China Wuhan Desheng Biochemical Technology Co., Ltd Company News

With the development of the times, people pay more attention to the quality of life, home is a warm and comfortable place for everyone to enjoy, but many decoration companies in order to save costs in the choice of paint is not satisfactory.Therefore, in response to increasingly stringent environmental regulations, water-dispersible polyisocyanates have shown importance in various applications in recent years.   At present, water-dispersible polyisocyanates in most applications are non-ionic hydrophilic modification by polyethers.Although this hydrophilic modified polyisocyanate has gained wide market recognition in most applications, it also has certain drawbacks, such as its high viscosity, which requires a considerable shear force to be applied in the construction process to uniformly introduce it into the aqueous medium.In order to avoid these shortcomings, this also gives CAPS an excellent opportunity.Let it find its location in new coatings.   CAPS in Packaging   Ion-modified groups include carboxyl group, sulfuric acid group, hydroxyl group, hydroxy sulfonic acid, etc., but there are still some defects, such as carboxyl-modified polymers are prone to gelation, hydroxy sulfonic acid-modified products are obviously yellow in color, etc.Later, Bayer reported 3-(cyclohexylamino)-propanesulfonic acid (CAPS)-modified polyisocyanate in its patent CN1429240A. The study found that CAPS-modified polyisocyanate could be finely dispersed in water and the product was stable in storage.CAPS-modified polyisocyanate exhibits certain advantages over other ionic or non-ionic modified products.   1. 3-(cyclohexylamino)-1-propane sulfonic acid (CAPS) reacts with aliphatic polyisocyanates (the former is a zwitterionic aminosulfonate) under mild conditions and in the presence of tertiary amine neutralizers, and the resulting urea sulfonate derivatives are excellent emulsifiers.Regardless of salt forming groups, CAPS-modified polyisocyanates have good storage stability and are not turbid.   Even if they contain fewer sulfonate groups, they can get well dispersed emulsions in water.A series of ionized modified polyisocyanates can be obtained for use in various environmentally friendly high quality waterborne two-component polyurethane coatings.These coatings are comparable to general solvent-based coatings in terms of dry, curing and chemical resistance.The new regulations require further reduction of VOC (volatile organic compounds), and the use of these crosslinkers will definitely increase in the future. Compared with solvent-based coatings, they will not lead to a decrease in paint film quality.   2. Closed water-dispersible polyisocyanate curing agent: Closed water-dispersible polyisocyanate curing agent is a kind of closed polyisocyanate curing agent that is hydrophilically modified so that such products can be dispersed in aqueous resin system.Under the condition of high temperature baking, the blocking agent will be unblocked from the system, releasing isocyanate groups, which react with hydroxyl groups.   3. Closed water dispersible polyisocyanate curing agent is mainly used as crosslinking agent in high temperature baking system.At present, the main use is in the Mid-coating of automobile original paint, in addition, there are also some applications in water-based industrial paint.Closed water dispersible polyisocyanate curing agent can also be used with melamine curing agent to reduce costs,and closed water dispersible polyisocyanate curing agent to improve performance.   CAPS is used as a biological buffer in addition to new materials and coatings, in biochemical diagnostic kits, DNA/RNA extraction kits and PCR diagnostic kits, and in buffer solutions for enzymatic chemistry and HPLC separation of alkaline drugs.  

Trimethylolaminomethane, CAS77-86-1, commonly known as Tris, also known as tromethamine, is a very commonly used reagent, which is widely used in industrial synthesis, biochemical testing, and biopharmaceutical fields; The virus transport media sample tube belongs to an important raw material of its configuration solution.   Trismethylaminomethane Tris molecular structure contains one amino group and three alcoholic hydroxyl groups. The amino group and three methylol groups form a methane-like tetrahedral structure around the central carbon atom. Due to the presence of amino groups, Tris is weakly basic in aqueous solution. The amino group can be used as a coordination group to form Tris salts with many acids. Commonly, Tris-HCl, TEA, TEB, Tris glycine, and Tris phosphoric acid are also used. The raw materials used in the virus transport media are Tris and EDTA. The actual TE buffer is Tris plus EDTA.   Tris powder in drum   Adding Tris to the virus transport meida can first maintain the pH value of the sampled sample and act as a biological buffer. The virus and its nucleic acid are relatively sensitive to the environmental pH. The nucleic acid (DNA, RNA) is easily hydrolyzed in acidic solution. It is more stable in neutral or weak alkaline solution. The Tris hydroxymethylaminomethane, PH buffer range: 7.0-9.0, can maintain the stability of the nucleic acid released after the sample to be cleaved to avoid degradation of the nucleic acid, increase the concentration and purity of the nucleic acid, and help to improve the quality of the nucleic acid To ensure the accuracy of subsequent nucleic acid detection and analysis operations.   Tris buffer is a weak alkaline solution. In such a solution, DNA will be deprotonated to improve its solubility. Therefore, Tris buffer is generally used in the dissolution of nucleic acids and nucleic acid extraction. It should be noted that because it is alkaline when disposing the solution, it will absorb carbon dioxide gas that can generate carbon dioxide in part of the air, so the cap of the bottle containing the Tris solution needs to be tightly capped. In addition, the Tris solution is sensitive to temperature. For every increase of 1 degree, the pH value drops by 0.03, and it needs to be maintained at room temperature during configuration.   Tris buffer is more and more widely used, and even has a tendency to exceed phosphate buffer. Because it does not react with calcium, magnesium and heavy metal ions, its performance is superior to phosphate buffer in many aspects. Desheng's products related to Tris include Tris reagent, Tris hydrochloric acid, TEA/TEB electrophoresis electrophoresis gel, etc., which are superior in quality and low in price.  

Due to the impact of the epidemic, the topic of novel coronavirus has become our daily topic. Recently, Wuhan has implemented the national nucleic acid test. When it comes to nucleic acid detection, we will talk about the virus transport media developed and produced by Desheng. What role does it play in nucleic acid detection?               At present, there are two types of virus transport media: inactivated and activated type.               Virus sampling swab is a common method of virus sampling combined with PCR, which can be used for rapid detection of viral diseases. However, not every sample collection place can carry out PCR detection, so it is necessary to transport the collected virus swab samples, so the swab virus transport media came into being.               Desheng’s virus transport media             For different detection purposes, different virus transport medias need to be used. At present, the two widely used transport media have their own characteristics. In order to meet the different requirements of detection and different laboratory conditions of virus detection, it is necessary to sample different transport media.               Virus transport media (inactivated type) can be used to inactivate and preserve respiratory pathogens quickly by using lysate, which makes the samples lose infectivity. The inactivated samples can be matched with a variety of virus DNA/RNA extraction kits, M32/M96 nucleic acid extractor for rapid extraction of nucleic acid, and the respiratory pathogen PCR detection kit for rapid detection. The specificity sensitivity is not affected.               Virus transport media (activated type) contains Hanks liquid base, gentamicin, fungal antibiotics, BSA (V), cryoprotectants, biological buffers and amino acids. The combination of multiple antibiotics has the effect of anti bacteria and anti fungus; BSA, as a protein stabilizer, can form a protective film on the protein shell of the virus, making it difficult to decompose and ensuring the integrity of the virus; the neutral environment constructed by Hanks buffer helps to increase the survival time and infection stability of the virus. The activated virus transport media is usually used for the collection and transportation of clinical influenza, avian influenza (such as H7N9), hand-foot-mouth disease, measles and mycoplasma, Ureaplasma and chlamydia.               Desheng technology has been committed to the R&D and production of virus transport media, carbomer and other products since the resumption of the epidemic, and has achieved a breakthrough victory. The affirmation of customers after use is a great encouragement to us! We will continue to do our products well, not for the immediate interests, only for better development and customer trust.                      

Virus transport media is a kind of liquid to protect the tested substance of virus by immersing the virus sample on the sampling swab in the sampling tube. It is generally divided into two types: one is activated type, which can protect the protein and nucleic acid of virus; the other is inactivated type, which usually contains the lysate of inactivated virus, which can lyse the protein and protect the nucleic acid.   Therefore, the virus transport media added with lysed salt is an inactivated virus transport media. The main purpose of the contained Tris, lysed salt, EDTA, etc. is to lyse the nucleic acid and release the nucleic acid, so as to carry out by subsequent real-time fluorescent RT-PCR Nucleic acid detection, to determine whether the sample contains viral characteristic nucleic acid, that is, whether it is infected with a virus.   Inactivated and activated virus transport media   Nucleic acid is a biological macromolecular compound composed of many nucleotides, including deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). It is one of the most basic substances in life. The virus has a single structure and contains only one kind of nucleic acid and protein, so when the characteristic nucleic acid is detected, the virus is detected. Viruses are parasitic organisms and cannot survive in vitro after sampling. If they cannot be detected in time, they need to be put into the virus transport media. In order to protect the security of the virus detection environment, it is necessary to add a lysed salt to inactivate the virus and release the nucleic acid that can be detected.   Guanidine is a nitrogen-containing organic compound, also known as "iminourea", "imicarbazide", and "carbamidine". Cleavage salts are strong inhibitors of nucleases and facilitate the extraction of complete RNA from RNASE-rich tissues. The lysed salt can not only quickly destroy the cell membrane, but also denature the protein, so that the protein is denatured and precipitated, so that the nucleic acid can get rid of the protein. The inactivated virus transport media containing lysed salt can fully and effectively lyse the cell, so that the nucleic acid in the cell can be fully released, and a higher concentration of nucleic acid is obtained, which is conducive to improving the quality of the nucleic acid and ensuring the accuracy of subsequent operations.   In addition to the inactivated virus transport media, Desheng developed and produced a activated virus transport media, which not only saves the integrity of the virus, but also has a higher detection rate. It can also be used for other research besides nucleic acid detection. The inactivated virus transport media is safer to use, the operating environment requirements are not so strict, and each has its own advantages.

Tris (trihydroxymethylaminomethane) is a weak base with a pKa of 8.1 at room temperature of 25℃ and an effective buffer range of pH 7.0 ~ 9.2.The pH of aqueous solution of Tris alkali is about 10.5. Hydrochloric acid is generally added to adjust the pH value to the desired value, so that the buffer of this pH value can be obtained.Since Tris buffer is a weakly alkaline solution, DNA will be deprotonated in such a solution, thus improving its solubility.If the pH-adjusted acid solution is replaced with acetic acid, a "TAE buffer" (Tris/Acetate/EDTA) is obtained, while a "TBE buffer" (Tris/Borate/EDTA) is obtained by replacing it with boric acid.These two buffers are commonly used in nucleic acid electrophoresis experiments.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 a combination of Tris and EDTA.)1MTris-HCl6.8 and 1.5MTris-HCl8.8 are the most commonly used reagents for SDS-PAGE.   TRIS reagent   Among the conventional operations of genetic engineering, agarose gel electrophoresis is the most widely used.Agarose gel electrophoresis is a conventional method for separating, identifying and purifying DNA fragments.It usually uses a horizontal electrophoresis device to electrophoresis under an electric field with constant intensity and direction.DNA molecules are negatively charged in gel buffers (generally alkaline) and migrate from negative to positive electrodes in an electric field.The rate of DNA molecule migration is dependent on the size and conformation of the molecule.The influence of electric field strength and direction, base composition, temperature and embedded dyes, etc.     Operation process: ① TE buffer: (10 mmol/L Tris-HCl, 1 mmol/L EDTA) Electrophoresis buffer (50XTAE)   ② Electrophoresis buffer (50XTAE): Tris 242g, glacial acetic acid 57.1ml, EDTA (0.5mol/L pH 8.0) 100ml Dilute 50 times with distilled water when used.   ③ Sample buffer (6X): 0.25% bromophenol blue, 0.25% xylene blue, 40% (W/V) sucrose   ④ STET buffer (pH 8.0) (8% sucrose, 0.5% Triton, 50 mmol/L EDTA, 10 mmol/L Tris) 1) Measure 100 ml of TAE electrophoresis solution, add 0.7 g of agarose, mix well, place in microwave oven, heat for 3 minutes, fully dissolve agarose. 2) Close the clean and dry electrophoretic plate with sterilized rubber and seal the edge with a small amount of agarose solution.Place the comb and adjust the distance between the bottom edge of the comb and the electrophoresis plate, generally 1-2 mm is appropriate. 3) When the dissolved agarose solution is cooled to about 50C, add 5 M L of ethidium bromide, and the final concentration of ethidium bromide is 1.0 m g/m L. After mixing, pour the agarose solution into the electrophoresis plate and keep it still without moving. 4) After the gel has completely solidified (30-45 minutes at room temperature), gently remove the comb, remove the tape, and place the gel in the electrophoresis pad. 5) In the electrophoresis process, electrophoresis solution (1'TAE) was added to cover the agarose gel surface with about 1-2 mm electrophoresis solution.

3-(cyclohexylamine)-1-propanesulfonic acid, also called CAPS, is a kind of biological buffer, which is commonly used in biochemical diagnostic kit, DNA/RNA extraction kit and PCR diagnostic kit. The buffer used for enzyme chemistry and HPLC separation of basic drugs is relatively stable, with pKa value of 10.4 and pH buffer range of 9.7-11.1 at 25℃. It is widely used in biochemical analysis and in vitro diagnosis.   CAPS in carton   In addition to the biochemical industry, CAPS is widely used in the following fields:   1. CAPS is widely used as biological buffer: in biochemical diagnostic kit, DNA/RNA extraction kit and PCR diagnostic kit; in enzyme chemistry and HPLC buffer for separation of basic drugs. When caps is used as biological buffer, it needs better purity. Generally, it needs analytical purity. When it is used in industry, the purity requirements are relatively low. However, different treatments should be made for different applications.   2. In industry, CAPS is used for new coatings and materials. CAPS is also the raw material for manufacturing welding materials, air conditioning equipment and lithium metal.   3. It is used as analytical reagent, heat exchange carrier and pharmaceutical industry. It is used for air conditioning, fireworks, dry batteries and lithium metal, as flux and desiccant.   4. For coating industry, it is used as curing agent of water-based isocyanate. The water-based isocyanate curing agent can coexist with resins containing active groups (hydroxyl, carboxyl, amino, epoxy, etc.) for a long time at room temperature.   CAPS has such a wide range of uses and many manufacturers. When selecting manufacturers, attention should be paid to identify qualified manufacturers and avoid intermediaries to make profits from them. Hubei New Desheng Materials Technology Co., Ltd. is located in Guanggu United Science and Technology City C8-2, Gedian Development Zone, Ezhou City, Hubei Province. It has 14 years of research and development and production experience in the field of biochemistry and specializes in the production of biological buffers.The enterprise is ISO 9001 quality management system certification approved and has a good reputation in the industry. It is a trusted manufacturer of biochemical raw materials. It is absolutely wise for you to choose Desheng.

Polyurethane coating is a kind of coating technology which began to rise in the 1960s. In view of the increasingly strict requirements of environmental protection laws and regulations, the environmentally friendly water dispersive polyisocyanate has shown its importance in various application fields in recent years. Although polyether modified polyisocyanates are widely used, they all have one basic disadvantage, especially when they are used as crosslinking agent of waterborne two-component polyurethane coating, higher polyether content is needed to ensure sufficient dispersion, which leads to a long drying time and long-lasting hydrophilicity of the coating. These shortcomings have been solved on the CAPS (3-(cyclohexylamine)- 1-propanesulfonic acid) modified polyisocyanate.           CAPS       CAPS (an amphoteric sulfamate) reacts with aliphatic polyisocyanate under mild conditions and in the presence of tertiary amine neutralizer. The sulfonylurea derivative is an excellent emulsifier. Without considering the influence of salt forming group, CAPS modified polyisocyanate has very good storage stability and the finished product is not turbid. Even if it contains less sulfonate groups, it can also be in water The emulsion with good dispersing state was obtained. Thus, a series of ionic modified polyisocyanates can be obtained, which can be used in various environment-friendly high-quality two-component polyurethane coatings.   These coatings are completely superior to general solvent based coatings in terms of dryness, curing and chemical resistance. With the requirements of new regulations, VOC (volatile organic compounds) content in decoration materials is further reduced, which makes the amount of these cross-linking agents increase greatly. Compared with solvent based coatings, they will not lead to the degradation of film quality. CAPS modified polyisocyanate has been widely used in automobile original paint, repair paint, plastic paint, wood paint, fabric leather paint, printing ink industry, etc. with its excellent performance. The market prospect is self-evident.           Preparation of CAPS modified polyisocyanate       950g polyisocyanate was stirred with 50g CAPS, 29g dimethylcyclohexylamine and 257g 1-methoxypropyl-2-yl acetate under dry nitrogen for 5 hours at 80 ℃, wherein the polyisocyanate is based on hexamethylene diisocyanate (HDI) and contains isocyanurate group, NCO content is 21.7%, average NCO function is 3.5, monomer HDI content is 0.1% and viscosity is 3000mpas. After cooling to room temperature, colorless and transparent polyisocyanate solution can be obtained.           CAPS produced by Desheng company has not only been widely used in the new paint market, but also in the field of biochemical industry. Because it is also a biological buffer, it is widely used in biochemical diagnostic kits, DNA/RNA extraction kits and PCR diagnostic kits. Welcome enterprises and individuals to call for turther consultation.      

Introduction   CAPS, 3-(cyclohexylamine)-1-propanesulfonic acid, an organic chemical, white crystalline powder, CAS1135-40-6, is a biological buffer, commonly used in biochemical diagnostic kits, DNA/RNA extraction kits and PCR diagnostic kits. Buffer for enzyme chemistry and HPLC separation of basic drugs is widely used in the membrane transfer process of protei sequencing. CAPS buffer is composed of CAPS, deionized water, etc., and its pH is adjusted to 11.0 for purificationof fibronectin.   CAPS buffer   Key points of operation   1. SDS-PAGE electrophoresis: according to the conventional conditions (CAPS system: for > = 20kD protein; Tris Tricine system: for low molecular weight protein, also for high molecular weight protein); 2. Methanol concentration: the range of methanol concentration in CAPS electroimprinting buffer is 0-20% (methanol concentration is high, used for low molecular weight protein transfer; methanol concentration is low or even does not contain methanol, used for high molecular weight protein transfer); 3.PVDF membrane treatment: take out the PVDF membrane, soak it in methanol for several seconds, and then put it into the CAPS electroblotting buffer. (Note: the PVDF membrane shall be prevented from drying up after operation. If the membrane is dry, repeat the operation of this step); 4. Gel treatment: remove gel gel and soak in CAPS buffer for 5-10 minutes. (Note: this step can be omitted when transferring some strong basic proteins PI > 9.0); 5. Install the transfer slot: immerse the filter paper and sponge in the electro blotting buffer, then press the electrical imprinting sandwich in the order of sponge, filter paper, PVDF film, gel, filter paper and sponge, and put it into a small electric rotary slot. 6. Transfer conditions: transfer at 50V constant pressure (100-170 MA) at room temperature for 0.5-2h. (Note: drain the bubbles between the gel and PVDF film. For example, the protein above 70 KD should be transferred for longer time); 7. Pretreatment of PVDF membrane dyeing: take out PVDF membrane and rinse it with deionized water, soak it in methanol for several seconds, then dye it; 8. Membrane dyeing: Coomassie brilliant blue dyeing (dissolve 0.1% Coomassie brilliant blue R-250 in 40% methanol/1% acetic acid) for 30-50 seconds (not more than 1 minute), decolorizing with 50% methanol (change decolorizing solution frequently), washing with deionized water fully, and then drying;   CAPS buffer preparation   1. 10×CAPS(100mmol/L) buffer solution is prepared as follows: CAPS, 22.13g; add deionized water to 900ml; adjust the pH value to 11.0 with 2mol/L NaOH (about 20ml), then dilute to 1L, and store at 4℃. 2. CAPS electroimprinting buffer (1×CAPS containing 10% methanol) is prepared by the following methods: 200ml of 10 × CAPS; 200ml of methanol; 1600ml of deionized water.   Other applications   CAPS is also used to manufacture welding materials, air conditioning equipment and raw materials for manufacturing; it is also used to manufacture pyrotechnics; it is used as analytical reagent, heat exchange carrier, and also used in pharmaceutical industry; it is used for air conditioning, pyrotechnics, dry batteries; it is also used as flux and desiccant; it is used for curing agent of aqueous isocyanate in paint industry. Desheng company specializes in R&D and production of various biological buffers, including CAPS, Tris, Bicine, MOPS, etc., with high purity ≥ 99%, stable process, welcome enterprises and individuals to further consultation.

Trimethylolminomethane-Tris base is a kind of buffer which is widely used in the field of biochemistry. Its CAS number is 77-86-1. It has the advantages of stable property, not participating in biochemical process and strong buffering ability. It is widely used in the detection of protein and nucleic acid.   Due to the wide application of Tris, some details need to be noted. Although Tris buffer has strong buffering capacity, it needs to be used carefully when the dilution is too large or the volume of reaction system changes greatly. When the dilution is ten times, the pH change is greater than 0.1, and the pH change of phosphate buffer is less than 0.1.   When preparing nucleic acid agarose gel electrophoresis, the first preparation work is to prepare gel. The quality of agarose gel directly influences electrophoresis efficiency and efficiency. This process takes a long time and saves time to purchase the prepared gel directly.   After the electrophoretic solution is prepared, it can be put into the electrophoresis tank, start sampling, and then turn on the power supply to start electrophoresis. Using TAE/TBE, it generally takes 20-30 minutes to complete electrophoresis, and the voltage is recommended not to exceed 200V. The voltage of TAE is relatively higher than that of tbe electrophoretic solution. The higher the voltage, the faster the electrophoresis rate, but the corresponding resolution will be lower.   The conductivity of tbe is higher than that of TAE. Therefore, compared with TAE, tbe is less likely to cause overheating in the electrophoresis tank, so tbe is recommended for long-term electrophoresis. Boric acid is an inhibitor of enzyme, so if you need to separate electrophoresis DNA for enzyme cutting reaction, TAE is recommended as electrophoresis buffer solution. TAE is better for the separation of longer fragments, and tbe is suitable for fragments less than 300 BP. TAE is more suitable for the recovery of DNA fragments.   Tris, like bicine, is a biological buffer developed and produced by Desheng. In addition, it also has rich production experience in EDTA, virus transportation medium and nucleic acid extraction solution associated with it. Looking forwards to your further consulation.

Tris-trihydroxymethylaminomethane is an organic compound with the molecular formula of (hoch2) 3cnh2. Tris is commonly used in the Tae and tbe buffers (for the dissolution of nucleic acids) in biochemical experiments. Its amino group can condense with aldehydes.   Tris is a weak base, and the pH value of Tris alkali aqueous solution is about 10.5. Generally, hydrochloric acid is added to adjust the pH value to the required value to obtain the buffer solution of this pH value. The effective buffer range of the buffer solution is between pH7.0 and 9.2, but the effect of temperature on the pKa of Tris should be noted. At room temperature 25 ℃, PKA is 8.1.   Because Tris buffer is a weak alkaline solution, DNA will be deprotonated in such a solution to improve its solubility. People often add EDTA into Tris hydrochloric acid buffer to make "Te buffer", which is used to stabilize and store DNA. If the acid solution regulating pH value is replaced with acetic acid, then "TAS / acetate / EDTA" is obtained, and "Tris / borate / EDTA" is obtained when the acid solution is replaced with boric acid. These two buffers are usually used in nucleic acid electrophoresis experiments.   Preparation of Tris HCl and Tris EDTA: 1、 1m Tris HCl (pH 7.4, 7.6, 8.0) to prepare 1000ml Preparation method: a. Weigh 121.1g Tris into a 1000ml beaker. b. Add about 800ml deionized water, and fully stir to dissolve. c. Add concentrated HCl into the following table to adjust the required pH value. pH value Concentrated HCl 7.4 About 70ml 7.6 About 60ml 8.0 About 42ml   d. Dilute the solution to 1000ml. e. Store at room temperature after high temperature and high pressure sterilization.   Note: the solution should be cooled to room temperature before setting the pH value, because the pH value of Tris solution varies greatly with the temperature. The pH value of the solution will be reduced by about 0.03 units for every 1 ℃ rise in temperature.   2、 1.5m Tris HCl (pH 8.8) to prepare 1000ml Preparation method: a. Weigh 181.7g Tris into a 1000ml beaker. b. Add about 800ml deionized water, and fully stir to dissolve. c. Adjust the pH value to 8.8 with concentrated HCl. d. Dilute the solution to 1000ml. e. Store at room temperature after high temperature and high pressure sterilization.   Note: the solution should be cooled to room temperature before setting the pH value, because the pH value of Tris solution varies greatly with the temperature. The pH value of the solution will be reduced by about 0.03 units for every 1 ℃ rise in temperature.   3、 TE is Tris EDTA buffer (10mm Tris, 1mm EDTA, pH7.4, ph7.6, ph8.0). 10 × TE buffer (pH 7.4, 7.6, 8.0) 100mm Tris HCl, 10mm EDTA to prepare 1000ml Preparation method: a. Measure the following solutions and put them into a 1000ml beaker. ①1M Tris-HCl Buffer(pH7.4，7.6，8.0) 100ml； ②500mM EDTA(pH8.0) 20ml b. Add about 800ml deionized water into the beaker and mix evenly. c. After the solution is fixed to 1000ml, it is sterilized under high temperature and pressure. d. Store at room temperature.   Due to the wide application of Tris buffer, in order to highlight the advantages of Desheng company in biological buffer products, we strictly check all aspects of R&D, production and sales, and strive to give the best products to consumers, so that everyone can use them safely, easily and effectively.

  Operation process of Hanks virus transportation medium: （1） Accurate weighing of reagents: select appropriate culture medium according to different fungi and uses, and the reagents required for the culture medium must be pure.   （2） Correction of pH value: put various components of the weighed culture medium into the container, mark and draw lines, heat and dissolve, supplement water, and determine the pH value. It is usually measured by a precision test paper or pH meter with pH of 6.8-8.0. Use 1N NaOH and 1N HCl to adjust the pH value to a suitable range.   （3） Filtration: put the glass funnel on the iron frame, then use gauze with cotton or filter paper to put it in the funnel, pour the above medium into it and filter until it is transparent.   （4） Subpackage: subpackage the filtered culture medium into the medium test tube or triangle bottle (5ml for each tube; 100ml to 150ml for each triangle bottle), pack the cotton plug and wrap it with kraft paper for sterilization.   （5） Sterilization: medium sterilization, commonly used high-pressure steam sterilization. Generally, the nutritional cells of microorganisms are killed when they are boiled in water, but the spores of bacteria have strong heat resistance, so they must be sterilized by high pressure steam to achieve the goal of thorough sterilization. According to the principle that the steam temperature increases with the pressure, that is, the higher the pressure, the higher the steam temperature. Therefore, under the same temperature, high pressure steam sterilization is better than dry heat sterilization. Moreover, in the case of damp heat, the protein is easy to coagulate and denature after the bacteria absorbs water, because the steam has strong penetration and good sterilization effect.   Hanks virus transportation medium     Attention 1. Samples of Hanks virus transportation medium should be detected when they are fresh. In case of bacterial contamination, the bacteria may contain endogenous HRP, and may also produce false positive reaction. If stored for a long time, it can polymerize in ELISA to deepen the background. 2. After the frozen sample is dissolved, the protein is partially concentrated and unevenly distributed. It should be fully mixed, gently and slowly, to avoid bubbles. It can be mixed upside down, and it should not be strongly shaken on the mixer.   3. Turbid or precipitated samples should be centrifuged or filtered first, and then tested after clarification.   Repeated freezing and thawing will reduce the titer of the protein, so if the sample to be tested needs to be preserved for multiple tests, it should be stored in a small amount of sub packed ice. There are some reasons for the straightness of the standard curve in ELISA: whether the preparation of the standard curve is improper, whether the hole washing part is sufficient, whether the reading is inaccurate or whether there is suction error. Find the reason and find the solution.   Storage conditions Due to the different raw materials and requirements, the storage of the medium is slightly different. The general culture medium is easy to be polluted or decomposed by bacteria after being heated and hygroscopic. Therefore, the general culture medium must be kept in a damp proof, dark and cool place. For some culture media (such as tissue culture media) that need strict sterilization, they must be stored in a refrigerator of 2~6℃ for a long time. Because the liquid culture medium is not easy to keep for a long time, it has been transformed into powder.   The Hanks virus transportation medium independently R&D by Desheng has been successfully put on the market, and customers in need are welcome to inquire for details.

Buffer, as a type of substance that can maintain the pH stability of the reaction system, is usually composed of weak acids, weak bases, and their salts or zwitterionic substances. In biological systems, they play crucial roles, such as CO ₂ in photosynthesis and bicarbonate in human plasma. In the field of biochemical testing, Tris buffer and phosphate buffer (PBS) are the two most commonly used, although they each have their own characteristics and application ranges.   Firstly, from the perspective of buffering range, Tris buffer typically has a pH range of 5.0 to 9.2, which varies depending on the acidity of Tris. In biochemical research, Tris buffer has been paid more and more attention because of its wide application range, especially in SDS polyacrylamide gel electrophoresis and other experiments, its use frequency even exceeds that of phosphate buffer. Phosphate PBS buffer has a wider buffering range, covering the pH range of 1 to 12. This is due to the dissociation characteristics of phosphate, which makes the prepared buffer have a wider pH adaptability.   Secondly, from the perspective of application fields, Tris, as an amino buffering agent, has a sodium free characteristic that prevents it from introducing sodium and potassium ions into the system, thereby avoiding the impact on osmotic pressure. In addition, Tris has a relatively small impact on biochemical processes and does not form precipitates with calcium, enzymes, and heavy metal ions, making it suitable for DNA, RNA, and protein related experiments. However, the pH value of Tris is temperature sensitive and the solution is prone to absorbing CO ₂, so special attention should be paid when using it.   Although phosphate buffer has a slightly weaker buffering ability under alkaline conditions, it can dissociate cations and has a salt balance effect, with little impact on the protein structure and biological characteristics of living organisms. Therefore, phosphate PBS buffer is often used in cell experiments. However, it may also form precipitates with calcium, magnesium ions, and heavy metal ions, thereby inhibiting the activity of certain enzymes.   Overall, Tris buffer and phosphate buffer each have their unique advantages and applicability. With the deepening of biochemical research, the application of Tris buffer is becoming increasingly widespread, and there is a trend of gradually surpassing phosphate buffer. However, when choosing which buffer to use, it is still necessary to consider the specific experimental requirements and conditions comprehensively.Desheng specializes in the production of biological buffering agents, with a large quantity in stock. Welcome to consult and purchase!