| 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 | Inquire | The commonly used method of eukarYOtic gene expression regulation research is the detection of reporter genes, and bioluminescence is the most commonly used and effective means of reporter gene detection. Luciferase can catalyze the conversion of the substrate luciferin and emit photons. This The commonly used method of eukarYOtic gene expression regulation research is the detection of reporter genes, and bioluminescence is the most commonly used and effective means of reporter gene detection. Luciferase can catalyze the conversion of the substrate luciferin and emit photons. This product provides a rapid, sensitive and stable detection method for the expression of Renilla luciferase reporter gene in mammalian cells. Product characteristic：1.Rapid : Cell lysis was completed within 10-15 min ；2.Convenience : The reagent is easy to prepare, and the sample detection steps are simple；Instruction：1. Cell lysis ( 1 ) Remove the culture medium and gently wash with PBS ( adherent cells can be directly performed this operation, suspension cells should be centrifuged to collect cells ). Add 1 × Lysis Buffer ( diluted component A with sterile water at 4 : 1 ) according to the following scheme, and then place the culture plate on a micro-oscillator at room temperature for 15 min to fully lyse the cells. Note : The pyrolysis products can be stored at room temperature for 6 h, and can be stored at − 70 °C for a long time ( the pyrolysis products cannot be repeatedly frozen and thawed ). ( 2 ) The pyrolysis products after full pyrolysis were centrifuged at 10000-15000 rpm for 3-5 min. After centrifugation, the supernatant was moved into a new EP tube for subsequent detection. 2. Preparation of working fluid ( 1 ) Restore all components to room temperature. ( 2 ) Dilute component C into renilla luciferase working solution with component B, and the dilution method is to add 1 µL C component to 49 µL B component. 3.chemiluminescence value detection ( 1 ) According to the operation instructions of the instrument, the instrument with chemiluminescence detection function was opened, such as multifunctional microplate reader. The parameters were set, the determination time was 10 s, and the determination interval was 2 s. ( 2 ) The cell lysis products were added to the measuring tube according to the volume of 20 ~ 100 µL ( keep the same amount of samples each time ). 1 × Lysis Buffer was blank control. ( 3 ) 100 µL renilla luciferase working solution was added to determine the RLU ( Relative light unit ) value ( Shaking mixing function is recommended for microplate reader ). Note : The renilla luciferase working solution cannot be stored for a long time. It is now ready for use and is used once. Component：RenillaLuciferase Lysis Buffer；RenillaLuciferase Assay Buffer；CoelenterazineMatters needing attention：Scope of application： Matters needing attention：1.Please instantaneously centrifuge the product to the bottom of the tube before use, and then carry out subsequent experiments ; 2.Due to the influence of temperature on the enzyme reaction, the sample and reagent should be measured after reaching room temperature. 3.The strongest wavelength of bioluminescence catalyzed by renilla luciferase is 480 nm, in order to prevent interference between holes, it is recommended to use white opaque orifice plate ;4. B component is recommended to carry out small batch packing according to the experimental requirements ; 5.It is recommended to use it now to avoid repeated freezing and thawing ; 6.For your safety and health, please wear experimental clothes and wear disposable gloves. Scope of application：Study on gene expression regulation and promoter... Read More | Product content: S665546Component50 TStorageS665546ABuffer QSL45 mLRTS665546BBuffer RIL11 mL2-8℃S665546CBuffer ML10 mLRTS665546DBuffer GW1 (concentrate)13 mLRTS665546EBuffer GW2 (concentrate)26 mLRTS665546FBuffer EBL13 mLRTS665546GRNase A240 µLRTS665546HLysis Tubes Ⅱ50 Product content: S665546Component50 TStorageS665546ABuffer QSL45 mLRTS665546BBuffer RIL11 mL2-8℃S665546CBuffer ML10 mLRTS665546DBuffer GW1 (concentrate)13 mLRTS665546EBuffer GW2 (concentrate)26 mLRTS665546FBuffer EBL13 mLRTS665546GRNase A240 µLRTS665546HLysis Tubes Ⅱ50 EARTS665546ISpin Columns DM With Collection Tubes50 EARTProduct IntroductionThis kit provides a method for extracting total DNA from soil or fecal samples, including the total DNA of cells, bacteria, parasites, and viruses in the samples. It is also suitable for extracting DNA from samples containing high concentrations of PCR reaction inhibitors. This reagent kit adopts a unique buffering system to efficiently bind DNA from the lysis solution to the adsorption column. Inhibitors of PCR and enzyme reactions, as well as residual impurities, can be effectively removed through 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 second-generation sequencing (16S amplicons and metagenomes), library construction, PCR, qPCR, Southern Blot, enzyme digestion molecular markers, etc.Self prepared reagents1. Constant temperature mixer - Product number: CW25932. Anhydrous ethanol, isopropanol3. Vortex oscillator or tissue grinderPreparation 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 (concentrate) and Buffer GW2 (concentrate) according to the instructions on the reagent bottle label.3. Take out the buffer RIL before use and store it at 2-8 ℃ immediately after use.Operation steps1. Centrifuge the Lysis Tube briefly to allow the beads to settle at the bottom.2. a. Add 0.1-0.3 g of soil or fecal sample to Lysis Tube, and add 740-820 µ L Buffer QSL and 4 µ L RNase A, tighten the tube cover and briefly vortex to mix.b. If fecal samples are stored in non lytic fecal preservation solutions (such as CWY041S and CWY041M), add 200 to Lysis Tube µ L-600 µ L solid-liquid mixture, centrifuge at 13000 rpm for 1 minute, discard the storage solution (if the amount of solid after centrifugation is too small, it can be enriched again, but should not exceed 0.3g). Join 620 µ LBuffer QSL and 4 µ L RNase A, tighten the tube cover and briefly vortex to mix.3. Fix the Lysis Tube in an oscillating grinding device equipped with a 2 mL adapter and process it according to the optimized grinding conditions of your equipment (see appendix).4. Shake the Lysis Tube on a constant temperature mixer at 70 ℃ and 1200 rpm for 10 minutes. Subsequently, centrifuge at 13000 rpm for 2 minutes to precipitate solid particles. Transfer 540 µ Transfer the supernatant to a new 2 mL centrifuge tube.5. Add 180 µ L Buffer RIL, vortex for 5 seconds, centrifuge at 13000 rpm for 2 minutes.Attention: Remove the buffer RIL before use and store it at 2-8 ℃ immediately after use.6. Add 160 to the new centrifuge tube in sequence µ L Buffer ML, 480 µ Supernatant from step 5, 320 µ L isopropanol, vortex for 5 seconds.7. Transfer the solution from the previous step to 650 µ Centrifuge at 12000 rpm (~13400 × g) for 1 minute into the spin columns DM that have been loaded into the collection tube.8. Discard the waste liquid in the collection pipe and place the adsorption column back into the collection pipe. Repeat step 7 until all the solution has been transferred.9. Add 500 to the adsorption column µ L 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.10. Add 500 to the adsorption column µ L 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. 11. Repeat step 10.12.12000 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.).13. Place the adsorption column in a new centrifuge tube (self provided) and add 50-200 drops of suspended droplets to the middle of the adsorption column µ L Buffer EBL 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) Incubating at room temperature for 5 minutes before centrifugation can increase yield.2) Use an additional 50-100 µ Further elution with L buffer or sterilized water can increase yield.3) If you want to increase the final concentration of DNA, you can add the DNA eluent obtained in step 13 back onto the adsorption membrane and repeat step 13, but it may reduce the total yield.4) The elution buffer does not contain chelating agents, please store DNA at -20 ℃.5) The residual trace PCR inhibitors in the genomic DNA template may have adverse effects on the PCR reaction, which can usually be resolved by diluting the DNA by 2-10 times.Appendix: Grind the sample using one of the following methods1. Manually vortex oscillate at maximum speed on the vortex oscillator for 10 minutes.2. On a vortex oscillator equipped with a 1.5-2 mL horizontal centrifuge tube holder, oscillate at maximum speed for 10 minutes (keeping the Lysis Tube horizontal). If the sample size exceeds 12, extend by 5-10 minutes. For example, using Scientific Industries or Mobile's Vortex Genie2 vortex oscillator.3.When using Qiagen's TissueLyser II, grind at 25Hz for 10 minutes.4.When using Qiagen's PowerLyzer 24 Homogenizer, homogenize at 2000 rpm for 30 seconds, pause for 30 seconds, and then homogenize again at 2000 rpm for 30 seconds.5.When using FastPrep-24 from MP Biomedicals, the recommended speed is 6.0 and the time is 40 seconds... Read More | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export |