| Description | Inquire | Calcein AM /PI Double Staining Kitis utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stains viable and dead cells, respectively(Fig. 1). Calcein-AM, an acetoxymethyl ester of calcein, is highly Calcein AM /PI Double Staining Kitis utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stains viable and dead cells, respectively(Fig. 1). Calcein-AM, an acetoxymethyl ester of calcein, is highly lipophilic and cell membrane permeable. Though Calcein-AM itself is not a fluorescent molecule, the calcein generated from Calcein-AM by esterase in a viable cell emits a strong green fluorescence (excitationat 490 nm, emission at515 nm). Therefore, Calcein-AM only stains viable cells. On the other hand, PI, a nuclei staining dye, cannot pass through a viable cell membrane. It reaches the nucleus by passing through disordered areas of dead cell membrane, and intercalates with the DNA double helix of the cell to emit red fluorescence (excitation: 535 nm,emmision: 617 nm). Since both calcein and PI-DNA can be excited with 490 nm, simultaneous monitoring of viable and dead cells is possible with a fluorescence microscope. With 545 nm excitation, only dead cells can be observed (Fig. 1). Since optimal staining conditions differ from cell line to cell line, we recommend that a suitable concentration of PI and Calcein-AM be individually determined. Please note that PI is suspected to be highly carcinogenic;careful handling is required.Required Equipment and Materials:Microscope with 490 nm excitation filter and 530 nm emission filter；CO2incubator；10 µl and 200 µl adjustable pipettes, PBSSolution A (Calcein-AM)；Solution B (PI) Storage Condition: -20oC ；Shipping Condition: blue ice.Application:Assay Procedure1)Add 2.5 µl Solution A and 12.5 µl Solution B to 5 ml PBS to prepare assay solution.*2)Wash the cell with PBS several times to remove residual esterase activity.3)Add 100uLof assay solution to200uL105~106CELLSsolution and incubate the mixture at 37oC for 15 min.4)Detect fluorescence using a fluorescence mircoscope with 490 nm excitationfor simultaneous monitoring of viable and dead cells.With 545 nm excitation, only dead cells can be observed.*The following steps may be necessary tooptimizethe suitable concentration of each reagent:1)Prepare dead cells by 10 min incubation in 0.1% saponin or 0.1-0.5% digitonin or by 30 min incubation in 70% ethanol.2)Stain dead cells with 0.1-10 µM PI solution to find a PI concentration that stains the nucleus only, not the cytosol.3)Stain dead cells with 0.1-10 µM Calcein-AM solution to find a Calcein-AM concentration that does not stain the cytosol. Then stainviable cells with that Calcein-AM solution to check whether the viable cell can be stained... Read More | Apoptosis refers to the cell autonomous and orderly death controlled by genes to maintain the stability of the internal environment. Apoptosis is different from cell necrosis. Apoptosis generally refers to a programmed cell death process that occurs during the development of body cells or under the Apoptosis refers to the cell autonomous and orderly death controlled by genes to maintain the stability of the internal environment. Apoptosis is different from cell necrosis. Apoptosis generally refers to a programmed cell death process that occurs during the development of body cells or under the action of some factors through the regulation of intracellular genes and their products. Cell necrosis is a cell death process that is caused by strong physical and chemical or biological factors to cause disordered changes in cells. The difference between apoptosis and necrosis lies in the characteristic morphological and biochemical changes, including the changes of cell membrane permeability and nuclear chromatin, the contraction of cytoplasm and the loss of membrane asymmetry. The oxazole yellow/pi membrane permeability apoptosis detection kit produced by our company is a dual fluorescence detection kit based on oxazole yellow and PI dyes. This kit is suitable for fluorescence microscopy, flow cytometry, fluorescence microplate reader and other fluorescence detection systems. Oxazole yellow is a non cell membrane penetrating cyanine monomer green fluorescent dye with high affinity for DNA. It basically has no fluorescence when it is not bound to DNA, but can emit bright green fluorescence after binding to DNA. When apoptosis occurs, the permeability of cell membrane changes. At this time, oxazole yellow can enter the cell and bind to DNA, emitting bright green fluorescence. Therefore, it is often used for the detection of apoptosis. It should be noted that oxazole yellow can also stain dead cells, so it needs to be double stained with PI that specifically fluorescently stains dead cells to effectively determine apoptosis. PI (propidium iodide) is a red fluorescent dye that can stain DNA. It is an analog of pyridine bromide that releases red fluorescence after embedding double stranded DNA. Although PI cannot pass through the membrane of living cells, it can cross the damaged cell membrane of dead cells to stain nuclei. Therefore, oxazole yellow combined with PI can be directly used for the detection of apoptosis. Apoptotic cells show green fluorescence, dead cells show both red and green fluorescence positive, and living cells have little or no fluorescence.Components: Components O598364-50T A. Oxazole yellow dye 50 µL B. Propidium Iodide (PI) 50 µLUsage (using flow cytometry as an example):1. Cell preparation(1) For adherent cells, after trypsin digestion, resuspend in culture medium and wash once with pre cooled PBS; The digestion time of trypsin should not be too long to prevent false positives. Note: Digest with trypsin and allow the cells to recover in the optimal cell culture conditions and medium for about 30 minutes, then stain.(2) For suspended cells, centrifuge at 1000 rpm for 5 minutes, discard the supernatant, and wash once with pre cooled PBS.2. Cell stainingSuspend cells in pre cooled PBS, with a recommended cell count of 106 cells/mL per sample. Add 1 µ L Oxazole Yellow and 1 µ L to 1 mL of the samplePI， Gently blow and mix well. Incubate on ice in the dark for 30 minutes. Note: We suggest adding the following two experimental controls:Blank tube: negative control group cells, without dye, used to regulate voltage.Single staining tube: Positive control group cells were treated with only two tubes, Oxazole yellow and PI, for regulating compensation.3. Flow detectionAfter incubation, the sample can be directly detected by flow cytometry, or centrifuged at 1000 rpm for 5 minutes, the supernatant can be aspirated, and the sample can be resuspended in 1 mL of pre cooled PBS for flow cytometry detection. Oxazole yellow can be excited by a 488 nm laser, and the detected fluorescence emission spectrum is around 530 ± 30 nm (FITC channel), while the PI channel emission spectrum is around 617 nm (PI or PE channel).Product parameters：Oxazole yellow dye:ex/em = 491 / 509 nm (bound DNA); Propidium iodine:ex/em = 535 / 617 nm (combined with DMatters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. fluorescent dyes have quenching problems. Please try to avoid light to slow down fluorescence quenching. 3. for your safety and health, please wear experimental clothes and disposable gloves.Scope of application：Membrane permeability apoptosis assay... 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 | Component Description T665563Component50 TStorageApplicationT665563AVNTR3820 1 mL-20℃. Avoid freeze/thaw cycle.High resolution 3-lite VNTR detectionT665563BVNTR41201 mL-20℃. Avoid freeze/thaw cycle.High resolution 3-lite VNTR detectionT665563CVNTR32321 mL-20℃. Avoid freeze/thaw Component Description T665563Component50 TStorageApplicationT665563AVNTR3820 1 mL-20℃. Avoid freeze/thaw cycle.High resolution 3-lite VNTR detectionT665563BVNTR41201 mL-20℃. Avoid freeze/thaw cycle.High resolution 3-lite VNTR detectionT665563CVNTR32321 mL-20℃. Avoid freeze/thaw cycle.High resolution 3-lite VNTR detectionT665563DMarkerⅠ300 µL-20℃. Avoid freeze/thaw cycle.DNA Molecular Weight Standard IT665563EMarkerⅡ250 µL-20℃. Avoid freeze/thaw cycle.DNA Molecular Weight Standard IIProduct IntroductionThis kit is a genotyping product for human Mycobacterium tuberculosis based on the latest research progress in molecular epidemiology1) and optimized by process. It utilizes variable-number tandem repeats (VNTR) polymorphisms in the Mycobacterium tuberculosis genome for genotyping to differentiate clinical strains, and is a powerful tool for studying the molecular epidemiology of Mycobacterium tuberculosis and monitoring the status of tuberculosis transmission. Compared with other existing Mycobacterium tuberculosis VNTR typing systems based on the VNTR principle, this typing system has a stronger ability to discriminate strains prevalent in China1,2,3), and is therefore particularly suitable for the needs of Chinese users.By carefully optimizing the primer sequences of each PCR reaction and the composition of the premixed reaction solution, this product has a strong anti-interference power. Compared with the user's own reagents, this product significantly improves the signal intensity of specific bands and reduces the appearance of non-specific bands when using crude templates (boiling bacterial solution), which makes the experimental operation easier and quicker, and at the same time, improves the success rate of the test. The premixed reaction solution is chemically stable and can effectively withstand repeated freezing and thawing (10 times) and a longer period of time (one week) at room temperature, which is better adapted to the user's need for flexibility in the detection work.This kit is a companion product to the TB Genotyping Kit VNTR-9. For samples identified as clustered or identical strains by the VNTR-9 kit, this product can be used for finer further typing identification if necessary. The three high-resolution detection sites VNTR3820, VNTR4120 and VNTR3232 in this product can be used in combination with the nine detection sites in the VNTR-9 to increase the resolution index (Hunter-Gaston index (HGI) to 0.9931).References1) Luo T et al. Development of a hierarchical variable-number tandem repeat typing scheme for Mycobacterium tuberculosis in China. PLoS One. 2014 Feb 25. 9(2)2)Sun G et al. Discriminatory potential of a novel set of Variable Number of Tandem Repeats for genotyping Mycobacterium marinum. Vet Microbiol. 2011 Aug Vet Microbiol. 2011 Aug 26;152(1-2)3) Zhang L et al. Highly polymorphic variable-number tandem repeats loci for differentiating Beijing genotype strains of Mycobacterium tuberculosis in Shanghai, China. FEMS Microbiol Lett. 2008 May;282(1):22-31.matters needing attention1.This product is a companion to the TB genotyping kit VNTR-9. The strains to be tested should be tested by VNTR-9 typing test first, and then use this product for testing. And the results of this product should be integrated and analyzed with the results of VNTR-9.2.To avoid contamination, it is recommended that the preparation of the organisms be done within a different location than the preparation of the PCR Mix and that different pipettes be used.3.Care should be taken at all stages of sample DNA collection, extraction and amplification to ensure proper labeling and to prevent cross-contamination between different samples.4.Commonly used reagents and consumables need to be autoclaved before experimentation.5.Each tube of PCR Mix contains different primers and cannot be mixed. It can be dispensed into different amounts at once according to the experimental needs to avoid repeated freezing and thawing.6.To avoid splashing the reaction solution when opening the reaction tube, centrifuge briefly before opening the cap and collect the liquid at the bottom of the tube. In case of accidental splashing on gloves or table, change gloves immediately and wipe the table with 75% alcohol or dilute acid.7.Be careful not to cross-contaminate the PCR Mix when aspirating, and it is recommended that the pipette tip be wiped with 75% alcohol 2 times before taking Mix each time.8.Pre-experiment preparation: 1×TE buffer (PH=8.0), 0.5×TBE buffer, agarose, ethidium bromide (EB), normal PCR instrument, DNA electrophoresis equipment and gel imager, 0.2 ml PCR reaction tubes, octuplex or 96-well PCR tubes, pipettes of different sizes: 0.5-10 µl and 20-200 µl.Operation steps1. DNA template preparation:1.1. scrape a small amount (1-2 inoculation loops) of sample from solid medium, resuspend in 100ul TE and inactivate at 80°C for 30 minutes.1.2. The inactivated strain was taken out of the P3 laboratory as follows:Boil at 100°C for 10 minutes (be careful to avoid bursting the cap of the EP tube during boiling to avoid letting water into the tube), place immediately on ice for 2 minutes, centrifuge at 12,000 rpm (~13,400 × g) for 10 minutes, take the supernatant and place in another sterile EP tube, label it, and store at -20°C.2. Testing procedures:2.1. Remove the TB Genotyping Kit HV-3, allow the liquid to equilibrate to room temperature, mix by shaking slightly 3-4 times, and then centrifuge at 12,000 rpm (~13,400 x g) for 5 seconds to allow the capped liquid to fall back into the tube.2.2.Three-locus VNTR typing: strains with identical results at 12 loci need to be further VNTR typed, i.e., the following four loci are added for comparison.1）PCR amplification: the reaction system was 20 µl. 19 µl of PCR Mix of VNTR3820, VNTR4120, and VNTR3232 were added to each PCR tube, 1 µl of DNA template was added, and mixed well.2）Amplification conditions:3) Gel preparation and electrophoresis:a: Notes:Important! Positive (H37Rv strain DNA) and negative controls (deionized water) need to be set up for each experiment.Key! This experiment is based on agarose gel electrophoresis to interpret the genotype of VNTR locus, therefore, in order to make the results accurate, it is necessary to follow the unified standard operation in this step of electrophoresis, and the following points should be noted:a-1: The comb used for glue making is 18 holes.a-2: The two wells on the left and right sides of the gel were discarded due to the tendency to distort the bands during electrophoresis, affecting the interpretation of the results, or a negative control was spotted in one of the wells. The remaining 16 wells were divided into 12 samples, 3 DNA Markers and 1 positive control. The order of spotting was "1, 2, M, 3, 4, 5, 6, M, 7, 8, 9, 10, M, 11, 12, H37Rv", the numbers represent samples, and M represents DNA Marker.a-3: When PCR amplification products are subjected to the first electrophoresis and Marker I is used, the gel concentration is 1%, the voltage is 150 V, and the time is 100-120 min.a-4: If the amplification product fragment is too large (>1000bp) and needs to be electrophoresed again and Marker II is used, the gel concentration is 0.8%, the voltage is 150V and the time is 150 minutes.b: Gluing as well as the electrophoresis process:PCR amplification products were electrophoresed using a 1% agarose gel.To prepare 1% agarose gel, 12×12 cm gel tray was used to make the gel, each gel was 80 ml.b-1: Weigh 0.8g of agarose, add 80ml of 0.5×TBE, weigh it on the balance and put it into the microwave oven, heat it on high for 2-3 minutes to make the agarose dissolve completely, shake it well, and observe it as a homogeneous and transparent solution without particles, then weigh it again on the balance and make up the appropriate amount of double-distilled water to keep the concentration of the gum unaffected.b-2: When the melted gel was cooled to about 55°C add 4 µl of ethidium bromide (10ug/ml) and gently swirl to mix well. The gel was made with an 18-tooth comb and the warm gel was poured into a 12 × 12 cm gel tray.b-3: Allow the gel to completely set (40 minutes at room temperature), carefully pull out the comb, remove the tray, and place it in the electrophoresis tank. Add 0.5× TBE buffer to the electrophoresis tank, not exceeding the gel surface by 1-2mm.b-4: Sample electrophoresis: add 12 samples to each gel (the topmost wells are not sampled), add 3-5µl PCR products to each well, and at the same time add three 5µl DNA MarkerⅠ to each gel. The voltage is 150V and the electrophoresis time is 100-120 minutes. This step is the key to the accuracy of the final readings of each point, and needs to be operated uniformly according to this standard.b-5: Some loci have amplification products greater than 1000bp in clinical strains, and these amplification products were then electrophoresed using 0.8% agarose gel, with DNA Marker II added as a control for the band size, voltage 150V, electrophoresis time 150 minutes.4) Results display:5) Analysis of results:a. If the genotypes of the three highly variable loci are also the same in different strains, they can be identified as clustered strains;b. If the high variant readings are highly similar, i.e., only 1-2 high variant sites are different, they need to be combined with epidemiologic data to identify if they are clustered strains;c. If all 3 high variant loci are genotypically discordant, identify as a single strain.Appendix 1: Rules for reading VNTR lociAppendix 2: VNTR locus repeat unit readout table... Read More |