| Description | Inquire | CFDASE cell proliferation and tracking detection kit is a kit for cell proliferation and tracking detection based on CFDA se. This kit is composed of CFDASE powder, solvent and staining buffer. CFDASE is a derivative of fluorescein diacetate (FDA), which has cell membrane permeability and CFDASE cell proliferation and tracking detection kit is a kit for cell proliferation and tracking detection based on CFDA se. This kit is composed of CFDASE powder, solvent and staining buffer. CFDASE is a derivative of fluorescein diacetate (FDA), which has cell membrane permeability and does not have fluorescence luminescence. When CFDASE penetrates the cell membrane into living cells, it can be catalysed by esterases in the cytosol to produce carboxyfluorescein succinimidyl ester (CFSE), which can emit strong green fluorescence, cannot penetrate the cell membrane, and can remain intact in the cell. CFSE can also spontaneously and irreversibly covalently bind to intracellular amino groups to couple to cellular proteins. Meanwhile, the excess and uncoupled CFDASE returned to the extracellular medium by passive diffusion and was cleared by subsequent washing steps. The fluorescence of non dividing cells labeled by CFDASE is very stable, and the stable labeling time can reach several months, so it is very suitable for cell community analysis. The fluorescence of CFDASE labeled cells is very homogeneous, which is superior to other cell tracking fluorescent probes used previously, such as PKH26, and the fluorescence distribution of the divided progeny cells is also very uniform. In the process of cell division and proliferation, CFSE labeled fluorescence can be evenly distributed to the two progeny cells, and the fluorescence intensity becomes half of the parental cells. According to the fluorescence intensity, flow cytometer (FL1 channel) can detect undivided cells, cells that divide once (1 / 2 of the fluorescence intensity), twice (1 / 4 of the fluorescence intensity), three times (1 / 8 of the fluorescence intensity), and cells that divide more times. CFDASE can detect up to eight or more cleavages. CFDASE labeled cells can be used for proliferation studies in vitro and in vivo, and have the function of not staining adjacent cells. CFDASE is most commonly used to detect the proliferation of lymphocytes, and can also be used to detect the proliferation of fibroblasts, NK cells and other cells. CFDASE labeled cells showed green fluorescence. In addition to flow cytometry to detect cell proliferation, fluorescence microscopy can also be used for homogeneous staining of cell tracking observation.Components:ComponentsC598182-20TC598182-500TA. CFDA SE1 tube1 tubex5B.CFDA SE solvent20 µL500 µLC.10x CFDA SE Buffer1 mL x250 mLMatters needing attention:1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. CFDA and Se are easily hydrolyzed and will deteriorate quickly in aqueous solution. Please avoid contact with water during use. Contact with water during the process of labeling cells is within the permitted range. 3. CFDA se solvent will solidify at lower temperatures such as 4 º C and ice bath and stick to the bottom, wall or cover of the centrifugal tube. It can be used after incubating in a 20-25 º C water bath for a while until it is completely dissolved. 4. this kit optimizes the CFDA se staining system, but users are advised to explore the optimal working concentration and staining time according to their own cell type, culture conditions and application direction. Different cells have different lactonase activities, so the staining effect is different. 5. fluorescent dyes have quenching problems. Please avoid light during operation to slow down fluorescence quenching. 6. for your safety and health, please wear experimental clothes and disposable gloves.Usage method:1. Preparation of reagents(1) Preparation of CFDA SE storage solution: Take one tube of CFDA SE provided in the reagent kit and restore it to room temperature. Instantly centrifuge to allow the powder to fully settle to the bottom of the tube. Add 100 µ L CFDA SE solvent (add 20 µ L CFDA SE solvent) to it and dissolve it thoroughly to prepare CFDA SE storage solution (1000 ×). Prepared CFDA SE storage solution, stored at -20 ℃ in the dark, with a shelf life of two months- Storing at 70 ℃ in the dark can extend the usage time appropriately.(2) Preparation of CFDA SE Buffer: Dilute 10 x CFDA SE Buffer to 1 x with sterile cell culture grade water as needed. The prepared 1 × CFDA SE Buffer can be stored at 4 ℃ and can be stored at -20 ℃ if not in use for a long time.2. Marking and detection(1) Centrifuge the collected cells, use 1 mL 1 × CFDA SE Buffer to re suspend the cells in a 15 mL centrifuge tube, and adjust the cell concentration to 1-5 × 106 cells/mL.(2) Preparation of CFDA SE working solution: Dilute the CFDA SE storage solution (1000 ×) with 1 × CFDA SE Buffer to 2 ×.(3) Staining: Add 1 mL of CFDA SE working solution (2 x) to 1 mL of cell suspension to be labeled, invert and mix well, and incubate at 37 ℃ for 10 minutes.(4) Immediately add 5 times the volume of preheated complete culture medium (including serum) to the centrifuge tube, invert and mix well to terminate the labeling reaction.(5) Centrifuge at 1000 rpm for 5 minutes at room temperature to remove the supernatant, then wash once with 5-10 mL of complete culture medium.(6) Add 5-10 mL of complete culture medium and incubate at 37 ℃ for 5 minutes to promote the residence of CFDA SE in the cells and the entry of unreacted CFDA SE into the complete cell culture medium. Centrifuge at 1000 rpm for 5 minutes at room temperature to remove the supernatant and complete the final wash.(7) Subsequently, the cells can be cultured using the normal cultivation method. The labeling effect can be directly observed under a fluorescence microscope, or cell proliferation can be detected by flow cytometry after appropriate cultivation time, showing green fluorescence. The labeled cells can also be used for transplantation in live animals and for fluorescence tracing.Note: a If cell fixation is required, use aldehyde fixatives such as 4% paraformaldehyde to fix at room temperature for 15 minutes; If additional labeling such as antibody labeling is required afterwards, please permeabilize the cells with ice acetone for 10 minutes. b. The optimal labeling concentration and incubation time for CFDA SE vary for different cells. The initial experiment can be conducted according to the experimental steps. If the effect is not satisfactory, it is recommended to adjust the staining concentration and incubation time to achieve the best labeling effect.Scope of application:Cell proliferation assay... Read More | FFPE DNA/RNA KitFixed Tissue DNA/RNA Extraction Kit Catalog number: F666120 (50 preps)Storage conditions: DNase I and 10×Reaction Buffer -20℃, Spin Columns DF and Spin Columns RS can be stored at room temperature for 2 months, 2-8℃ for 1 year, the rest of the components are stored FFPE DNA/RNA KitFixed Tissue DNA/RNA Extraction Kit Catalog number: F666120 (50 preps)Storage conditions: DNase I and 10×Reaction Buffer -20℃, Spin Columns DF and Spin Columns RS can be stored at room temperature for 2 months, 2-8℃ for 1 year, the rest of the components are stored at room temperature (15-30℃).Products Content:Products IntroductionThis kit is suitable for the effective purification of genomic DNA and total RNA from paraffin-embedded tissues, using specially optimized deparaffinizing agents and lysates to release DNA and RNA from tissue section samples, without the use of the organic reagent xylene, and without the need for overnight operation; the digested samples are incubated at higher temperatures to remove inhibitors caused by cross-linking, which can effectively improve nucleic acid yields and purity; and an optimized buffer system allows nucleic acids in the lysate to bind specifically to the adsorbent membrane, and inhibitors are effectively removed by a two-step rinsing procedure. The optimized buffer system enables the nucleic acids in the lysate to bind specifically to the adsorbent membrane, and the inhibitors are effectively removed by a two-step rinsing step, and finally eluted with low-salt buffer or water to obtain high purity DNA and RNA, and at the same time, equipped with a high-efficiency microsorbent column, the volume of the elution can be as low as 20 µl. The purified DNA and RNA can be directly used for PCR, Real-time PCR, SNP genotyping, STR genotyping, and so on. The purified DNA and RNA can be directly used for PCR, Real-time PCR, SNP genotyping, STR genotyping, second-generation sequencing, pharmacogenomics research and blot analysis.Self-contained reagent: anhydrous ethanolPre-experiment Preparation and Important Notes 1. After obtaining the sample, fix the sample as soon as possible, the fixation time of 14-24 hours is appropriate, too long a period of time will easily lead toDNA and RNA breaks, affecting downstream experiments. If the formaldehyde fixation time is too long or the sample is stored for too long(>1 year) is prone to compromise DNA integrity and failure to amplify long fragments.2. Ensure that samples are thoroughly dehydrated prior to embedding; residual formalin will inhibit Proteinase K action.3. Add 1.25 ml of Proteinase K Storage Buffer to Proteinase K to dissolve it, and store at -20℃. Do not leave the prepared Proteinase K at room temperature for a long period of time to avoid affecting its activity.4. Anhydrous ethanol should be added to Buffer RW2, Buffer GW1 and Buffer GW2 according to the label instructions on the vials before first use.5. Check Buffer GTL, Buffer GL and Buffer DS for crystallization or precipitation prior to use; if crystallization or precipitation occurs, redissolve Buffer GTL, Buffer GL and Buffer DS in a 37°C water bath.6. Preheat the water bath or thermostatic mixer to 56°C before starting the experiment.7. Use an ambient temperature centrifuge or set the centrifuge temperature to 25°C. Temperatures below 15°C may result in clogging of the adsorption column.8. To prevent RNase contamination, the following should be observed:1) Use RNase-free plastics and tips to avoid cross-contamination.(2) Glassware should be dry baked at 180°C for 4 hours before use, plasticware can be soaked in 0.5 M NaOH for 10 minutes, rinsed thoroughly with water and autoclaved.3) RNase-free water should be used to prepare the solution.(4) Operators wear disposable masks and gloves, and change gloves diligently during the experiment.procedureParaffin-embedded samples1. Trim off excess paraffin from the tissue block to expose the tissue and cut into 5-10 µm slices.2. Place approximately 1 x 1 cm2 slices (1-5 slices in total) in a centrifuge tube (supplied), add 500 µl of Buffer DS and vortex for 10 s. Briefly centrifuge the sample to the bottom of the tube. Centrifuge briefly to collect the sample at the bottom of the tube, incubate at 56°C for 3 minutes, remove from the water bath and allow to cool to room temperature before proceeding.Note: If the surface of the sample is exposed to air, discard the initial 2-3 slices without using them.3. Centrifuge at 12,000 rpm for 2 minutes and carefully discard the supernatant thoroughly without aspirating the precipitate. The residual dewaxing solution can be carefully removed with a small tip (10 µl).4. Add 180 µl of Buffer GTL and 20 µl of Proteinase K to the above tube and mix well with vortexing.5. Incubate at 56°C for 15 minutes, then place on ice for 3 minutes. Centrifuge at 12,000 rpm for 15 minutes at room temperature.6. Transfer the supernatant to a new 1.5 ml centrifuge tube for RNA extraction, taking care not to aspirate undigested tissue. Use the precipitate for DNA extraction. RNA extraction7. Take the supernatant obtained in step 6 and incubate at 80°C for 15 minutes.8. Add 320 µl of Buffer GL, mix by vortexing and shaking, then add 720 µl of anhydrous ethanol and mix immediately by vortexing and shaking.9. Add all of the resulting solution to the Spin Columns RS in the collection tube; if the solution cannot be added all at once, it may be transferred in several passes. centrifuge the column at 12,000 rpm for 1 minute, pour off the waste solution from the collection tube, and place the column back into the collection tube. Note: If the columns are clogged, the sample size may be too large and consideration should be given to reducing the number of starting sections to 1-2.Optional step: If genomic DNA is to be removed, the following steps can be followeda. Add 350 µl of Buffer RW1 to the column, centrifuge at 12,000 rpm for 1 minute, discard the waste solution, and place the column back into the collection tube.b. Preparation of DNase I mixture: Take 52 µl of RNase-Free Water and add 8 µl of 10×Reaction to it.Buffer and 20 µl DNase I (1 U/µl), mix well, and prepare a final volume of 80 µl of reaction solution.c. Add 80 µl of DNase I Mix directly to the adsorption column and incubate at 20-30°C for 15 minutes.d. Add 350 µl of Buffer RW1 to the column, centrifuge at 12,000 rpm for 1 minute, discard the waste solution, and return the column to the collection tube.Add 500 µl of Buffer RW2 to the adsorbent column, centrifuge at 12,000 rpm for 1 min, pour off the waste liquid in the collection tube, and put the adsorbent column back into the collection tube.11. Repeat step 10. centrifuge at 12,000 rpm for 2 minutes and pour off the waste liquid in the collection tube. Place the column at room temperature for 5 minutes.minutes to dry thoroughly.12. Place the column in a new RNase-free centrifuge tube and add 20-50 µl to the center of the column.RNase-Free Water, left at room temperature for 5 minutes, centrifuged at 12,000 rpm for 1 minute, and collected RNA solution, the-80°C for storage.DNA extraction7. Take the precipitate obtained in step 6 and add 180 µl Buffer GTL and 20 µl Proteinase K to the precipitate. VortexResuspend the precipitate for 15 seconds.8. Incubate at 56°C for 1 hour until the sample is completely dissolved. 90°C for 1 hour.Add 200 µl Buffer GL, vortex and shake to mix and then add 200 µl anhydrous ethanol, vortex and shake to mix thoroughly. Centrifuge briefly so that the solution on the wall of the tube collects at the bottom of the tube. Add all of the solution from step 9 to the Spin Columns DF in the collection tube, or transfer the solution in several passes. centrifuge at 12,000 rpm for 1 minute, pour off the waste solution from the collection tube, and return the column to the 10. collection tube.Note: If the adsorption column is clogged, the sample size may be too large and consideration should be given to reducing the number of starting sections to 1-2.11. Add 500 µl of Buffer GW1 to the adsorbent column and centrifuge at 12,000 rpm for 1 minute. Pour off the waste liquid from the collection tube and put the column back into the collection tube.12. Add 500 µl of Buffer GW2 to the adsorbent column and centrifuge at 12,000 rpm for 1 minute. Pour off the waste liquid from the collection tube and place the column back into the collection tube.Note: Step 12 may be repeated if further purity is required.13. 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 5 minutes to dry thoroughly. Note: The purpose of this step is to remove residual ethanol from the adsorbent column; ethanol residue will affect the subsequent enzymatic reaction. 14. Place the column in a new 1.5 ml centrifuge tube, add 20-50 µl Buffer EB to the center of the column, leave at room temperature for 5 minutes, centrifuge at 12,000 rpm for 1 minute, collect the DNA solution, and store at -20℃... Read More | The miRNA extraction kit is specifically designed to isolate and purify miRNAs from various animal tissues, plant tissues, cells, serum, plasma and other samples. It can also extract small molecule RNAs such as siRNA and snRNA that are less than 200 nt, and can also be used for the extraction of The miRNA extraction kit is specifically designed to isolate and purify miRNAs from various animal tissues, plant tissues, cells, serum, plasma and other samples. It can also extract small molecule RNAs such as siRNA and snRNA that are less than 200 nt, and can also be used for the extraction of total RNA. This product combines phenol/guanidine lysis technology and silicon matrix membrane purification technology. The unique lysis solution can effectively inhibit RNases while removing most of DNA and proteins from cell or tissue samples through organic extraction. For some sensitive downstream experiments, if miRNA enrichment is required, this kit can be used to enrich miRNA separately. This product is suitable for a wide range of samples, with high purity of prepared RNA, and can be directly used for sensitive downstream applications, such as Northern Blot analysis, Real Time PCR, Microarray Analysis, etc. M665531Component50 TStorageM665531ATRIzon Reagent60 mL2-8℃. Protect from ligt.M665531BBuffer RWT (concentrate)15 mLRTM665531CBuffer RW2 (concentrate)11 mLRTM665531DRNase-Free Water10 mLRTM665531ESpin Columns RM with Collection Tubes50 setsRTM665531FSpin Columns RS with Collection Tubes50 setsRTM665531GRNase-Free Centrifuge Tubes (1.5 mL)50 EART Self prepared reagents: chloroform, anhydrous ethanol (newly opened or dedicated for RNA extraction).Preparation and important precautions before the experiment:To prevent RNase pollution, attention should be paid to the following aspects:1) Use RNase free plastic products and gun heads to avoid cross contamination.2) Glassware should be dry baked at a high temperature of 180 ℃ for 4 hours before use, while plastic containers can be soaked in 0.5 M NaOH for 10 minutes, thoroughly rinsed with water, and then sterilized under high pressure.3) Prepare the solution using water without RNase.4) Operators should wear disposable masks and gloves, and change gloves frequently during the experiment.2. The extracted samples should avoid repeated freeze-thaw cycles, otherwise it will affect the quantity and quality of miRNA extraction.Before the first use, anhydrous ethanol should be added to Buffer RWT and Buffer RW2 according to the instructions on the reagent bottle label.4. All centrifugation steps should be carried out at room temperature unless otherwise specified, and all operation steps should be carried out quickly.Operation steps:Protocol A: miRNA enrichment (can be directly used for sensitive downstream experiments)1. Sample processing1a Organization: Grind the organization in liquid nitrogen. Add 1 ml of TRIzon Reagent to every 30-50 mg of tissue, shake and mix well. The sample volume shall not exceed one tenth of the volume of TRIzon Reagent.1b Single layer culture of cells: Remove the culture medium, add TRIzon Reagent, and add 1 ml of TRIzon Reagent every 10 cm2 (the amount of lysis solution depends on the area of the culture bottle).1c Cell suspension: Centrifuge to obtain cell precipitate, discard supernatant. Add 1 ml of TRIzon Reagent to every 5 x 106-1 x 107 cells (cells do not require washing).1d Plasma or serum: Take 200 µ Add 5 times the volume of TRIzon Reagent to plasma or serum samples, shake and mix well for 30 seconds.2. After adding TRIzon Reagent to the sample, blow it repeatedly several times to fully crack it. Leave at room temperature for 5 minutes to completely separate the protein nucleic acid complex.3. Optional steps: Centrifuge at 4 ℃ 12000 rpm (~13400 × g) for 5 minutes, take the supernatant, and transfer it to a new centrifuge tube (provided by oneself) (if the sample contains more proteins, fats, polysaccharides, etc., this step can be performed).4. Add chloroform to the supernatant and add 200 to every 1 ml of TRIzon Reagent used µ Chloroform, cover the tube, vigorously shake for 15 seconds, and let it sit at room temperature for 5 minutes.Centrifuge at 5.4 ℃ and 12000 rpm for 15 minutes. The sample is divided into three layers: red organic phase, middle layer, and colorless aqueous phase. Transfer the upper colorless aqueous phase to a new centrifuge tube (self prepared).6. Add 1/3 volume of anhydrous ethanol to the solution obtained in step 5, mix well, and transfer the obtained solution and precipitate together into the adsorption column RM (Spin Columns RM) that has been loaded into the collection tube. If you cannot add all the solution to the adsorption column at once, please transfer it multiple times. Centrifuge at 12000 rpm for 30 seconds, discard the adsorption column RM after centrifugation, and retain the effluent.7. Add 2/3 times the volume of anhydrous ethanol to the solution obtained in step 6 and mix well.8. Transfer the solution and precipitate obtained from the previous step into the adsorption column RS (Spin Columns RS) that has been loaded into the collection tube. If you cannot add all the solution to the adsorption column at once, please transfer it multiple times. Centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RS back into the collection tube.9. Add 700 to the adsorption column RS µ L Buffer RWT (check if anhydrous ethanol is added before use), centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RS back into the collection tube.10. Add 500 to the adsorption column RS µ Buffer RW2 (check if anhydrous ethanol is added before use), centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RS back into the collection tube.11. Repeat step 10.12. Centrifuge at 12000 rpm for 1 minute and discard the waste liquid from the collection tube. Place the adsorption column RS 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 RS, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).13. Place the adsorption column RS in a new RNase free centrifuge tube and add 30-50 to the middle of the adsorption column µ Place RNase Free Water at room temperature for 1 minute, centrifuge at 12000 rpm for 1 minute, collect RNA solution, and store the obtained RNA solution at -70 ℃ to prevent degradation.Attention:1) The volume of RNase Free Water should not be less than 30 µ l. Small volume affects the recovery rate.2) If you want to increase RNA production, you can use 30-50 µ Repeat step 13 for the new RNase Free Water.3) If you want to increase the RNA concentration, you can add the obtained solution back to the adsorption column RS and repeat step 13Protocol B: Extraction of total RNA (including miRNA and other small molecule RNAs<200 nt), steps 1-5 are the same as protocol A.6. Add 1.25 times the volume of anhydrous ethanol to the solution obtained in step 5 and mix well.7. Transfer the solution and precipitate obtained from the previous step into the spin columns RM that have been loaded into the collection tube. If you cannot add all the solution to the adsorption column RM at once, please transfer it multiple times. Centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RM back into the collection tube.8. Add 700 to the adsorption column RM µ L Buffer RWT (check if anhydrous ethanol is added before use), centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RM back into the collection tube.9. Add 500 to the adsorption column RM µ Buffer RW2 (check if anhydrous ethanol is added before use), centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RM back into the collection tube.10. Repeat step 9.11. Centrifuge at 12000 rpm for 1 minute and discard the waste liquid from the collection tube. Place the adsorption column RM at room temperature for a few minutes to thoroughly air dry. Attention: The purpose of this step is to remove residual ethanol from the adsorption column RM, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).12. Transfer the adsorption column RM into a new RNase free centrifuge tube and add 30-50 to the middle of the adsorption column µ Place RNase Free Water at room temperature for 1 minute, centrifuge at 12000 rpm for 1 minute, collect RNA solution, and store the obtained RNA solution at -70 ℃ to prevent degradation. Attention: 1) The volume of RNase Free Water should not be less than 30 µ l. Small volume affects the recovery rate.2) If you want to increase RNA production, you can use 30-50 µ Repeat step 12 for the new RNase Free Water.3) If you want to increase the RNA concentration, you can add the obtained solution back to the adsorption column RM and repeat step 12... 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 |