| Description | Inquire | The bacterial viability / toxicity detection kit contains two fluorescent dyes. Nucgreen is a green nucleic acid dye that can stain live and dead bacteria; Ethd III is a red nucleic acid dye that only stains dead bacteria with damaged cell membranes. When nucgreen and ethd III are properly mixed, The bacterial viability / toxicity detection kit contains two fluorescent dyes. Nucgreen is a green nucleic acid dye that can stain live and dead bacteria; Ethd III is a red nucleic acid dye that only stains dead bacteria with damaged cell membranes. When nucgreen and ethd III are properly mixed, the bacteria with intact cell membrane appear green, while the bacteria with damaged cell membrane can appear green and red under different channels, respectively. A common criterion for bacterial viability is the ability to propagate in a suitable nutrient medium, known as a growth assay. This kit is generally in good agreement with the growth assay results in liquid or solid medium. However, under certain conditions, membrane damaged bacteria may recover and propagate in nutrient medium, and such bacteria will be identified as dead bacteria in this assay. On the contrary, some bacteria with intact membranes may not be able to propagate in nutrient medium, but will be recognized as viable bacteria in this assay. Therefore, if there is a large difference between the test results of this kit and the bacterial growth assay, the above possibilities should be considered. Component： Product parameters： NucGreen: Ex/Em = 503/530 nm (结合 DNA)；EthD-III: Ex/Em = 530/620 nm (结合 DNA)。Usage:1 Preparation of control samples for live and dead bacteria (optional)1. Cultivate 4 mL of bacteria in liquid medium until late logarithmic phase.2. Prepare two 1 mL bacterial solutions in an EP tube and centrifuge for 10-15 minutes under 5000-10000 g conditions.3. Remove the supernatant and add 0.3 mL of 0.85% NaCl resuspended bacteria to one of the EP tubes, and 1 mL of 0.85% NaCl resuspended bacteria to the other tube.4. Add 0.7 mL of isopropanol to a tube containing 0.3 mL of 0.85% NaCl, and mix thoroughly (with a final concentration of 70% isopropanol) to prepare a dead bacterial sample.5. Incubate the two samples at room temperature for 1 hour and mix every 15 minutes.6. Centrifuge the two samples at 5000-10000 g for 10-15 minutes.7. Remove the supernatant, add 1 mL of 0.85% NaCl to resuspend the bacteria in both samples, and centrifuge again as in step 6.8. Use a spectrophotometer to measure the absorbance values (OD670) of two bacterial suspensions at 670 nm.9. Adjust the density of the two bacterial suspensions (live and dead) to 108 bacteria/mL (OD670 ≈ 0.3), and then dilute with 0.85% NaCl at 1:100 to achieve a final density of 106 bacteria/mL.10. Mix two bacterial suspensions as shown in the table below to obtain the required live cell ratio: dead cell ratio.Table 1 Mix live and dead bacterial suspensions by a certain volume to achieve the required ratio of live and dead cellsLive cells: Dead cellsVolume of viable bacterial suspension（mL）Volume of dead bacterial suspension（mL）0:10001.010:900.10.920:800.20.830:700.30.750:500.50.5100:01.00II Staining methods for fluorescence microscopy observation1. Mix 1 volume of component A, NucGreen, and 2 volumes of component B, EthD-III, in a microcentrifuge tube. After thorough mixing, add 8 volumes of 0.85% NaCl solution to obtain a 100 x dye solution.2. Every 100 µ L bacterial suspension, add 1 µ 100 x dye solution of L.3. Mix thoroughly and incubate at room temperature in the dark for 15 minutes.4. Take 5 µ The bacterial suspension after L staining was dropped onto a glass slide with an 18 mm square cover glass.5. Observe under a fluorescence microscope. The fluorescence of live and dead bacteria can be observed simultaneously under any standard FITC long-acting filter. Alternatively, live (green fluorescent) and dead (red fluorescent) bacteria can be observed using FITC and Cy3 (or Texas Red) channels, respectively.Attention: (1) Before staining bacteria, attention must be paid to removing residues of growth media. Nucleic acid and other media components can bind to NucGreen and EthD-III dyes in some way, resulting in unacceptable staining changes. A simple washing step is usually sufficient to remove interfering media components from bacterial suspension. It is not recommended to use phosphate buffer solutions as they can reduce staining efficiency. (2) Before starting the formal experiment, the dye concentration should be adjusted to distinguish between NucGreen labeling live bacteria and EthD-III labeling dead bacteria. The optimal concentration may vary depending on the bacterial strain. It is generally best to use the lowest dye concentration that can provide sufficient signal. The above conditions have been optimized for staining live/dead cells of Escherichia coli.III Before starting the staining method experiment of flow cytometry, please read the precautions under the fluorescence microscope staining steps.According to Table 1, add 11 different proportions of live and dead bacteria to the EP tube. Each of the 11 samples has a volume of 1 mL.2. Add 12 µ The A component of L, NucGreen, and 24 µ The B component EthD-III of L was mixed in a microcentrifuge tube. Add 3 to each of the 11 samples µ Mix the mixed dyes of L thoroughly by blowing them up and down several times. (Note: Additional control bacterial samples need to be prepared for separate NucGreen and EthD-III staining)3. Incubate at room temperature in the dark for 15 minutes.4. Analyze each sample using a flow cytometer, detect NucGreen positive cells using FITC channels, and detect EthD-III positive cells using PI or PE channels.Matters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. if the orifice plate is used for detection, a small amount of bacterial liquid can be left for imaging after standing for 10 min, which can effectively reduce the background. 3. in order to be closer to the real results, it is recommended to keep the brightness of red fluorescence consistent with that of green fluorescence in merge pictures. 4. fluorescent dyes have quenching problems. Please try to avoid light during experimental operation to slow down fluorescence quenching. 5. for your safety and health, please wear experimental clothes and disposable gloves.Scope of application：Staining of dead and live bacteria... Read More | Inquire | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export | Product contentcomponent50T200TBuffer LP125mL100mLBuffer LP210mL40mLBuffer LP3 (concentrate)21ml84mlBuffer GW2 (concentrate)15mL75mlBuffer GE15mL60mLRNase A（10 mg/ml）300µl1.25mLSpin Columns DM with Collection Tubes50200ProductsThis kit uses centrifugal adsorption columns with highProduct contentcomponent50T200TBuffer LP125mL100mLBuffer LP210mL40mLBuffer LP3 (concentrate)21ml84mlBuffer GW2 (concentrate)15mL75mlBuffer GE15mL60mLRNase A（10 mg/ml）300µl1.25mLSpin Columns DM with Collection Tubes50200ProductsThis kit uses centrifugal adsorption columns with high efficiency and specific binding of nucleic acids and a unique buffer system, which is suitable for extracting genomic DNA from a wide variety of different fresh or frozen plant tissues with maximum removal of impurities from the plant tissues. The kit eliminates the need for phenol/chloroform extraction and is safe to handle. The extracted genomic DNA fragments are large, high purity, stable and reliable quality, suitable for PCR, fluorescence quantitative PCR, molecular labeling, library construction and other 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 LP3 and Buffer GW2 according to the instructions on the label of the reagent bottle before first use. Check Buffer LP1 and Buffer LP2 for crystallization or precipitation before use. If crystallization or precipitation occurs, re-dissolve Buffer LP1 and Buffer LP2 in a 56°C water bath. Procedure1. Take about 100mg of fresh plant tissue or about 20mg of dry weight tissue and add liquid nitrogen to grind it fully.2. Collect the ground powder into a centrifuge tube (self-provided), add 400 µl Buffer LP1 and 6 µl RNase A (10 mg/ml), vortex and oscillate for 1 minute, and leave it at room temperature for 10 minutes to allow for full cleavage.Note: 1) Use vortex shaking or pipette blowing to fully lyses the tissue, incomplete tissue lysis will affect the final DNA yield. 2) Do not mix Buffer LP1 with RNase A prior to use.3. Add 130 µl Buffer LP2, mix well and vortex for 1 minute.4. Centrifuge at 12,000 rpm (~13,400 x g) for 5 minutes and transfer the supernatant to a new centrifuge tube (supplied).5. Add 1.5 times the volume of Buffer LP3 (check that anhydrous ethanol has been added before use) and mix thoroughly (e.g., 500 µl filtrate to 750 µl Buffer LP3).Note: Buffer LP3 should be mixed immediately after addition; precipitation may occur but will not affect subsequent experiments.6. Add all of the solution and precipitate obtained in the previous step to the adsorption columns (Spin Columns DM) that have been loaded into the collection tubes, if the solution cannot be added all at once, it can be transferred in several times. centrifuge the columns at 12,000 rpm for 1 minute, pour off the waste liquid in the collection tubes, and put the columns back into the collection tubes.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: If the adsorbent membrane appears green, add 500 µl of anhydrous ethanol to the adsorbent column, centrifuge the column at 12,000 rpm for 1 minute, pour off the waste liquid in the collection tube, and put the adsorbent column back into the collection tube.8. Repeat step 7.9. 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.).10. Place the adsorption column in a new centrifuge tube (supplied), add 50-100 µl of Buffer GE or sterilized water dropwise to the middle of the adsorbent membrane, leave it at room temperature for 2-5 minutes, and centrifuge it at 12,000 rpm for 1 minute to collect the DNA solution. -The DNA solution was collected by centrifugation at 12,000 rpm for 1 min.Note: 1) If the downstream experiment is sensitive to pH or EDTA, you can use sterilized water for elution. The pH value of the eluent has a great influence on the elution efficiency, if you use water as the eluent, you should ensure that the pH value is 7.0-8.5 (you can use NaOH to adjust the pH value of the water to this range), and when the pH value is lower than 7.0, the elution efficiency is not high.2) Incubation at room temperature for 5 minutes prior to centrifugation increases yield.(3) If the final concentration of DNA is to be increased, the DNA eluate obtained in step 10 can be re-added to the adsorbent membrane and repeat step 10; if the elution volume is less than 100µl, the final concentration of DNA can be increased, but it may reduce the total DNA yield. If the amount of DNA obtained is less than 1µg, 50µl Buffer GE is recommended for elution.4) Because DNA stored in water is subject to acidic hydrolysis, for long-term storage, elution with Buffer GE and storage at -20°C are recommended... Read More |