| Description | In the experimental process of molecular biology, Fluo ™ Green ® The dsDNA quantification kit is a product used for fluorescence detection and quantification of double stranded DNAThe method is very sensitive. Commonly used in molecular biology techniques: construction of cDNA libraries; In the experimental process of molecular biology, Fluo ™ Green ® The dsDNA quantification kit is a product used for fluorescence detection and quantification of double stranded DNAThe method is very sensitive. Commonly used in molecular biology techniques: construction of cDNA libraries; Purification and application of DNA fragments for subcloning, such as DNA quantification, product amplification, and further detection of primers. Vaccines are a commonly used control method in modern disease prevention. Nowadays, many vaccines are cell culture vaccines, such as recombinant hepatitis B vaccine, rabies vaccine and most other vaccines are produced by cell culture. Among them, the purification of vaccines is a key issue, and we need to remove host cell DNA and host proteins as much as possible. If the DNA and protein of the host cell are injected into the human body together with the vaccine, unpredictable consequences will occur.The conventional method for detecting DNA content is to measure its absorbance at 260nm (A260). The main disadvantage of this method is that nucleotides, single stranded nucleic acids, and proteins have a significant impact on the signal, and are also subject to interference from pollutants during the nucleic acid preparation process, making it difficult to distinguish between DNA and RNA. Additionally, this method is insensitive (5 µ g/mL dsDNA solution A260=0.1). Fluo ™ The Green quantitative detection method is simple and convenient, and has been selected by multiple biological product factories, becoming the standard for residual DNA detection in biological products.At present, this method has been included in the 2010 edition of the Chinese PharmacopoeiaPrinciple:Fluo ™ Green emits fluorescence only after binding to double stranded DNA, and does not emit fluorescence without DNA; The fluorescence emitted is directly proportional to the concentration of DNA. In the 2010 Chinese Pharmacopoeia, it was proposed that, Fluo ™ The detection limit of Green's quantitative DNA method is about 0.3ng/ml, and the linearity is good (R2>0.99) when the DNA content is in the range of 1.25-80ng/mLAdvantage:1) This method can determine double stranded DNA from any expressed host sample.2) It is possible to directly quantify PCR amplification products without purifying DNA from the reaction mixture.3) Far exceeding the sensitivity of traditional UV A260 detection methods and Hoechst33258.4) Higher concentrations of salt, urea, ethanol, chloroform, detergents, proteins, or agarose have no effect on the measurement.5) The effect of measuring dsDNA in the presence of equimolar concentrations of ssDNA and RNA is minimal.Required equipment• Micro fluorescence meter; Portable fluorescence analyzer - Shanghai Huguo Scientific Instrument Co., Ltd. HG-9 model; 1cm quartz colorimetric dish• Fluo ™ Green dsDNA quantitative detection kit, 1mL of concentrated reagent solution is sufficient for 200 measurements of 2mL volume.1×TE（10mM Tris 1mM EDTA）pH8.0； 250ug/mL calf thymus DNAExperimental planPreparation of reagentsFluo ™ The Green dsDNA quantification reagent is stored in anhydrous DMSO (dimethyl sulfoxide) in the form of 1mL concentrated solution. On the day of the experiment, prepare2X Fluo ™ The operating solution of Green's reagent was diluted with 1xTE at a ratio of 1:200 in concentrated solution (10mM Tris HCl,1mM EDTA, pH 7.5). If you want to prepare enough operating solution to determine 20 samples, you can add 100 µ L Fluo to 20mL1x TE ™ Green dsDNA quantification reagent. Due to the easy adsorption of reagents onto glass surfaces, they need to be prepared in plastic containers. Fluo ™ Green reagent is easily degraded by light, so the prepared solution should be wrapped in foil or stored in a dark place away from light.It is best to use the solution within a few hours of preparation to ensure optimal results.Experimental method:1). Preparation of standard working fluid:1mg of calf thymidine DNA dry powder (Tris, NaCl, and other concentrations have become standard systems) is added to 1mL of double distilled water to prepare a 1mg/mL standard working solution;2). Configuration of dye working fluid:6 uL Fluo ™ Add 1mL of TE to Green (note: use 1 × TE to mix Fluo) ™ Dilute Green 200 times, use and prepare immediately, avoid light.3). Dilution of standard working fluid:(1) Mother liquor dilution: Take 10ul (1mg ⁄ mL) of standard working solution and add it to 990ul TE solution to dilute the concentration to 10ug ⁄ mL. Take 10ul (10ug ⁄ mL) of standard working solution and add it to 990ul TE solution to dilute the concentration to 100ng ⁄ mL;(2) Dilute by multiple ratio: Take 800ul (100ng ⁄ mL) of standard working solution and add it to 200ul of TE solution to achieve a concentration of 80ng ⁄ mL (pharmacopoeia regulation: fluorescent)The light staining method shows good linearity in the range of 1.25-80 ng/mL for DNA content, with a detection limit of 0.3 ng/mL. Take 500ul (80ng ⁄ mL) of standard working solution and add it to 500ul TE solution, diluting the concentration to 40ng ⁄ mL; Dilute sequentially by multiple ratios to prepare 20ng/ml 10ng/ml 5.0ng/ml 2.5ng/ml1.25ng/ml and 0.625ng/ml standard solution;4). Preparation of standard curve: Take 100ul of each gradient standard solution and dye working solution diluted by multiple ratios, mix well, and leave them at room temperature in the dark for 5 minutes. Use FB-15 portable fluorescence analyzer to detect the fluorescence value of the sample: Add the mixed solution to the microcalorimeter, make sure not to introduce bubbles into the sample, and gently tap the outside of the microcalorimeter to disperse the bubbles. Measure the fluorescence values of the sample and blank control using 1 × TE buffer as a blank; Corresponding to the concentration of standard solution (ng/ml)Perform linear regression on fluorescence intensity and prepare a standard curve.5). Measure the fluorescence value of the remaining samples. The fluorescence meter will provide a direct concentration reading, which can be used to generate a standard curve of DNA concentration. Final concentration of DNA to be tested Fluorescence reading value (ng/ml) / 100 6210 50 3195 40 2507 20 1261 10 620.8 5 298 4 258.8 2 152 0.5 43.8 0 0.72... Read More | Product content: M665794Component125 TStorageM665794A2×miRNA qPCR Mixture (ROX)2×750 µL-20℃. Avoid freeze/thaw cycleM665794BReverse Primer, 10 µM60 µL-20℃. Avoid freeze/thaw cycleM665794CddH2O1.5 mL-20℃. Avoid freeze/thaw cycle Product Introduction:This kitProduct content: M665794Component125 TStorageM665794A2×miRNA qPCR Mixture (ROX)2×750 µL-20℃. Avoid freeze/thaw cycleM665794BReverse Primer, 10 µM60 µL-20℃. Avoid freeze/thaw cycleM665794CddH2O1.5 mL-20℃. Avoid freeze/thaw cycle Product Introduction:This kit uses the principle of SYBR Green I chimeric fluorescent dye method for miRNA fluorescence quantitative PCR detection. The kit includes 2 x miRNA qPCR Mixture and Reverse Primer required for detection. 2 x miRNA qPCR Mixture is a new generation pre mixed form of fluorescence quantitative PCR detection reagent specially developed for miRNA quantitative detection. The fluorescent dye SYBR Green I contained in it can bind to all double stranded DNA, making the product suitable for detecting different target sequences without the need to synthesize specific labeled probes. The GoldStar Taq DNA polymerase is a chemically modified and highly efficient thermal starter enzyme, coupled with a unique buffer system, which enhances reaction specificity, sensitivity, and enables accurate quantification of miRNA over a wider range. The 2x miRNA qPCR Mixture contains ROX dye and is suitable for fluorescence quantitative PCR instruments that require ROX as a calibration dye.Note: This kit must be used in conjunction with the miRNA cDNA first strand synthesis kit.Self prepared experimental materials: qPCR upstream primer.Forward Primer design principles:1. Follow the most common principles of primer design.2.Based on mature miRNA sequences, replacing U with T is the most basic and simplest design method.3.The Tm value of the downstream primer provided in the reagent kit is 63.6 ℃, and the Tm value of the upstream primer should be designed to be around 63.6 ℃ as much as possible.4. If the Tm value of the primer directly designed according to principle "2" is too low, several bases (preferably G or C bases) can be added to the 5 'end of the primer; One or several A bases can also be added at the 3 'end; Alternatively, both the 5 'and 3' ends can be modified simultaneously.5.If the Tm value of a primer designed directly according to principle "2" is too high, several bases can be removed from the 5 'or 3' end of the primer.Notes:1. Before using the reagent, please gently mix it upside down to avoid foaming, and use it after a brief centrifugation.2. The amount of miRNA first strand cDNA added should not exceed 10% of the volume of Real time PCR.3. For special detection systems, high content of cDNA templates can easily lead to non-specific amplification. Dilute cDNA appropriately (10 or 100 times dilution) based on the abundance of detected miRNAs.4. The 2x miRNA qPCR Mixture in this product contains SYBR Green I and ROX dyes. When storing this product or preparing PCR reaction solution, strong light exposure should be avoided.5. Avoid repeated freezing and thawing of this product. Repeated freezing and thawing may cause a decrease in product performance. This product can be stored at -20 ℃ for long-term storage. If frequent use is required in the short term, the 2xmiRNA qPCR Mixture can be stored at 2-8 ℃. However, the Reverse primer still needs to be stored at -20 ℃.Operation steps:1. Melt 2 x miRNA qPCR Mixture and Reverse Primer at room temperature (10 µ M). 2. When using, please gently mix the 2x miRNA qPCR Mixture upside down to avoid foaming, and use after brief centrifugation. If the reagent is not well mixed, its reaction performance will decrease.3. Place the reagent on ice and prepare the reaction system according to the following table: reagent volume final concentration 2×miRNA qPCR Mixture（ROX） 10 µl 1× Forward primer（10 µM） 0.4µl 0.2 µM Reverse primer（10 µM） 0.4µl 0.2 µM MiRNA first strand cDNA X µl — ddH2O up to 20 µl —4. The reaction program is set as follows:Attention!The pre denaturation reaction of this product must be completed at 95 ℃ for 10 minutes! Note: 1) The hot start enzyme used in this product must be activated under pre denaturation conditions of 95 ℃ and 10 minutes.2) The annealing temperature should be set at 60-64 ℃ as a reference range. When non-specific reactions occur, the annealing temperature can be increased... Read More | Product introduction：Griess reagent can be used for spectrophotometric detection of nitrite. The reagent contains two chemicals, sulfonic acid and n- (1-naphthyl) ethylenediamine. Under acidic conditions, sulfamic acid is converted into diazonium salt by nitrite, which can form a highly Product introduction：Griess reagent can be used for spectrophotometric detection of nitrite. The reagent contains two chemicals, sulfonic acid and n- (1-naphthyl) ethylenediamine. Under acidic conditions, sulfamic acid is converted into diazonium salt by nitrite, which can form a highly colored azo dye with n- (1-naphthyl) ethylenediamine. This dye can be detected at 548 nm: because no is extremely unstable, it is oxidized to form nitrite and nitrate. Griess indirectly reflects the content of no by detecting the content of nitrite.Matters needing attention：1. before using Griess reagent, return it to room temperature and check the solution for precipitation. If Griess reagent I contains sediment when taken out, it can be placed in a 37 ℃ water bath until the sediment dissolves. 2. this product is potentially harmful. Avoid prolonged or repeated exposure. Avoid entering eyes, skin or clothing. Please wear lab clothes and disposable gloves for operation.Scope of application：No detectionComponent：Instruction：1.Griess Reagent I and II were taken out to restore the room temperature.2.Standard dilution : The standard NaNO2 ( 1-100 µM ) was diluted with the solution used for the sample to be tested. The standard was diluted to 1 µM, 10 µM, 20 µM, 40 µM, 80 µM and 100 µM, and 100 µL standard was added to each well. If the sample concentration is too low, the range of the standard curve can be appropriately reduced ( 1 µM, 2 µM, 3 µM, 4 µM, 6 µM, 8 µM, 10 µM ).3.Sample detection :( 1 ) According to the total volume of 200 µL / hole, 100 µL / hole sample was added to the 96-well plate ; if the sample is the supernatant of the culture medium, it can be sampled directly, and if there is sediment, the supernatant should be taken after centrifugation. If the sample is a cell or tissue, it can be quickly lysed by freeze-thaw, and then centrifuged to obtain the supernatant. The volume of less than 100 µL can be diluted with diH2O or 0.9 % NaCl ( corresponding standards also need to be diluted with diH2O or 0.9 % NaCl ).( 2 ) According to 50 µL / hole, Griess Reagent I was added to each hole.( 3 ) According to 50 µL / hole, Griess Reagent II was added to each hole.( 4 ) The absorbance was measured at 540 nm. If there is no 540 nm filter, 520-560 nm filter can also be. If there is no microplate reader or a suitable filter, the concentration of nitric oxide in the sample can also be determined by visual colorimetry. A more precise concentration gradient is required for the standard when visual colorimetric... Read More | Product contentS665868Component50 TStorageS665868ABuffer GL25 mLRTS665868BBuffer GW1 (concentrate)13 mLRTS665868CBuffer GW2 (concentrate)15 mLRTS665868DBuffer GE15 mLRTS665868EProteinase K2×1.25 mLRTS665868FSpin Columns DM with Collection Tubes50 setsRTProduct IntroductionThis kit is suitable Product contentS665868Component50 TStorageS665868ABuffer GL25 mLRTS665868BBuffer GW1 (concentrate)13 mLRTS665868CBuffer GW2 (concentrate)15 mLRTS665868DBuffer GE15 mLRTS665868EProteinase K2×1.25 mLRTS665868FSpin Columns DM with Collection Tubes50 setsRTProduct IntroductionThis kit is suitable for the extraction of genomic DNA from fresh saliva or saliva/preservation solution mixture.The purification process of this product does not require the use of toxic solvents such as phenol or chloroform, and ethanol precipitation is not necessary. The optimized buffer system enables DNA to bind heterogeneously to the silica matrix centrifugal adsorption column, and the inhibitors of PCR and other enzymatic reactions can be effectively removed by a two-step washing step, and finally eluted with a low-salt buffer or water to obtain high-purity DNA.The purified obtained can be directly used for enzyme digestion, PCR, Real-Time PCR, library construction, Southern Blot, molecular labeling and other downstream experiments.Self-contained reagent: anhydrous ethanolPre-experiment Preparation and Important Notes1. Repeated freezing and thawing of the sample should be avoided, as this may result in smaller fragments of extracted DNA and a decrease in the amount extracted.2. Anhydrous ethanol should be added to Buffer GW1 and Buffer GW2 according to the instructions on the label of the reagent bottle before first use.3. Before use, please check whether Buffer GL appears to be crystallized or precipitated.Redissolve in a 56°C water bath.4. If the downstream experiments are sensitive to RNA contamination, 4 µL DNase-Free RNase A can be added in step 3(100 mg/mL).5. For prolonged storage of salivary DNA at room temperature, our Salivary DNA Preservation Tubes are recommended.Operation steps1. Add 400 µL of saliva sample or saliva/preservation solution mixture.Note: 1) Saliva mixtures added to the preservation solution require a 50°C water bath for 1 hour or an empty 50°C temperature chamber for 2 hours prior to extraction.2) If an increase in sample volume is required, multiply the volumes of Proteinase K, Buffer GL, and anhydrous ethanol in Steps 2-4, and the liquid can be transferred in multiple times in Step 5.2. Add 40 µL of Proteinase K.3. Add 400µL Buffer GL, vortex and shake to mix thoroughly, and water bath at 56℃ for 15-30 minutes.Note: If RNA removal is required, add 4 µL of RNase A solution at a concentration of 100 mg/mL after the above steps are completed, vortex for 15 seconds, and leave at room temperature for 2 minutes.4. Centrifuge briefly to remove water droplets from the inside of the tube cap. Add 400 µL of anhydrous ethanol and mix well by vortexing and shaking. Centrifuge briefly.Note: 1) Vortex and shake to mix immediately after adding Buffer GL and anhydrous ethanol.The addition of Buffer GL and anhydrous ethanol may produce a white precipitate that will not affect subsequent experiments.2) A sol-gel product may be formed after GL and anhydrous ethanol, in which case vigorous shaking or vortexing is recommended.3) The solution obtained in the previous step is added to the adsorption column in the Collection Tube.5. (Spin Column DM) in the collection tube, and if the solution cannot be added all at once, it can be transferred in several times. centrifuge at 12,000 rpm (∼13,400 × g) for 1 min, pour off the waste solution in the collection tube, and put the adsorption column back into the collection tube.6. Add 500 µL of Buffer GW1 to the adsorption column (check that anhydrous ethanol has been added before use), centrifuge at 12,000 rpm for 1 minute, pour off the waste liquid in the collection tube, and put the adsorption column back into the collection tube.7. Add 500 µL of Buffer GW2 to the adsorption column (check that anhydrous ethanol has been added before use), centrifuge at 12,000 rpm for 1 minute, pour off the waste liquid in the collection tube, and put the adsorption column back into the collection tube.Note: Step 7 can be repeated if further DNA purity is required.8. Centrifuge at 12,000 rpm for 2 minutes and pour off the waste liquid in the collection tube. Leave the adsorption column at room temperature for several minutes to dry thoroughly.Note: The purpose of this step is to remove residual ethanol from the adsorption column, which can interfere with subsequent enzymatic reactions (digestion, PCR, etc.).9. Place the adsorption column in a new centrifuge tube (supplied), add 50-200 µL of Buffer GE or sterilized water to the middle of the adsorption column overhanging the column, let it stand at room temperature for 2-5 minutes, and centrifuge at 12,000 rpm for 1 minute to collect the DNA solution.-20°C to preserve DNA.Note: 1) If the downstream experiment is sensitive to pH or EDTA, you can use sterilized water for elution. The pH of the eluent has a great influence on the elution efficiency, if water is used as the eluent should ensure that its pH is 7.0-8.5 (you can use NaOH to adjust the pH of the water to this range), and the elution efficiency is not high when the pH is lower than 7.0.2) Buffer GE preheated in a 65-70°C water bath and incubated at room temperature for 5 min before centrifugation can increase the yield.3) Because DNA preserved in water is subject to acidic hydrolysis, for long-term storage, elution with Buffer GE and storage at -20°C is recommended... Read More | Product content： Component S665549 50 preps Buffer SW 60 ml Buffer SL 60 ml Buffer GL 50 ml Buffer GW1（concentrate） 2X13 ml Buffer GW2（concentrate） 15 ml Buffer GE 15 ml Spin Columns DM 50 with Collection Tubes 50Product IntroductionThis kit is suitable for Product content： Component S665549 50 preps Buffer SW 60 ml Buffer SL 60 ml Buffer GL 50 ml Buffer GW1（concentrate） 2X13 ml Buffer GW2（concentrate） 15 ml Buffer GE 15 ml Spin Columns DM 50 with Collection Tubes 50Product IntroductionThis kit is suitable for extracting total DNA from fecal samples, including the total DNA of cells, bacteria, parasites, and viruses in the samples, as well as samples containing high concentrations of PCR reaction inhibitors. This product can process up to 300 mg of fecal samples and purify to obtain mainly 20-30 kb DNA fragments. The purification process does not require toxic solvents such as phenol or chloroform, and does not require ethanol precipitation. High purity DNA can be obtained within one hour. This reagent kit adopts a unique buffering system to efficiently bind DNA from the lysis solution to the adsorption column. At the same time, protein impurities and other organic compounds that inhibit downstream reactions in feces can flow through the membrane. Inhibitors of PCR and enzyme reactions, as well as residual impurities, can be effectively removed through two washing steps. Finally, high-purity DNA can be obtained by washing with low salt buffer or water. The purified DNA can be directly used for downstream experiments such as enzyme digestion, PCR, Real Time PCR, library construction, Southern Blot, and molecular labeling.Preparation and important precautions before the experiment1. Samples should avoid repeated freeze-thaw cycles, otherwise it may result in smaller extracted DNA fragments and a decrease in extraction volume.2.Before the first use, anhydrous ethanol should be added to Buffer GW1 and GW2 according to the instructions on the reagent bottle label.3. Before use, please check whether there is crystallization or precipitation in Buffer SL and Buffer GL. If there is crystallization or precipitation, please dissolve Buffer SL and Buffer GL again in a 56 ℃ water bath.4. If downstream experiments are sensitive to RNA contamination, 4 can be added after adding Buffer SL µ RNase A of DNase Free (100 mg/ml) is not provided in this kit. If needed, it can be ordered separately from our company, item number: S665549Operation steps1. Take a fecal sample of 100-300 mg and place it in a centrifuge tube (provided by oneself).2. Add 1 ml of Buffer SW and vortex for 3-5 minutes to evenly disperse the sample in the solution. Centrifuge at 12000 rpm (~13400 × g) for 1 minute and discard the supernatant.3. Add 1 ml of Buffer SL and vortex for 3-5 minutes to evenly disperse the sample in the solution. Take a water bath at 65 ℃ for 20 minutes and vortex for 15 seconds every 5 minutes. Note: To remove RNA, add 4 after completing the above steps µ RNase A solution (product number: CW0601S) with a concentration of 100 mg/ml, shake well and let stand at room temperature for 5-10 minutes.4.Centrifuge at 2000 rpm for 3 minutes and transfer the supernatant to a new centrifuge tube (provided by oneself).5. Add an equal volume of Buffer GL to the supernatant, invert and mix 15-25 times, and leave on ice for 5 minutes. Centrifuge at 12000 rpm for 5 minutes. Attention: At this time, the liquid may be in a transparent or turbid state, which does not affect the experiment. 6. Add the supernatant obtained in step 5 to the spin columns DM that have been loaded into the collection tube. If the solution cannot be added at once, it can be transferred multiple times. Centrifuge at 12000 rpm (~13400 × g) for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.7. Add 500 to the adsorption column µ Buffer GW1 (check if anhydrous ethanol has been added before use), centrifuge at 12000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube. 8. Repeat step 7.9. Add 500 to the adsorption column µ Buffer GW2 (check if anhydrous ethanol has been added before use), centrifuge at 12000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.10.12000 rpm for 2 minutes and discard the waste liquid from the collection tube. Place the adsorption column at room temperature for a few minutes to thoroughly air dry. Note: The purpose of this step is to remove residual ethanol from the adsorption column, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).11. Place the adsorption column in a new centrifuge tube (self provided) and add 50-100 drops of suspended droplets to the middle of the adsorption column µ L Buffer GE or sterilized water, leave at room temperature for 2-5 minutes, centrifuge at 12000 rpm for 1 minute, collect DNA solution, and store DNA at -20 ℃.Note: 1) If downstream experiments are sensitive to pH or EDTA, they can be washed off with sterilized water. The pH value of the eluent has a significant impact on the elution efficiency. If water is used as the eluent, its pH value should be ensured to be between 7.0-8.5 (NaOH can be used to adjust the pH value of the water to this range). When the pH value is below 7.0, the elution efficiency will be reduced2) Incubating at room temperature for 5 minutes before centrifugation can increase yield.3) Use an additional 50-100 µ Further washing with buffer GE or sterilized water can increase yield.4) If you want to increase the final concentration of DNA, you can add the DNA eluent obtained in step 11 back onto the adsorption membrane and repeat step 11; It is possible to increase the final concentration of DNA, but it may reduce the total yield. If the amount of DNA is less than 1 µ g. Recommended 50 µ Wash with buffer GE or sterilized water.5) DNA stored in water can be affected by acidic hydrolysis. If long-term storage is required, it is recommended to elute with Buffer GE and store at -20 ℃.6) The residual trace PCR inhibitors in the genomic DNA template may have adverse effects on the PCR reaction, which can be solved by diluting DNA by 2-10 times... Read More |