| 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 | Product contentG665801Component100 TStorageG665801A2×GoldStar Probe One Step Buffer1.4 mL-20℃. Avoid freeze/ Thaw cycle. Protect from light.G665801BGoldStar Probe One Step EnzymeMix100 µL-20℃. Avoid freeze/ Thaw cycle. Protect from light.G665801C50×High ROX50 µL-20&#Product contentG665801Component100 TStorageG665801A2×GoldStar Probe One Step Buffer1.4 mL-20℃. Avoid freeze/ Thaw cycle. Protect from light.G665801BGoldStar Probe One Step EnzymeMix100 µL-20℃. Avoid freeze/ Thaw cycle. Protect from light.G665801C50×High ROX50 µL-20℃. Avoid freeze/ Thaw cycle. Protect from light.G665801DRNase-Free Water1.5 mL-20℃. Avoid freeze/ Thaw cycle. Product Introduction This product is a specialized kit for one-step Real-Time RT-qPCR using the probe method (TaqMan, Molecular Beacon, etc.). When using this product for Real Time RT-qPCR reaction, reverse transcription and quantitative PCR are carried out in the same reaction system, and there is no need to add reagents or open the cap of the tube during the reaction process, which avoids contamination and improves the experimental efficiency at the same time. With high detection sensitivity, strong fluorescence signal and high signal-to-noise ratio, this product is very suitable for the detection of RNA viruses and other trace RNA. The special buffer system contained in this product can maximize the effectiveness of reverse transcriptase and DNA polymerase at the same time and improve the efficiency of the reaction. A wider linear range can be obtained with this product, more accurate quantification of the target gene, good reproducibility and high confidence.ROX dye is used to correct the fluorescence signal error generated between wells of a quantitative PCR instrument, and is generally used in Real Time PCR amplifiers from ABI, Stratagene, and other companies. The excitation optics vary from instrument to instrument, so the concentration of ROX dye must be matched to the corresponding fluorescence quantitative PCR instrument. Instruments that do not require ROX calibration (G665836) Roche LightCycler 480, Roche LightCyler 96, Bio-rad iCyler iQ, iQ5, CFX96 and others. Instruments that require High ROX calibration (G665801) ABI Prism 7000/7300/7700/7900, Eppendorf, ABI Step One/Step One Plus, and others.matters needing attention1.Before using the reagents in this kit, please mix them gently by turning them up and down to avoid foaming as much as possible, and use them after brief centrifugation.2.This product uses RNA as the template for one-step RT-PCR experiment, RNase contamination should be avoided during operation, it is recommended to operate RNA in a special area, use special instruments and consumables, the operator with a mask and disposable gloves and often change the gloves, the experiment-related consumables should be processed with 0.1% DEPC (diethyl ether pyrocarbonate) aqueous solution for 12 hours at 37℃, and autoclaved for 30 minutes before use. The consumables should be treated with 0.1% DEPC (diethylpyrocarbonate) aqueous solution at 37℃ for 12 hours and autoclaved for 30 minutes.3.Repeated freezing and thawing of each reagent in this kit should be avoided as much as possible; repeated freezing and thawing may degrade the product performance.4.This kit must use specific primers, the choice of primers can be selected according to specific experiments, the good or bad primer design directly affects the results of RT-qPCR reaction, the design of primers need to consider the GC content, primer length, primer position, the secondary structure of the PCR product and other factors, it is recommended to use a professional primer design software for design.5.This kit is recommended to use specific probes, and it is recommended to use professional design software for designing.UsageThe following examples are conventional reaction systems and conditions, which should be improved and optimized according to the different templates, primer structures and target fragment sizes in actual operation. (Please prepare the reaction solution on ice.)1. Dissolve RNA template, primers, 2× GoldStar Probe One Step Buffer, GoldStar Probe One Step EnzymeMix and RNase-Free Water and set aside on ice.2. PCR reaction system:reagents25µl reaction systemfinal concentration2×GoldStar Probe One Step Buffer12.5µl1×Forward Primer, 10µM0.5µl0.2µM¹⁾Reverse Primer, 10µM0.5µl0.2µM¹⁾Probe, 10µM0.5µl0.2µM²⁾GoldStar Probe One Step EnzymeMix1.0µl RNA TemplateXµl10pg-100ng³⁾50 x Low ROX or High ROX (optional)⁴⁾0.5µl1×RNase-Free WaterUp to 25µlNote: 1) Usually, better results can be obtained with a primer concentration of 0.2 µM, and 0.1-1.0 µM can be used as a reference for setting the range.(2) The concentration of the probe used is related to the fluorescence quantitative PCR instrument used, the type of probe, and the type of fluorescent labeling substance, please refer to the instrument manual or the specific requirements for the use of each fluorescent probe for the adjustment of the concentration in actual use.(3) Usually the amount of RNA template is 10pg-100ng as a reference. Since the templates of different species contain different copy numbers of target genes, the templates can be diluted in gradient to determine the optimal amount of template to use.(4) The excitation optical system varies from instrument to instrument, choose to add 50×Low ROX or 50×High ROX according to the instrument using fluorescence quantification.3. Mix well, centrifuge briefly, and collect the solution at the bottom of the tube.4.RT-PCR reaction conditions:Note: 1) The hot start enzyme used in this product must be activated under the condition of pre-denaturation 95℃, 5-10min. 2) It is recommended to use the two-step PCR reaction program, if you can not get good experimental results due to the use of primers with lower Tm value, etc., you can try to carry out the three-step PCR amplification, and the annealing temperature should be set in the range of 56℃-64℃ as a reference... Read More | Products contentNote: The amount of individual primers used is 1 µl, each N7-end primer can perform 10 DNA library constructs, and each kit can perform 240 DNA library constructs.Products IntroductionThis kit is a companion kit to the transposase-based Rapid DNA Library Construction Kit for Products contentNote: The amount of individual primers used is 1 µl, each N7-end primer can perform 10 DNA library constructs, and each kit can perform 240 DNA library constructs.Products IntroductionThis kit is a companion kit to the transposase-based Rapid DNA Library Construction Kit for Illumina platform library construction. Each kit contains one N5 primer and 24 N7 primers, which can be used to prepare 24 different single-ended Index libraries. All reagents provided in the kits have been subjected to stringent quality control and functional validation to maximize the stability and reproducibility of library construction. The libraries can be used for sequencing on Illumina platforms such as HiSeq X-10/4000/2500/2000 and MiSeq. Provide your own instruments, reagents and consumables1. Magnetic frame: DynaMagTM-2 is recommended.2. DNA purification and recovery kit: It is recommended to use Kangwei DNA purification and recovery kit by magnetic bead method.3. DNA building kit: It is recommended to use the Kangwei Century transposase method second-generation sequencing rapid DNA building kit.4. Anhydrous ethanol.5. Reaction tubes: It is recommended to use low adsorption PCR tubes with 1.5 ml centrifuge tubes; Tip: It is recommended to use a high quality filter tip to prevent contamination of kits and library samples. Pre-experiment Preparation and Important NotesPlease centrifuge briefly before opening the cap so that the liquid collects at the bottom of the tube to avoid cross-contamination between different primers. procedureFor the use of the CombiVision Second Generation Sequencing Multisample Primer Kit, please follow the CombiVision Second Generation Sequencing Rapid DNA Library Kit protocol. Index N501 Primer for Illumina Index N901-N996 Primer for Illumina... Read More | Inquire |