentration is maintained at 10%, the amount of NaHCO3 added in the culture solution is 3.95g/L. The cell culture bottle cap should not be screwed too tightly to ensure gas exchange;   2. The pH value of the culture solution using HCO3 and CO2 buffer pair is unstable and tends to be alkaline after storage for a certain period of time. If the pH of the culture fluid changes too quickly, HEPES buffer can be added to the culture fluid to a final concentration of 10-25mM;   3. HEPES is an amphoteric buffer, mostly used in biological research such as oxidative phosphorylation, protein synthesis in a sterile environment, photosynthetic phosphorylation, CO2 fixation, etc.; HEPES has no effect on the substrates of metal ionase and is suitable for transmission In electron microscopy (TEM); in cell culture media, the advantage is that it can maintain a relatively constant pH value during open culture or cell observation. HEPES (25mM) can be used as a substitute for bicarbonate buffer, or as a Addition of bicarbonate buffer (10-15mM) to relieve the restriction of high-concentration CO2 culture environment. Dissolved CO2 and bicarbonate are also very important for good cell growth.

The impact of the epidemic will cause some things to fall and inevitably some things will rise, such as Carbomer. As a cross-linked acrylic polymer, carbomer has good thickening performance and strong suspending ability. In addition to being used in hand sanitizers, it is also widely used in skin care lotions, creams, transparent gels, and hair styling. Gel can even be applied to batteries.   The main functions of Carbomer: 1. Thickening-can produce a wide range of viscosity and fluidity 2. Suspension—make insoluble components permanently suspended in the system 3. Emulsification—plays emulsification and stabilization in the oil/water phase Carbomer thickening mechanism: a. Salt thickening, the most common method is to change the acidic resin into an appropriate salt, so that the curled resin molecules are opened to cause thickening. In water and other polar solvents, use NaOH, KOH, NH40H Such neutralization can easily generate salt; in acute weak or non-acute solvents, organic amines should be used for neutralization. When the resin is used as an emulsifier, in order to achieve the best stability of the oil/water emulsifier, it is necessary to double neutralize the resin with a water-soluble inorganic base and an oil-soluble organic amine, so that the product is soluble in water and oil. Salt acts as a bridge between the oil phase and the water phase.   b. Light bond thickening, adding a hydroxyl donor to the resin, the resin molecule as a carboxyl donor can combine with one or more hydroxyl groups to form a hydrogen bond to thicken. This method takes time, which may range from 5 minutes to several Hours, the consistency can reach the highest value. The PH value of this kind of material is slightly acidic, and the dispersion can be heated to 70°C (but should not exceed) to speed up the thickening. Commonly used polyhydroxy and polyethoxy reaction agents: non-ionic surfactants, solvents, polyols, glycol-silane copolymers, polyethylene oxide, fully hydrolyzed polyvinyl alcohol, etc.     use: Carbomer has excellent thickening, gelling, adhesive, emulsifying, suspending and film-forming properties. As a thickener and emulsifier, it has the following applications in the pharmaceutical industry:   1. Controlled-release drugs made as slow-release materials, such as ascorbic acid, aspirin, lithium carbonate, atropine sulfate, procaine hydrochloride, chlorpheniramine, quinine sulfate, theophylline and so on.   2. The application in the formulation of external medicines, as a carrier matrix to make ointments, suppositories, creams, gels, emulsions, etc.   3. Utilizing the gel, adhesive and film-forming properties of this product, the application in bio-adhesive, as a carrier matrix and bio-attachment made of drugs, it stays in the tissue mucosa for a long time and improves the bio-adhesion of the drug. Utilization, such as targeting mucous membranes, including ocular, nasal, intestinal, vaginal and rectal mucosa.   4. Utilizing the suspending ability of this product, it can effectively suspend insoluble components to form a uniform dispersion system, which is used in oral suspensions, which is safe and effective, avoids odor, maintains stability, and improves bioavailability.   In order to increase production capacity, Desheng actively applies new equipment and expands production staff. While ensuring production capacity, it must also pay attention to product quality. Carbomer series products that are in high demand are Carbomer 940 and Carbomer 980. Desun can provide high-quality Carbomer series raw materials.

Tris base is named tris(hydroxymethyl)aminomethane; tromethamine; tromethamine; 2-amino-2-(hydroxymethyl)-1,3-propanediol. It is a white crystal or powder. Soluble in ethanol and water, slightly soluble in ethyl acetate and benzene, insoluble in ether and carbon tetrachloride, corrosive to copper and aluminum, and irritating chemicals.   Tris is a weak base, and its pKa is 8.1 at 25°C; according to the buffer theory, the effective buffer range of Tris buffer is between pH 7.0 and 9.2. The pH of the aqueous solution of Tris base is about 10.5. Generally, hydrochloric acid is added to adjust the pH to the desired value to obtain a buffer of the pH value. But at the same time, attention should be paid to the influence of temperature on the pKa of Tris.   Tris is often used as a biological buffer, and is often formulated with pH values ​​of 6.8, 7.4, 8.0, and 8.8. Its pH value varies greatly with temperature. Generally speaking, for every degree of temperature increase, the PH value drops by 0.03. tris structure 1M Tris-HCl 6.8 and 1.5M Tris-HCl 8.8 are the most commonly used reagents for SDS-PAGE. And TAE, TBE, etc. prepared by Tris are the most commonly used reagents for DNA electrophoresis, and TE (pH 8.0) is mainly used to dissolve DNA. (TE is the collective name of Tris and EDTA.)   Tris buffer is not only widely used as a solvent for nucleic acids and proteins, but also has many important uses. Tris is used for protein crystal growth under different pH conditions. The low ionic strength of Tris buffer can be used for the formation of the intermediate fiber of C. elegans nuclear lamin (lamin). Tris is also one of the main components of protein running buffer. In addition, Tris is also an intermediate for the preparation of surfactants, vulcanization accelerators and some drugs. Tris is also used as a titration standard.   The Tris buffer developed and produced by Desheng is used for the preparation of buffers in biochemistry and molecular biology experiments; the preparation of pharmaceutical intermediates and the preparation of kits.

Due to a sudden new coronary pneumonia in early 2020, Virus Transport Media appeared in the public eye. But what exactly does it do, I think most people still don't know. Let's first talk about the role of inactivated Virus Transport Media. What is inactivation? Inactivation refers to the use of physical or chemical means to kill viruses, bacteria, etc., but does not damage the useful antigens in their bodies.   Inactivated virus: The high-level structure of the virus protein is destroyed, and the protein no longer has physiological activity, so it loses the ability to infect, cause disease and reproduce, but the conventional inactivation does not affect the primary structure of the virus protein, which means the sequence of the virus protein no change.     Inactivated Virus Transport Media: It is a colorless and transparent liquid, suitable for various types of viruses, new coronaviruses, various influenza, avian flu, hand, foot and mouth urticaria and other viruses. A high concentration of guanidine salt is used to achieve rapid inactivation and preservation of respiratory pathogens, so that the sample loses infectivity. The inactivated samples can be used with the corresponding new coronavirus RNA extraction kit, M32/M96 nucleic acid extractor, etc. to quickly extract viral nucleic acid, and the new coronavirus PCR detection kit can be used to achieve rapid detection without specific sensitivity. influences. Applicable kit methods: fluorescent PCR method, combined probe anchoring polymerization sequencing method, constant temperature amplification chip method, magnetic particle chemiluminescence method, colloidal gold method.   It has the following advantages: 1. Efficiently inactivate viruses to avoid cross-infection caused by centralized sampling 2. Inactivate the virus, reduce the difficulty of storage and transportation 3. The sample loses its infectivity and protects the testing personnel 4. Widely used in PCR laboratory   The product developed and produced by Desheng is suitable for the collection, preservation and transportation of common virus samples such as new coronavirus, influenza virus, hand, foot and mouth virus. Pharyngeal swabs, nasal swabs or tissue samples of specific parts can be collected, and the stored samples can be used for subsequent clinical experiments such as nucleic acid extraction or purification.

Hand-washing sanitizing gel is a daily chemical product that is often used in daily life. Because of the new crown epidemic, it has made it widely welcomed by the public. Carbomer 980, a very important raw material in the sanitizing gel, has also become more and more biochemical. Favored by reagent manufacturers.   Carbomer is used in hand sanitizing gel. The main reason is its thickening, viscosity and permeability. Compared with hand sanitizer, most people prefer gel products. Carbomer can be used to change the solution. It is gel-like, which is more durable and easier to use than liquids. The concentration of carbomer is basically in the range of 0.2%-0.5%. Carbomer can make the liquid system have a special yield value and rheology. Only a very low concentration can make some insoluble additives (particles, oil droplets) Etc.) Achieve permanent suspension.     It is precisely because of the strong levitation ability of carbomer that carbomer is widely used. In addition, carbomer can achieve a good transparency effect when used in hand washing and disinfection gel. After being neutralized and ionized by the carboxyl group, due to the mutual repulsion of negative charges, the molecular chain is dispersed and stretched, showing a greatly expanded state. It is sticky, and these characteristics undoubtedly make Carbomer one of the important raw materials for hand-washing disinfection.   The most notable feature of the use of hand-washing disinfection gel is that it avoids repeated washing, does not need to be washed with water, and can effectively inhibit and remove bacteria from the hands. Especially in summer, the growth rate of bacteria increases, especially intestinal pathogens, pyogenic cocci, yeasts and other pathogens. The main bactericidal component of the hand-washing disinfection gel is ethanol. If it has antibacterial effect, there will be other antibacterial agents, and some use guanidine substances to inhibit bacteria. The content of antibacterial agents is generally a few tenths of a percent, up to 23%, and the national standard also has clear requirements for the content of various antibacterial agents.   With the spread of the new crown epidemic at home and abroad, the supply of disinfection products is in short supply in a short period of time. Especially the disposable hand sanitizer used to sterilize hands when going out has been snatched wildly. Carbomer 980 is used as the free hand sanitizer. As one of the ingredients, many manufacturers have raised their prices. Some manufacturers cannot supply normally because of too many orders. However, as one of the newly developed manufacturers of carbomer products, Desheng can not only guarantee the normal supply of products, but also maintain the prices. Does not rise, is a true conscientious producer.

Carbomer is a copolymer of polyalkyl sucrose or polyalkyl pentaerythritol and acrylic acid cross-linked polymer. It can form a high-viscosity gel at a very low concentration (usually 0.2-1.0%) and is widely used Daily chemical, pharmaceutical and other industries. But it has a lot of models, even with similar names, can these different models be replaced with each other?   The first thing you need to understand is the meaning of different models of carbomer, mainly based on the different materials used in polymerization and the degree of polymerization, so there are a variety of different specifications and models of carbomer. Commonly used in the market are carbomer 980, carbomer 940, carbomer U20, etc., and their thickening performance, emulsification performance, viscosity, shear resistance, etc. are different, so most cases cannot be replaced by each other of. Some characteristics of different carbomers are listed below:     Carbomer Clear Gel Carbomer 940: It is characterized by good thickening performance, extremely short rheology, high viscosity, medium clarity, low ion resistance and high shear resistance, suitable for creams, lotions and gels.   Carbomer 941: It is characterized by stable emulsification system, low viscosity, long rheology, high-definition clarity, medium ion resistance and low shear resistance. Even in ionic solutions, stable emulsions or high Transparent gel.   Carbomer 980: The viscosity is higher than 940, the ion resistance is better than 940, the transparency is equivalent, and it is nourishing than 940 when used in skin care products.   Carbomer U20: excellent dispersibility, high thickening performance, long rheology, good transparency, good suspending ability, stable emulsification system, and no stickiness. It can be used in creams or lotions instead of traditional carbomer 934 , Instead of Carbomer 940 or 980 for transparent gel.   Judging from the characteristics of the respective models, different carbomers are not completely irreplaceable, but generally speaking, the carbomer model used in a product is fixed, but for newly developed products, it is still necessary to test multiple models of carbomer. Therefore, it chooses the best performance, and with the update of technology, the development of better performance carbomers will come out, which will replace some traditional carbomers. Desheng Technology has many years of R&D and production experience in Carbomer and other acrylate polymer materials manufacturers, and welcomes users to communicate!

Carbomer, also known as carbomer, is a polymer formed by chemical cross-linking of acrylic acid or acrylate and allyl ether, including polyacrylic acid (homopolymer) and long-chain alkanol acrylates Polymer (copolymer). Its molecular structure contains 52-68% acid groups, so it has a certain acidity, has hydrophilic properties, and can be dissolved in water, ethanol and glycerin. Carbomer has the functions of thickening, suspending, stabilizing the system, regulating the release of water and active substances, and has simple process and good stability. Therefore, it is a rheological modification widely used in personal care products, pharmaceuticals and other fields. Thickener. There are two main thickening mechanisms of carbomer, including neutralization thickening and hydrogen bond thickening. 1. Neutralization and thickening Because it contains a certain acid group, it needs to be alkaline neutralized during the application process. After being neutralized by alkali, the carboxyl group of the carbomer is ionized. Due to the mutual repulsion of negative charges, the curled molecular chain stretches into a greatly expanded state, which increases the original volume to about 1000 times. To the effect of thickening. Commonly used neutralizers are sodium hydroxide, potassium hydroxide, potassium bicarbonate, and triethanolamine (the pH is adjusted to about 7 to get a crystal clear gel), which is why carbomer is sensitive to ions. 2. Hydrogen bond thickening Carbomer molecules, as carboxyl donors, can combine with one or more hydroxyl groups to form hydrogen bonds and thicken. This reaction mechanism takes time. Commonly used hydroxyl donors are non-ionic surfactants, polyols and so on. In addition, the following points need to be paid attention to when using carbomer. Precautions: 1. All carbomer polymers have the ability of shear thinning, and the longer the shear time, the slower the viscosity recovery, and even the permanent loss of viscosity; 2. Carbopol polymer has poor tolerance to ions, and Carbopol 1342, which is in the transitional stage, is relatively high; 3. Ultraviolet radiation will cause loss of the viscosity of carbomer, and this loss is irreversible.

With the increasing demand for nucleic acid testing projects, Virus Transport Media’s procurement needs are also getting higher and higher. The ingredients of Virus Transport Media are: Hanks Liquid Foundation, Gentamicin, Fungal Antibiotics, BSA (V), Cryoprotectants , Biological buffers and amino acids, etc.   Virus Transport Media is suitable for the collection, preservation and transportation of common virus samples such as new coronavirus, influenza virus, hand, foot and mouth virus. Pharyngeal swabs, nasal swabs or tissue samples of specific parts can be collected, and the stored samples can be used for subsequent clinical experiments such as nucleic acid extraction or purification.     The collection method of Virus Transport Media: 1. Pharyngeal swab: Use two plastic rod swabs with polypropylene fiber heads to wipe both pharyngeal tonsils and back wall at the same time, immerse the swab heads in 3ml Virus Transport Media (also can use isotonic saline solution, tissue culture Discard the tail part of the tube with liquid or phosphate buffer solution), and screw the tube cap tightly.   2. Nasal swab: Gently insert a plastic rod swab with a polypropylene fiber head into the nasal palate in the nasal passage, stay for a while and then slowly turn it out. Take another plastic rod swab with polypropylene fiber head and collect the other nostril in the same way. The above two swabs were immersed in the same tube containing 30% of the sample liquid, the tail was discarded, and the tube cap was screwed tightly.   3. Nasopharyngeal aspiration or respiratory tract aspiration: Use a collector connected to a negative pressure pump to extract mucus from the nasopharynx or extract respiratory secretions from the trachea. Insert the head of the collector into the nasal cavity or trachea, turn on the negative pressure, rotate the head of the collector and slowly withdraw, collect the extracted mucus, and rinse the collector once with 3ml sampling solution (you can also use a pediatric catheter connected to a 50ml syringe Come up to replace the collector).   The cell preservation solution is a general-purpose cell cryopreservation solution, which can be used to freeze human and various animal cell lines; the complete cryopreservation solution formula is ready to use, convenient and fast; non-program cooling, -80℃ low temperature refrigerator freezing Store up to 5 years to ensure the safety of cryopreserved cells; cryopreservable plates (cell culture plates) can be used for cryopreservation of hybridoma cells. The cell preservation solution has a diluting effect and can be separated and embedded in mucus. The effective cells can be preserved, and provide sufficient cell numbers to ensure the accuracy of the test results. At the same time, the processed sample can be completely removed after the low-speed centrifugal filtration of the mucus in the sample, which is effective Prevent mucus from interfering with the sample test results. The cell preservation solution can be made into a uniform monolayer cell sheet after low-speed centrifugation, which meets the inspection requirements.   Apart from professionals, many people often confuse the cell preservation solution with Virus Transport Media, thinking that the two refer to the same preservation solution. In fact, the cell preservation solution is mainly used to freeze cells, and Virus Transport Media has There are two types of fire-extinguishing and non-extinguishing types. The fire-extinguishing type is mainly used for nucleic acid detection. For example, the more popular new coronavirus nucleic acid detection is the fire-extinguishing Virus Transport Media. The non-extinguishing type is mainly used for virus cultivation and reproduction. The biggest feature is that it can provide more accurate test results.

Carbomer is also known as acrylic resin, polyacrylic acid, carbomer resin, carbopol or carbopol. The appearance is white loose powder with a slight special smell. This product is very easy to absorb moisture, so it is placed in a ventilated The warehouse is protected from light and dry to ensure product quality.   Carbomer 940 uses: short rheology, high viscosity, high clarity, low ion resistance and shear resistance, suitable for skin care lotions, creams, alcohol-containing transparent gel products, transparent skin care gels, hair Use styling gel, traveling wave, shower gel, recommended dosage: 0.2-1.0%. Carbo 940 has short rheological properties, and the viscosity reaches 63000MPA.S at 0.5%, which is suitable for products with high viscosity.     Precautions for use of Carbomer 940: Long-term stirring or high-shear stirring after carbomer neutralization will cause viscosity loss; The presence of electrolyte will reduce the thickening efficiency of carbo resin; Long-term ultraviolet radiation will reduce the viscosity of carbomer.   Finally, Carbomer is soluble in water, glycerol and ethanol, and has the characteristics of colloidal solution. The usual concentration is 0.1% ～ 3%. Because its molecular structure contains 52% ～ 68% acidic groups, it has certain acidity. The pH value of 1% water dispersions is 2.5 to 3, and the viscosity is relatively low. When neutralizing with alkali, the viscosity gradually increases with the gradual dissolution of macromolecules, forming a clear solution at low concentration, forming a semitransparent gel at a high concentration. The gel has the greatest viscosity and consistency at pH6 ~ 12, and the viscosity decreases when pH < 3 or pH > 12. Commonly used neutralizers include triethanolamine, ethylenediamine, laurylamine, sodium bicarbonate, sodium hydroxide, etc. generally, 1 g carbomer needs 1.35g triethanolamine or 400mg sodium hydroxide to neutralize. Strong electrolytes and sunlight can reduce the viscosity of the gel. The temperature also has some effect on the viscosity, but the relative change is not great. The gel is best preserved in the refrigerator.

Many things in life cannot be found with the naked eye, so many novel things begin to appear, and luminol becomes one of thousands of things. Luminol, also known as luminol, has a CAS number of 521-31-3. A blood that cannot be observed with the naked eye when detected at a crime scene, and can show a very small amount of blood (occult blood reaction). The chemical name is 5-amino-phthalic hydrazide. It is a blue crystal or pale yellow powder at room temperature, which is a relatively stable synthetic organic compound. The chemical formula is C8H7N3O2.   In fact, the luminol reaction does not necessarily require blood, because blood is just a catalyst, and other methods can also make it glow. And because blood is only a catalyst, even if blood is used, it is extremely obvious that only trace amounts of blood are needed.     Luminol is a strong acid, which has a certain irritating effect on the eyes, skin and respiratory tract. Since hemoglobin contains iron, iron can catalyze the decomposition of hydrogen peroxide, turning hydrogen peroxide into water and monooxygen, and monooxygen oxidizes luminol to make it glow. Therefore, luminol is widely used in criminal investigation, biological engineering, chemical tracing and other fields. In forensic medicine, luminol reaction can identify blood stains that have been scrubbed long ago. Biologically, luminol is used to detect the presence of copper, iron and cyanide in cells.   Luminol/Luminol/Luminol is one of the most commonly used liquid-phase chemiluminescence reagents because of its simple structure, easy synthesis, good water solubility, and high luminescence quantum efficiency. Desheng has specialized in R&D and production of chemiluminescence reagents for 15 years, and has a professional R&D team. If you need luminol, you can directly contact , and look forward to your inquiries!