| Description | Inquire | When apoptosis occurs, some DNA endonucleases will be activated. These endonucleases will cut off genomic DNA between nucleosomes and produce 180 bp-200 BP DNA fragments, which appear as a specific ladder pattern in agarose gel electrophoresis. When double strand or single strand breaks occurWhen apoptosis occurs, some DNA endonucleases will be activated. These endonucleases will cut off genomic DNA between nucleosomes and produce 180 bp-200 BP DNA fragments, which appear as a specific ladder pattern in agarose gel electrophoresis. When double strand or single strand breaks occur in genomic DNA, a large number of sticky 3'-oh ends will be generated, which can interact with YF under the catalysis of deoxyribonucleotide terminal transferase (TDT) ®/ CY dUTP binding can directly detect apoptotic cells by fluorescence microscopy or flow cytometry. This kind of method is called terminal deoxynucleotidyl transferase mediated nick end labeling (TUNEL). Because normal or proliferating cells have almost no DNA breaks, there is no 3'-oh formation and they can rarely be stained. TUNEL method can stain intact single apoptotic nuclei or apoptotic bodies in situ, can accurately reflect the typical biochemical and morphological characteristics of apoptosis, and can detect a very small number of apoptotic cells, so it is widely used in the study of apoptosis. This kit has a wide range of applications and can be used to detect apoptosis in frozen or paraffin sections, as well as cultured adherent cells or suspended cells. It can selectively detect apoptotic cells, but not necrotic cells or cells with DNA strand breaks caused by irradiation and drug treatment. This kit detects cell apoptosis with a short time-consuming, one-step staining reaction and can be detected after washing.Component： Instruction： Experimental materials (self provided)PBS buffer (1 x, pH~7.4). 0.2% Triton X -100 (PBS formulation). 0.1% Triton X -100 (PBS formulation, containing 5 mg/mLBSA)4% paraformaldehyde (prepared with PBS)Immunohistochemical penDewaxing solvent (paraffin section sample)Related reagents for paraffin section processingAnti fluorescence quenching and sealing agent. ddH2Oexperimental design. A. Positive control:Prepare positive control slides using DNaseI treatment. DNaseI can digest single or double stranded DNA and expose the 3 '- OH end, artificially causing cell apoptosis. One experiment per time is sufficient. (To verify if there are any issues with the experimental operation and reagent kit)B. Negative control:Use TUNEL Reaction Buffer without TdT Enzyme and replace TdT Enzyme with ddH2O. (Mainly to exclude non-specific staining caused by cell apoptosis, operational processes, and other reasons; and to adjust the exposure intensity of the shooting.)C. Experimental processing group.The experimental group operated normally according to the instructions.D. Experimental control group.The experimental group operated normally according to the instructions.Experimental steps1. Sample preparation:(1) For adherent cells or cell smearsa. Clean once with PBS.Note: If you are concerned that the cells on the cell smear may not adhere firmly, you can dry the sample to make the cells adhere more firmly.b. Fixation: Add an appropriate amount of 4% paraformaldehyde (prepared with PBS) and fix at 4 ℃ for 30 minutes. Clean twice with PBS.c. Translucency: Add an appropriate amount of 0.2% Triton X -100 (prepared with PBS) and let it penetrate at room temperature for 20 minutes. Clean twice with PBS.d. Step 2: TUNEL reaction.(2) For suspended cells or cell suspensionsa. Collect cells (3-5 x 106 cells), centrifuge at 1000 rpm for 5 minutes, and wash twice with PBS.b. Fixation: Add an appropriate amount of 4% paraformaldehyde (prepared with PBS) and resuspend the cells thoroughly. Fix at 4 ℃ for 30 minutes. Centrifuge at 2000 rpm for 5 minutes and clean twice with PBS.c. Translucency: Add an appropriate amount of 0.2% Triton X -100 (prepared with PBS) and let it penetrate at room temperature for 20 minutes. Centrifuge at 2000 rpm for 5 minutes and clean twice with PBS.d. Step 2: TUNEL reaction.(3) Paraffin tissue sectioninga. Dewaxing and hydration: Place the sliced samples sequentially in xylene I (10 min) → xylene II (10 min) → 100% ethanol I (5 min) → 100% ethanol II (5 min) → 95% ethanol (5 min) → 90% ethanol (5 min) → 80% ethanol (5 min) → 70% ethanol (5 min) → ddH2O rinse for 5 min, rinse twice.Note: Xylene is toxic and volatile. Please perform this operation in a fume hood.b. Use filter paper to dry the liquid around the sliced sample, and circle the sample contour with an immunohistochemical pen for downstream transparency and labeling.Note: If it is found that the contour circle of immunohistochemistry strokes is damaged in subsequent experimental operations, it needs to be redrawn in a timely manner.c. Transparency: Dilute 2 mg/mL of ProteinaseK solution with PBS in a ratio of 1:100 to a final concentration of 20 µ g/mL. Add 100 µ L dropwise to each sample to cover all sample areas. Incubate at 20-37 ℃ for 20 minutes.Note: Protein K can penetrate the cell membrane and nuclear membrane, allowing subsequent staining reagents to fully enter the nucleus for reaction and improve labeling efficiency. An excessively long incubation time increases the risk of tissue slices falling off the carrier film during subsequent washing steps, while a too short incubation time may result in insufficient permeability treatment and affect labeling efficiency. To obtain better results, the concentration, incubation time, and temperature of Protein K need to be optimized according to different types of tissue samples.d. Wash the slices twice with PBS, each time for 5 minutes. Use filter paper to remove excess liquid, and place the processed sample in a wet box to keep it moist.Note: Protein K must be washed thoroughly in this step, otherwise it will seriously interfere with subsequent labeling reactions.e. Step 2: TUNEL reaction.(4) Frozen tissue sectionsa. Fixation: Take out frozen sections and warm them back to room temperature. Add an appropriate amount of 4% paraformaldehyde (prepared with PBS) and fix at room temperature for 30 minutes. Wash twice with PBS for 10 minutes each time.Note: If you are concerned that formaldehyde cleaning may not be clean enough, it may affect the final dyeing effect. After formaldehyde fixation is completed, an appropriate amount of 2 mg/mL glycine can be added and washed for 10 minutes to neutralize the residual fixing solution, and then PBS cleaning can be carried out.b. Use filter paper to dry the liquid around the sliced sample, and circle the sample contour with an immunohistochemical pen for downstream transparency and labeling.Note: If it is found that the contour circle of immunohistochemistry strokes is damaged in subsequent experimental operations, it needs to be redrawn in a timely manner.c. Transparency: Dilute 2 mg/mL of ProteinaseK solution with PBS in a ratio of 1:100 to a final concentration of 20 µ g/mL. Add 100 µ L dropwise to each sample to cover all sample areas. Incubate at 20-37 ℃ for 20 minutes.Note: Protein K can penetrate the cell membrane and nuclear membrane, allowing subsequent staining reagents to fully enter the nucleus for reaction and improve labeling efficiency. An excessively long incubation time increases the risk of tissue slices falling off the carrier film during subsequent washing steps, while a too short incubation time may result in insufficient permeability treatment and affect labeling efficiency. To obtain better results, the concentration, incubation time, and temperature of Protein K need to be optimized according to different types of tissue samples.d. Wash the slices twice with PBS, each time for 5 minutes. Use filter paper to remove excess liquid, and place the processed sample in a wet box to keep it moist.Note: Protein K must be washed thoroughly in this step, otherwise it will seriously interfere with subsequent labeling reactions.e. Step 2: TUNEL reaction.(5) Positive treatment (only the positive control is subjected to this step, and other samples are directly subjected to the TUNEL reaction step)a. Dilute 10 x DNase I Buffer with ddH2O in a ratio of 1:10 to 1 x DNase I Buffer for later use.b. Drip 100 µ L of 1xDNase I Buffer onto the processed sample, covering all sample areas, and equilibrate at room temperature for 5 minutes.c. Dilute DNase I (2 U) with 1 x DNase I Buffer at a ratio of 1:100/ µ L) A working solution with a final concentration of 20 U/mL.d. Discard the buffer and add 100 µ Incubate DNase I working solution with a concentration of 20 U/mL at room temperature for 10 minutes.e. Discard DNase I working solution and clean twice with PBS.f. Step 2: TUNEL reaction.2. TUNEL reaction(1) Prepare TUNEL reaction solution (ready to use):/1 sample5sample10 sampleTdT enzyme1 µL5 µL10 µLYF®488/555/594/640 TUNEL Reaction Buffer49 µL245 µL490 µLTUNEL Total volume of reaction solution50 µL250 µL500 µL(2) For adherent cells, cell smears, or tissue sectionsa. Add 50 to each sample µ L TUNEL reaction solution, evenly cover the sample with the reaction solution. The appropriate time for dark incubation at 37 ℃ (recommended staining time for cells is 30 minutes to 1 hour, and tissue staining time is 2 hours).Note: 50 µ L TUNEL reaction solution is suitable for smear, slicing, or 96 well plates (other different well plates can adjust the volume of TUNEL reaction solution appropriately to cover cells). If the sample to be tested is a smear, slice, or in a 24 well plate, 12 well plate, or 6 well plate, anti evaporation film can be used, or self sealing bags or other appropriate materials can be used to cut circular plastic sheets slightly smaller than the holes. After adding TUNEL reaction solution dropwise, cover the sample to prevent the evaporation of TUNEL reaction solution and make the TUNEL reaction solution evenly cover the sample.b. Discard the TUNEL reaction solution, wash twice with PBS, and then wash three times with 0.1% Triton X -100 (PBS preparation, containing 5 mg/mL BSA) for 5 minutes each time. This way, free unreacted markers can be removed cleanly.c. (Optional) Add an appropriate concentration of 5 to each sample µ DAPI staining solution with a concentration of g/mL, incubated at room temperature in dark for 5 minutes. After staining, discard DAPI staining solution and wash twice with PBS for 5 minutes each time.d. (Optional) Slice sealing: Add 50 drops to each sample µ L anti fluorescence quenching sealing agent (anti fluorescence quenching sealing agent may not be suitable for certain dyes, it is recommended to conduct pre experimental testing for compatibility before the experiment), cover the cover glass, gently tap the cover glass with the blunt end of tweezers to remove bubbles and ensure complete sealing.e. Use filter paper to remove excess liquid and add 100 to the sample area µ Keep the sample moist with PBS and immediately observe under a fluorescence microscope.(3) For suspended cells or cell suspensionsa. Add 50 to each sample tube µ Gently resuspend cells in LTUNEL reaction solution and incubate at 37 ℃ in the dark for 30-1 hour. Gently resuspend cells with a micropipette every 15 minutes.b. Centrifuge at 2000 rpm for 5 minutes, discard TUNEL reaction solution, and wash twice with 0.1% Triton X -100 (PBS preparation, containing 5 mg/mLBSA) for 5 minutes each time. This way, free unreacted markers can be removed cleanly.c. Add 100 to each sample tube µ L concentration is 5 µ DAPI staining solution with a concentration of g/mL, incubated at room temperature in dark for 5 minutes.d. Join 400 µ L PBS resuspended cells and immediately detected with a flow cytometer or observed under a fluorescence microscope after smearing.Matters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. when the staining background is heavy or non-specific staining is obvious, the staining time can be appropriately reduced. 3. it is recommended to add negative control and positive control groups during the experiment. 4. please wear mask and gloves when using component A. if it contacts the skin, please wash it with plenty of water immediately. 5. fluorescent dyes have quenching problems. Please try to avoid light to slow down fluorescence quenching. 6. for your safety and health, please wear experimental clothes and disposable gloves.Product parameters：490/515 nm；Scope of application：Late apoptosis detection, TUNEL Kit... Read More | Inquire | Live & deadtm animal cell viability / toxicity detection kit (calcein am, ethd-i) is a kit that provides double fluorescent staining for the detection of animal cell death and survival. The two probes in the kit can respectively measure the activity of cellular lactonase and the integrity of Live & deadtm animal cell viability / toxicity detection kit (calcein am, ethd-i) is a kit that provides double fluorescent staining for the detection of animal cell death and survival. The two probes in the kit can respectively measure the activity of cellular lactonase and the integrity of plasma membrane to reflect cell viability. The kit can be used for fluorescence microscopy, flow cytometry, microplate reader and other fluorescence detection systems. This kit can be applied to most eukarYOtic mammalian cells, including some tissues with adherent nuclei, but it is not applicable to fungi and yeast. Compared with trypan blue, the kit is faster, safer and more sensitive.Component： Product parameters：Calcein am: ex/em = 494 / 517 nm; Ethd-i: ex/em = 528 / 617 nm (bound DNA)Usage:Fluorescence microscopy detection1. Prepare working fluidPreparation 2 µ M Calcein AM and 4 µ M EthD-I staining solution: Remove the original solution of Calcein AM and EthD-I and restore them to room temperature. Add 20 µ L 2 mM EthD-I and 5 µ Mix 4 mM Calcein AM with 10 mL PBS or other serum-free buffer or culture medium, vortex well. The above working solution can be directly used for cell staining.Note: The aqueous solution of Calcein AM is easily hydrolyzed and should be used up every day. The concentration selection of Calcein AM and EthD-I varies depending on the type of cell used, with a recommended concentration range of 0.1-10 µ M.2. Prepare cells and conduct experiments(1) For adherent cells, they can be washed 2-3 times with 1 × PBS before staining. For suspended cells, centrifuge at room temperature of 250-1000 × g for 5 minutes and collect cells for staining.(2) Wash the cells thoroughly 2-3 times with 1 × PBS to remove residual esterase activity.(3) For adherent cells, add sufficient amount of Calcein AM/EthD-I staining solution. For suspended cells, add an appropriate amount of staining solution to control the cell density between 1-5 × 105/mL.(4) Incubate at room temperature in dark for 15-20 minutes (if the working solution concentration is high or the incubation temperature is high, the incubation time should be appropriately reduced).(5) Observe the labeled cells under a fluorescence microscope.Flow cytometry detection1. Remove the reagent and restore it to room temperature.2. Preparation 2 µ M Calcein AM and 4 µ M EthD-I staining solution: Take out the original solution of Calcein AM and EthD-I, and restore to room temperature. Add 20 µ L 2 mMEthD-I and 5 µ Vortex mix 4 mM Calcein AM with 10 mL PBS or other serum-free buffer or culture medium. The working fluid can directly stain cells.3. Wash cells thoroughly 2-3 times with 1 × PBS.4. Suspend cells with 0.5 mL of staining solution and control the cell density to 1-5 × 105/mL.Note: It is recommended to prepare two additional cell samples, each containing only one dye (Calcein AM and EthD-I), for compensatory regulation of flow cytometry single staining; Prepare another cell sample containing only buffer solution (which should be consistent with the buffer used to prepare Calcein AM and EthD-I detection working solutions) as a negative control for flow cytometry analysis.5. Incubate at room temperature in dark for 15-20 minutes.6. Within 1-2 hours, cell activity was detected by flow cytometry. Calcein AM can be excited by a 488 nm laser, with fluorescence emission spectra detected at around 530 nm and EthD-I emission spectra at around 610 nm.Note: When using the cell circle gate, attention should be paid to excluding cell debris and using a single staining tube to regulate compensation. Double staining tube flow cytometry should obtain two relatively independent cell populations: a live cell population displaying green fluorescence and a dead cell population displaying red fluorescence.ELISA reader detection1. Cultivate an appropriate amount of adherent or suspended cells in a 96 well black ELISA plate.Note: Dead cells can be obtained by treating cells with 1% saponin or 0.1-0.5% digitalis saponin for 10 minutes.2. Preparation 2 µ M Calcein AM and 4 µ M EthD-I staining solution:Remove the original solutions of Calcein AM and EthD-I and restore them to room temperature. Add 20 µ L 2 mM EthD-I and 5 µ Mix 4 mM Calcein AM 10 mL PBS or other serum-free buffer or culture medium, vortex well.Note: (1) 10 mL of staining solution is sufficient to stain a 96 well plate, and the volume of the staining solution can be adjusted according to experimental needs. The concentrations of Calcein AM and EthD-I can range from 0.1 to 10 µ Explore between M.(2) The aqueous solution of Calcein AM is easily hydrolyzed and should be used up every day. EthD-I working solution can be stored at -20 ℃ for at least one year.3. Wash the cells thoroughly with 1 × PBS to remove residual esterase activity. For adherent cells, add 100 to each well µ Wash cells with PBS. For suspended cells, add 100 µ Resuspend cells with L PBS and centrifuge to remove the supernatant. Repeat the above operation.4. Add 100 to each hole µ L PBS.5. Add 100 to each hole µ L staining solution, making the total volume of each well 200 µ L. The final concentration of Calcein AM is 1 µ M. The final concentration of EthD-I is 2 µ M. Gently shake the culture plate to evenly cover the cells with the liquid.Incubate at room temperature in dark for 30-45 minutes.Note: The optimal incubation time varies for different cells, with 30 minutes as the initial incubation time. Subsequently, the staining time can be adjusted and optimized according to the actual staining effect to obtain a more ideal staining effect.7. Enzyme reader detection. When the ELISA reader is set to fluorescein, it can detect Calcein AM; When the ELISA reader is set to rhodamine or Texas Red, EthD-I can be detected. Select the optimal emission and excitation wavelengths based on spectral characteristics.Note: By comparing the relative fluorescence values (RFU) measured between the sample group and the control group, the changes in the number of dead and live cells can be obtained. Another method of data analysis is also provided below.The following method can calculate the ratio of live cells to dead cells in a certain region. The required samples include dead cell control group, live cell control group, and the sample group to be tested. Dead cells can be obtained by treating cells with 1% saponin or 0.1-0.5% digitalis saponin for 10 minutes.1. Prepare staining solution and follow the above steps to stain cells. Additionally, prepare 1 mL and 2 mL separately µ M Calcein AM and 4 µ M EthD-I solution, stain the control group according to the following instructions. For the following groups of cells or cell-free groups, it is necessary to maintain complete consistency in cell count, detection of working solution concentration, incubation time, and incubation temperature.2. Measurement of sample group and control group:A. The measured values of the sample group at 645 nm are denoted as Calcein AM and EthD-I=F (645) sam.B. The measured values of the sample group at 530 nm are denoted as Calcein AM and EthD-I=F (530) sam.C. The measurement value of dead cell EthD-I single staining control group at 645 nm is denoted as EthD-I=F (645) maxD. The measurement value of dead cell Calcein AM single staining control group at 645 nm is recorded as Calcein AM=F (645) minE. The measurement value of live cell EthD-I single staining control group at 530 nm is recorded as EthD-I=F (530) min.F. The measurement value of live cell Calcein AM single staining control group at 530 nm is denoted as Calcein AM=F (530) max.G. A blank control well without cells (with or without dye), the detection value at 530 nm is recorded as F (530) 0.H. A blank control well without cells (with or without dye), the detection value at 645 nm is recorded as F (645) 0.3. Calculate the ratio of dead cells to live cells based on measurement data:%Live Cells=(B-E) ÷ (F-E)%Dead Cells=(A-D) ÷ (C-D)Determine the ratio of live cells to dead cells in a certain areaBy creating fluorescence spectral standard curves at 530 nm and 645 nm, the number of dead and live cells can be determined, and the fluorescence intensity of each dye is linearly related to the number of dead or live cells in the sample.Matters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. phenol red or serum may interfere with the detection of this kit. 3. fluorescent dyes have quenching problems. Please try to avoid light during experimental operation to slow down fluorescence quenching. 4. for your safety and health, please wear experimental clothes and disposable gloves.Scope of application：Dead and live cell staining (animal)... Read More | Products contentN665989Component240 TStorageN665989AIndex N501 Primers for Illumina240 µL-20℃. Avoid freeze/ Thaw cycle.N665989BlIndex N901-N924 Primers for Illumina24×10 µL-20℃. Avoid freeze/ Thaw cycle.Note: The amount of individual primers used is 1 µl, each N7-endProducts contentN665989Component240 TStorageN665989AIndex N501 Primers for Illumina240 µL-20℃. Avoid freeze/ Thaw cycle.N665989BlIndex N901-N924 Primers for Illumina24×10 µL-20℃. Avoid freeze/ Thaw cycle.Note: 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 IlluminaIndex N901-N996 Primer for Illumina... Read More |