China Wuhan Desheng Biochemical Technology Co., Ltd Company News

In the related biochemical testing of enzyme preparations, in addition to measuring the content, concentration, and stability of various indicators to be tested, there are also indicators for detecting enzyme activity, such as blood sugar, blood lipids, and creatinine. For indicators such as transaminase and sarcosine oxidase, enzyme activity needs to be measured.   Generally speaking, enzyme activity is the activity of enzyme catalysis, which involves a kinetic parameter of the enzyme-the Michaelis constant Km, which means the concentration of the substrate (S) when the enzymatic reaction reaches half of the maximum speed (Vm) . The speed of the enzyme reaction is not uniform, not linear like the concentration, but the number of meters in Changshu is constant, which is a characteristic physical quantity of the enzyme. The Michaelis constant of the enzyme changes with the measured substrate type, reaction temperature, pH and ionic strength. Under the same conditions, no matter what the concentration of the enzyme is, the concentration of the required substrate is the same when the maximum reaction rate is reached.   Measurement method of Michaelis constant of sarcosine oxidase: Prepare a sarcosine solution with a concentration of 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0mmo1/L with Tris-HC1 buffer of pH 8.0, and react at 37°C for 5 minutes Determine the initial oxidation activity of SOX at different sarcosine concentrations. The reaction rate V and 1/V are obtained. According to the Lineweaver-Burk double reciprocal mapping method, with 1/[s] as the abscissa and 1/V as the ordinate, the Km and Vmax of SOX to sarcosine were calculated.   Conclusion of Michaelis constant of sarcosine oxidase: The Michaelis constant can be used to judge the specificity of the enzyme. The smaller the Km value, the greater the affinity between the enzyme and the substrate, and the more suitable the substrate is as the natural substrate of the enzyme. According to the test and calculation of sarcosine oxidase above, the Michaelis equation is y=1232.5X+8.7012 and the correlation coefficient is 0.9947: the calculated Km and Vmax values ​​of SOX to sarcosine are 141.6mmol/L and 0.115mmol, respectively /(L.min).   It should be noted that sarcosine oxidase SOX from different sources has a certain difference in the Michaelis constant of sarcosine. For example, the Km value of SOX from Corynebaclerium to sarcosine is 21mmol/L. Since the Michaelis constant has nothing to do with the concentration of the enzyme and the type of enzyme, this point can also be used for enzyme identification or determination. Desheng Biochemical focuses on the field of biochemical detection, and provides a variety of enzyme preparations including SOX, cholesterol esterase, glucose oxidase, etc.

It rained and dredged the wind last night. I worked overtime to improve the steps. I asked the researcher, but the result was the same. "Do you know? Do you know? It only makes people lose weight." In the face of heavy and arduous R&D tasks, how to choose the right enzyme preparation? How to maximize the effectiveness of raw materials? These problems have plagued countless people. If you learn to read the instructions of enzyme preparations correctly, perhaps these problems will be solved. 1. Understand the color of enzyme powder In vitro diagnostic reagents will be marked with the color of the liquid reagent when they are registered. The color of enzyme preparations will affect the color of reagents after feeding; for example, COX, FPOX, SOX, etc. are all light yellow or yellow powders, and most of the reagents prepared are also light yellow or yellow. It is important to choose an enzyme preparation with an appearance color similar to the registration information. It is not only necessary to carefully check the packaging before feeding, but also to check whether the appearance of the enzyme preparation powder is consistent with the description in the instructions. 2. Understand the specific activity parameters of enzyme preparations When calculating the feeding amount, the specific activity is a parameter that must be understood, and the feeding amount can be determined after conversion. In addition, specific activity is also an important parameter for comparing enzyme preparations. The enzyme preparation itself is a protein powder, which can be used as a nutrient for the growth of microorganisms, which will introduce pollution. Choosing enzyme preparations with high specific activity can reduce the amount of feed, reduce the problem of microbial contamination, increase the shelf life of diagnostic reagent products, and improve product quality. 3. Understand the pH range of enzyme preparations People have their own comfort zone. They don't like severe cold or intense heat. They like to breathe freely in the fresh air. The same is true for enzyme preparations. Each enzyme preparation has its own optimum range. Only at a certain pH and temperature can the enzyme preparation be stimulated to maximize its catalytic activity. Find the optimum pH value from the instructions, and then set the pH value of the reagent within this range, so that the enzyme molecule can work in the best state. 4.understand the interfered substances of enzyme preparations The activity of enzyme preparations will also be interfered by the required substances, such as metal ions such as Ag+, Hg2+, Fe3+, etc. The instructions will also list common interfering substances, which is convenient for production personnel to avoid the introduction of such substances during the development and production of reagents. Enzyme activity. The above important information can be found in the "Enzyme Preparation Manual". As a professional manufacturer of enzyme preparations, Desheng Technology can not only provide enzyme preparation raw materials comparable to imported brands, but also has diagnostic reagent development experience and can provide Mature diagnostic reagent products.

Tris is also called tromethamine, cas77-86-1. Trihydroxymethyl aminomethane (Tris base) is often used as biological buffer, TAE and tbe buffer (used for nucleic acid dissolution) are commonly used in biochemical experiments. What other applications does it have? Now let's take a look.   In the field of medicine, Tris is not only an important pharmaceutical intermediate, but also a drug itself. It is suitable for metabolic acidemia, respiratory acidemia and other diseases, especially in the treatment of hyperuricemia, with ideal effect.   Hyperuricemia can be divided into primary hyperuricemia and secondary hyperuricemia, mainly due to excessive source or (and) insufficient excretion of uric acid. Under normal circumstances, if the level of uric acid in men is higher than 420 μ mol / L and that in women is higher than 360 μ mol / L, it is hyperuricemia. According to social understanding, the high incidence age of hyperuricemia is middle-aged and elderly men and postmenopausal women, and there is a trend of younger in recent years.   At present, the prevention and treatment strategies of hyperuricemia mainly include reducing intake, inhibiting endogenous synthesis, and promoting renal excretion. Among them, promoting renal excretion is mainly achieved by alkalizing urine and inhibiting uric acid transporter. Inorganic metal cations such as Ca2 +, Mg2 +, NH4 + in urine can inhibit the dissolution and excretion of uric acid, while alkaline factors can promote the dissolution of uric acid. Therefore, trimethylolmethane and sodium bicarbonate are often used in this process. However, trimethylolmethane is better than sodium bicarbonate in promoting the dissolution and excretion of uric acid.   After taking sodium bicarbonate, the increased cationic Na + will further antagonize HCO3 alkalization of urine and blood, and promote the dissolution and excretion of uric acid. When sodium bicarbonate exceeds a certain dose, it will even reduce the solubility of uric acid. However, sodium bicarbonate can be produced endogenous. There is sodium bicarbonate in the human body, and there is a great fluctuation in the urine, so the concentration of sodium bicarbonate is not easy to control. If you take a small amount of sodium bicarbonate, the effect of excreting uric acid is not good. If you take more sodium bicarbonate, it may aggravate the deposition of uric acid in the urinary system, and the intake of sodium salt will also increase the cardiovascular and renal burden.   Tris is an organic amino base without inorganic cations, which can avoid or weaken the inhibition of inorganic cations. In addition, Tris is a foreign substance, so the body will not produce Tris. Therefore, the concentration of Tris in the body is better controlled than that of sodium bicarbonate in the course of medication The dissolution of uric acid promoted by trimethylaminomethane was better than that by sodium bicarbonate.   Desheng has been making deep research on biological buffers, and can provide high-quality raw materials such as Tris, bicine, HEPES, etc. Desheng adheres to the company's philosophy of "quality first, technology leading" to provide customers with high-quality products.

Introduction:   Carbomer 940, CAS 9003-01-4, also known as carbomer 940, is a kind of high molecular polymer cross-linked by acrylic acid and acryloyl sucrose or acryloyl pentaerythritol. It is a white loose powder with characteristic slight odor and strong hygroscopicity. Its average water content is 8%. Carbomer resin exists in water in the form of acid. It is easy to swell in water and polar organic solvents (such as ethanol, glycerin, etc.) Characteristics of colloidal solution. Because of 56% - 68% carboxylic acid group in the molecule, these resins are weakly acidic. Although they are weaker than acetic acid, they can easily react with inorganic bases and organic bases to form salts.   Because of its swelling and weak acidity, it is a very important rheologic regulator. The neutralized Kabo resin is an excellent gel matrix with thickening, suspension and other important properties. It has high transparency, high viscosity, strong suspension ability, very short rheology and thixotropy, low ionic shear resistance, simple process and good stability. It is widely used in shampoo, shower gel and bath. Cream, cream and other cream products are especially suitable for transparent products. The most important point is that carbomer 940 is mild and not irritant to skin. Carbomer 940 powder matters needing attention:   1. PH value: the best pH value range of Carbopol 940 is 4-10, higher or lower than this range will lead to changes in the viscosity of the system.   2. The components in the formula that are not easy to be compatible: protein, PVP resin, polyethylene glycol (PEG), polyethoxylated surfactant will interact with the non neutralized Carbopol 940, and it is necessary to partially neutralize Carbopol 940 before adding.   3. The presence of electrolyte will reduce the thickening efficiency of Carbopol resin: Carbopol 940 is sensitive to salt and cation, when the concentration of soluble ion in the component is greater than 0.1%, the dosage of the component should be reduced appropriately.   Deionized water can be used as the matrix of the main material, and salt can be added after neutralization to master the influence of salt on the system. High valence ions (CA, Mg, Fe, AI) will cause serious damage to the system and should be removed. The Fe and Cu converted in the production process will reduce the viscosity of the system and lead to the instability of the system. Stainless steel or non-metallic equipment can be used to prepare products to avoid such effects. In addition, adding EDTA to chelate metal ions can also achieve good results. In addition to the above methods, the appropriate model of Carbopol 940 (such as Carbopol 940l342ge resin) can also be selected, which has low sensitivity to soluble salts.   4, insoluble matter: when there are insoluble components, carbo 940 system is difficult to present clear and transparent gel, and solubilization technology can reduce or eliminate this effect.   5. High shear agitation and pump delivery: carbo 940 is thickened by forming a gel skeleton. After Carbopol neutralization, high shear stirring, long-term stirring, grinding or pump chipping will damage its skeleton and cause viscosity loss, so pipeline homogenizer should be used. Use low shear pumping, such as reciprocating diaphragm pump or gear pump.   6. Long term UV irradiation can reduce the viscosity of carbomer resin.   7. Packing: it can be sealed with moisture-proof and airtight plastic bags, and then packed in cardboard boxes. Carbomer 940 has strong hygroscopicity. During storage, attention must be paid to sealing, and care must be taken to avoid moisture absorption and caking in the exposed air. If there is slight caking, it can become loose powder by gently patting and pressing, which will not affect the thickening effect. After use, it is better to put it in a sealed container with desiccant.   8. Transportation: carbomer is polyelectrolyte, sometimes static when rubbing or extruding resin particles. In case of splashing, remove the dry powder with a broom first. Do not rinse with water. Otherwise, it will form very slippery gel on the ground or equipment.   Hubei xindesheng company specializes in providing carbomer 940, 980 products and after-sales technical support. If you have any questions, please call for details.

1. As an inducer and self-oxidant Luminol is a light inducer and self-oxidant. It can be used as a free radical detection reagent as well as a photosensitizer. In PCL analysis, auto-oxidation is inhibited by a single or a group of antioxidant compounds in the nanomolar range. The antioxidant potential of the sample can be measured by studying the lag phase at different concentrations. 2. Detection of blood luminescence reagent The blood absorbs ultraviolet rays and turns black. After chemical treatment, the blood will also fluoresce. Luminol is commonly used to produce this chemiluminescence, which is a reagent that reacts with catalase in hemoglobin in the blood. 3. Time interval used to identify skeletal remains As the femoral PMI increases, chemiluminescence decreases. In femurs with a PMI of 1 month to 3 years, strong chemiluminescence is observed after a few seconds. Patients with a PMI of 10-15 years have clear chemiluminescence, and 80% of the samples are visible to the naked eye; femurs with a PMI of 25-35 years have weak chemiluminescence in 33% of the samples. Femurs with a PMI of 50-60 years have only a weak response observed in a single femur. No chemiluminescence was observed in femurs whose PMI was over 80 years old. 4. Detect the influence of serum prostate specific antigen The prostate-specific antigen in serum can be detected by luminol chemiluminescence enzyme immunoassay, which has high sensitivity, simple and quick operation, and strong specificity. When tPSA is greater than 10ng/ml, prostate cancer is highly suspected. When tPSA is between 4-10ng/ml, it is called gray value, and the diagnosis of prostate cancer should be combined with the ratio of fPSA/tPSA. 5. Bioluminescence imaging for inflammation Luminol can achieve highly sensitive bioluminescence imaging of inflammation through the luminescence reaction with myeloperoxidase MPO produced in the inflammatory area, which is important for the diagnosis of neurodegenerative diseases, atherosclerosis, cancer and other diseases significance.

Enzymes are the soul that catalyzes various reactions in nature. Many originally difficult chemical reactions can be easily handled by enzymes that are invisible to the naked eye, playing the role of superheroes in daily life. The greater the ability, the greater the responsibility; then what kind of enzyme preparation can be a superhero? The time to test them has arrived. The first level: higher specific vitality The ratio of enzyme activity to enzyme weight is called enzyme specific activity. This is a bit like a weightlifting competition. Two players with the same weight, whoever can lift a heavier weight wins. Why should we examine the specific vitality? Because the higher the specific activity, the less enzymes are needed to accomplish the same job. Enzyme itself is also a kind of protein, which can be a nutrient for microorganisms. The more enzymes also represent the more nutrients, the greater the possibility of breeding microorganisms. Therefore, the higher the specific activity of the enzyme, the lower the possibility of microbial contamination, which is vital to the stability of the catalytic reaction system. The second pass: good thermal stability Like food, enzyme preparations have a shelf life. This is because the specific activity of the enzyme preparation will slowly decrease over time, and when it drops to a certain level, the enzyme cannot continue to perform its expected function. In a high temperature environment, the enzyme activity will decrease faster. Thermal stability is an important reference for judging enzymes. Enzyme preparations with good thermal stability can withstand the toss of environmental temperature changes and have more obvious advantages in terms of validity and transportation. The third pass: a wide range of pH stability pH is a parameter describing the degree of acidity and alkalinity of the aqueous solution. Enzymes have different catalytic activities in different pH environments; enzyme preparations can maintain stable activity within a certain pH range, and over-acid or over-alkali will reduce the stability of the enzyme. If an enzyme can maintain high activity in a wide pH range, it means that the enzyme has good compatibility with catalytic reaction systems of different pH and is the first choice for consideration. Fourth hurdle: specific substrate specificity One must be dedicated to being a human being, and dedicated to doing enzymes. If an enzyme preparation is not selective to the substrate, the products of the catalytic reaction will be diverse and uncontrolled. A specific enzyme preparation will only convert substances with the same structure into products. Even if it is surrounded by other substances, it will only "love" the only substrate, and there will be no stories that shouldn't happen. The fifth level: strong anti-interference ability In the catalytic reaction system, in addition to enzymes, other substances will be added as needed; the raw materials participating in the reaction will also carry certain impurities. The appearance of these substances will affect the activity of enzyme preparations. Even with the appearance of interfering substances, excellent enzyme preparations will continue to show good vitality and continue to play a core role in inducing reactions. Enzyme preparations that can pass these five tests have the basic qualities to become a superhero. However, the distance allows these superheroes to exert their powerful catalytic ability, and there is still a long way to go. In the future, Desheng Technology will continue to introduce other knowledge about enzymes for you.

Biological buffers are an important part of electrophoresis technology and are generally added to the solution to stabilize the pH when current is passed through the sample. In addition, the buffer can also provide the ions needed for electrophoretic migration. The ideal buffer for electrophoresis depends on the isoelectric point of the sample being analyzed. Although there are many pre-made buffers for electrophoresis on the market, it is recommended to use the biological buffers prepared by yourself to make your own solutions. Our company is a professional manufacturer of biological buffers. For this reason, we have created a list of biological buffers frequently used in electrophoresis, so that it is convenient to see which biological buffer is more suitable for you. 1. Tris buffer Used for: gel electrophoresis Useful pH range: 7.5-9.0 pKa (25°C): 7.8-8.2 Molecular weight: 121.14 2. MOPS buffer Used for: gel electrophoresis Useful pH range: 6.5-7.9 pKa (25°C): 7.0-7.4 Molecular weight: 209.3 3. Bicine buffer Used for: gel electrophoresis Useful pH range: 7.6-9.0 pKa (25°C): 8.1-8.5 Molecular weight: 163.2 4. CAPS buffer Used for: Capillary Electrophoresis Useful pH range: 9.7-11.1 pKa (25°C): 10.2-10.6 Molecular weight: 221.32 5. CAPSO buffer Used for: gel electrophoresis Useful pH range: 8.9-10.3 pKa (25°C): 9.4-9.8 Molecular weight: 237.32 It can be seen from the above that there are many biological buffers used in electrophoresis, and there are some differences between them, and they can be used in different electrophoresis. In the current market, there are many vendors of biological buffers, and product specifications and quality are uneven. Our company is a manufacturer specializing in the production of biological buffers. It has been established for more than ten years and has very rich R&D and production experience and product knowledge. It can provide customers with a large amount of technical support and after-sales guarantee. Hubei Xindesheng Materials Co., Ltd. can also provide customized packaging and other services according to customer needs, and our products can be delivered to most areas at home and abroad. In addition, our company also produces blood collection tube additives, chemiluminescence reagents, chromogen substrates, carbomers and other products. If you are interested in our products, you can enter our official website to contact customer service for details.

3 - (cyclohexylamine) - 1-propanesulfonic acid (CAPS buffer) is a kind of sulfamate, cas1135-40-6. Its molecular formula is c9h19no3s, and its molecular weight is 221.32. It is white crystalline powder. Amphoteric, the most widely used is in water-based polyisocyanate coatings and buffer used in enzyme chemistry and HPLC separation of basic drugs. Desheng caps products In biological buffer: buffer for enzyme chemistry and HPLC separation of basic drugs. Product application: in biological experiments, it is an important pH stabilizing reagent, usually choose the appropriate weak acid and its conjugated base to get the appropriate pH value. Most of the biological reactions take place under neutral conditions, generally pH is between 6-8, and the effective buffer range of buffer is also between 6-8. In addition, the acid-base form of buffer should not chelate with some metal ions, such as in biochemical diagnostic kit, DNA / RNA extraction kit and PCR diagnostic kit. In the new coatings, 3 - (cyclohexylamino) - 1-propane sulfonic acid (CAPS) reacts with aliphatic polyisocyanate (the former is zwitterionic sulfamate) under mild conditions and in the presence of tertiary amine neutralizer, and the sulfonylurea derivative is an excellent emulsifier. Without considering the salt group, CAPS modified polyisocyanate has good storage stability and is not cloudy. Even if it contains less sulfonate base group, it can also get very good emulsion in water. A series of ionized polyisocyanates can be obtained, which can be used in various environment-friendly high-quality waterborne two-component polyurethane coatings. These coatings can be compared with general solvent based coatings in terms of dryness, curing and chemical resistance. In addition to the above applications, it is also a raw material for manufacturing welding materials, air conditioning equipment and lithium metal. It is also used for making pyrotechnics, analytical reagent, heat exchange carrier, pharmaceutical industry, air conditioning, pyrotechnics, dry battery and lithium metal, as well as flux and desiccant. From these applications, I can see that 3 - (cyclohexylamine) - 1-propanesulfonic acid plays an extraordinary role in our daily life. We Desheng company is to find these advantages, it has been 15 years of R & D and production, hoping to meet the needs of customers.

Desheng is a material technology company engaged in R & D, production and sales. We will make a series of comparisons for each series of products, so as to help customers better distinguish the differences between them and better find the products they need. Let's briefly describe the differences and similarities between good's buffer pipe and HEPES.   PIPES   The pH buffer range of pipes is 6.1-7.5, insoluble in water and soluble in NaOH solution. Different from buffers containing bis (2-hydroxyethyl) amino groups (such as bis Tris, bicine), pipes can not form stable complexes with most metal ions, so it is suitable for buffers containing metal ions. According to previous studies, PIPES can be used to purify tubulin by using cellulose phosphate chromatography, and to purify recombinant GTP binding protein ARF1 and ARF2 by gel filtration as a buffer to crystallize ketoenzyme from E. coli. In addition, due to the formation of free radicals, pipe is not suitable for redox system. In cation exchange chromatography, low concentration of pipes buffer should be used because of its relatively high ionic strength and concentration dependent pKa value.   HEPES   The pH buffer range of HEPES is 6.8-8.2, which is soluble in water and does not form stable complexes with metal ions. In most cases, it does not interfere with biochemical processes. HEPES is commonly used in cell culture media of various types of organisms; in protein research, it is commonly used as component and eluent of binding buffer in cation exchange chromatography; in DNA research, it is used as calcium phosphate and DN A, the buffer solution of precipitate formation system, AFM and electroporation experiment. In addition, HEPES interferes with the reaction between DNA and restriction enzyme and is not suitable for Lowry's method.   Desheng good's buffer   In conclusion, both pipes buffer and HEPES belong to good's buffer, and they can not form stable complexes with metal ions, so they are suitable for solution containing metal ions. However, there are some differences between them. In terms of solubility, pipe is insoluble in water, while HEPES has good water solubility. In terms of buffer range, pipe is acidic to neutral, and HEPES is neutral to alkaline. This is mainly due to the structural differences between them. Pipe has two sulfonic groups, and HEPES contains one sulfonic group and hydroxyl group. In addition, pipes and HEPES have some limitations in the application of some systems. Therefore, when we choose the above buffers, we need to consider the suitability of the experimental system and the difference of their properties.   When you purchase good's products, it's not the buffer you need. Desheng will also give you an accurate positioning.

I suspect that many display skills to the full play of the classic criminal investigation forensic TV series, such as forensic pioneer, legal life, and many other Hong Kong dramas. People usually suspect that they will clean up their blood after the crime and try to get more opportunities to get rid of their crimes. At this time, Luminol is the time to show his talents. The iron in blood immediately catalyzes the chemiluminescence reaction of luminol and makes it produce blue light. Because of its high efficiency and convenient use, luminol has been widely used in some criminal investigation cases.   Luminol, also known as luminol. In forensic medicine, the luminol reaction can identify blood stains that have been scrubbed for a long time. In biology, luminol is used to detect the presence of copper, iron and cyanide in cells. At room temperature is a blue crystal or pale yellow powder, is a relatively stable synthetic organic compounds. The chemical formula is c8h7n3o2.     At the same time, luminol is a kind of strong acid, which can stimulate eyes, skin and respiratory tract. Hemoglobin contains iron, which can catalyze the decomposition of hydrogen peroxide, turning hydrogen peroxide into water and monooxygen, which then oxidizes luminol to make it glow. Therefore, luminol is widely used in criminal investigation, bioengineering, chemical tracing and other fields.   Although the dosage of luminol is relatively small and it is not difficult to detect, we should pay attention to some problems when using luminol. Here are some matters needing attention when using luminol for formal investigation.   1. Luminol fluoresces in the presence of iron, ferroalloys, horseradish or some bleaching agents. So if the crime scene is completely bleached, luminol's fluorescence will strongly mask the presence of any blood stains.   2. Luminol may interfere with other tests, but luminol does not interfere with DNA extraction.   3. The use of luminol needs to be in a dark environment, which makes it easier to make a more accurate judgment with the naked eye.   4. Luminol luminescent time is limited, we should seize the time to take photos and record.   5. The illumination lasts about 30 seconds, which can be seen from long exposure photos. The surrounding environment should not be too bright.   Currently, the blood test reagent luminol produced and developed by Desheng is very mature, with the advantages of high sensitivity and high luminous efficiency. It plays an important role in criminal investigation cases, and also meets the needs of many criminal investigation enthusiasts to carry out chemiluminescence experiments by themselves. Luminol can not only be used as blood test in criminal investigation, but also can be used for chemiluminescence immunoassay.

Daos, n-ethyl-n - (2-hydroxy-3-sulfopropyl) - 3, 5-dimethoxyaniline sodium salt, the finished product is white or light blue powder, CAS number is 83777-30-4, molecular formula is c13h20nnao6s, molecular weight is 341.36, Daos is a new kind of Trinder's reagent, with high water solubility, stable reaction, wide pH range, as an excellent color reagent is widely used in diagnostic detection and biochemical experiments.   The detection principle is: in the presence of hydrogen peroxide and peroxidase, the new Trinder's reagent reacts with 4-aminoantipyrine (4-AA) or 3-methylbenzothiazolylsulfonylhydrazone (MBTH) to form a very stable purple or blue dye, and then the substrate concentration is determined by spectrophotometry.   Daos chromogenic reagent   1、 The advantages of Daos in blood glucose measurement experiment are as follows   The determination of glucose in blood is an important test item in clinical medicine. At present, the commonly used detection method is glucose oxidase coupled with peroxidase method. This method uses God to catalyze the oxidation of glucose to gluconic acid and produce H2O2. H2O2 oxidizes colorless reduced chromogen under the catalysis of pod to produce colored oxidized pigment, and then calculates the content of glucose in the sample according to the color of oxidized chromogen.   The initial reaction of this method is specific, but the indicator reaction is nonspecific. The detection performance of this method changes with the different reduction chromogens in the indicator reaction. The common reduction chromogens are linaniline (which is rarely used because it is suspected to be carcinogenic), and the improved Trinder's reagent Daos is coupled with 4-aminoantipyrine (AAP) as the reducing chromogen The maximum absorption wavelength of the oxidized pigment formed by the oxidation and condensation of Daos and AAP is 592nm. Under this wavelength, bilirubin and other substances in blood do not interfere with the absorption, which can reduce the absorption interference of bilirubin and other interfering substances on blood glucose detection.   Therefore, this method does not need to separate blood into serum, which is simpler and more accurate than the method widely used in clinical enzymatic analysis with phenol as the reduced chromogen. The linear range of glucose is 1 ~ 20mmol / L, and the recovery is 96.3% ~ 97.7%.   2、 Instruments and reagents:   UV VIS spectrophotometer, glucose oxidase, peroxidase, Daos, AAP, anhydrous glucose, citric acid and trisodium citrate dihydrate, glycerin, bovine serum albumin, blood glucose detection kit, God and pod were prepared with pH = 6 buffer solution, and other reagents were prepared with distilled water.   3、 Methods: the experiment was carried out   In 1cm cuvette, add 0.5ml (25.6u) of God, 0.5ml (11.5u) of pod, 0.1ml (1.7mmol / L) of Daos, 0.1ml (2.9mmol / L) of AAP and 0.8ml of distilled water in turn, then add 40ul (8.3mmol / L) of glucose solution, stir well and use distilled water as reference to determine the absorption spectrum.   Desheng biochemical focuses on the development and production of in vitro diagnostic reagent raw materials, mainly including blood collection additive, chemiluminescent reagent, chromogenic substrate, enzyme substrate, antigen antibody and other products. The products are widely sold in domestic and foreign markets. Desheng's goal is not to be big, but to be a strong person in the precise field of the industry and win the market trust with its own professional.

Tris, CAS: 77-86-1. It is a white crystal or powder, soluble in ethanol and water, slightly soluble in ethyl acetate and benzene, corrosive to copper and aluminum. Tris base has high buffer capacity, high solubility in water and is inert to many enzyme reactions, which makes Tris a very satisfactory buffer for many biochemical purposes. It is used to stabilize the pH of the reaction system and has a strong buffer capacity between pH 7.5 and 9.0.   Desheng Tris packaging   Tris in glyphic acid buffer system was used to stabilize pH value in the electrophoretic buffer solution. The Tris-HCl buffer system was used to stabilize pH value in the gel. It was widely used as a solvent for nucleic acids and proteins. The low ionic strength of Tris buffer could also be applied to the formation of intermediate fibers of nematodes. EDTA buffer was added into Tris hydrochloric buffer to make TE buffer, which could be used for the stabilization and storage of DNA. The "Tae buffer" can be obtained by replacing the acid solution with acetic acid, and tbe buffer can be obtained by replacing it with boric acid. These two buffers are often used in nucleic acid electrophoresis experiments.   Tris is used in both TAE and tbe buffer (for nucleic acid dissolution) in biochemical experiments. It contains amino groups and can react with aldehydes. Tris is a weak base and its PKA is 8.1 at 25 ℃. The effective buffer range of Tris buffer is between pH 7.0 and 9.2.   The pH value of Tris base aqueous solution is about 10.5. Generally, hydrochloric acid is added to adjust the pH value to the desired value to obtain the buffer solution with this pH value. At the same time, we should pay attention to the effect of temperature on pKa of Tris. 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 for DNA stabilization and storage. If the acid solution of adjusting pH value is replaced by acetic acid, the "Tae buffer" (Tris / acetate / EDTA) is obtained, and the "tbe buffer" (Tris / borate / EDTA) is obtained by replacing it with boric acid. These two buffers are usually used in nucleic acid electrophoresis experiments.   TAE and tbe made from Tris are commonly used in DNA electrophoresis. Te (ph8.0) is mainly used to dissolve DNA. (TE is Tris plus EDTA.) 1mtris-hcl6.8 and 1.5mtris-hcl8.8 are commonly used in SDS-PAGE. Tris buffer has been used more and more in biochemical research, with the trend of more than phosphate buffer. Tris buffer has been used in SDS- polyacrylamide gel electrophoresis, and phosphate is rarely used. The common effective pH range of Tris buffer is in the "neutral" range.   In Tris medium, a certain microorganism can produce certain metabolites after growing in the medium, which can react with special chemicals in the medium and produce obvious characteristic changes. According to this characteristic change, this kind of microorganism can be distinguished from other microorganisms   In Tris HC, an amino group in it is a coordination group, which may replace the ligand in the original complex, thus changing the complex and affecting the absorbance. If you want to know whether there will be such an effect, you need to check their coordination constants and compare them.   Desheng has 15 years of experience in R & D and sales of biological buffers, and has generally received high praise from customers. There is still a long way to go in the future, and we will make persistent efforts to forge ahead!