| 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 occur in 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 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 sample 5 sample 10 sample TdT enzyme 1 µL 5 µL 10 µL YF®488/555/594/640 TUNEL Reaction Buffer 49 µL 245 µL 490 µL TUNEL Total volume of reaction solution 50 µL 250 µL 500 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：590/617nm； Scope of application：Late apoptosis detection, TUNEL Kit... Read More | DescriptionCAR10 is a kit that contains a selection of 10 carbohydrates/sugars: Arabinose, Fructose, Galactose, Glucose, α-Lactose, Maltose, Mannose, Ribose, Sucrose and Xylose, which may be used for general research, as reagents or as reference compounds in analytical procedures | Inquire | This product is a cDNA first strand synthesis kit specially prepared for the first step experiment of two-step RT-PCR. The reverse transcriptase used in this kit is a novel and efficient reverse transcriptase that utilizes E. coli engineered bacteria for recombination and expression. It removes This product is a cDNA first strand synthesis kit specially prepared for the first step experiment of two-step RT-PCR. The reverse transcriptase used in this kit is a novel and efficient reverse transcriptase that utilizes E. coli engineered bacteria for recombination and expression. It removes RNase H activity and enhances its thermal stability. It can synthesize cDNA first strands using extremely low amounts of total RNA or mRNA, with an initial sample size as low as pg level. SuperRT reverse transcriptase has strong affinity for RNA and can read RNA templates with high GC content and complex secondary structures, obtaining high yields of cDNA. This product contains all the reagents required for reverse transcription from RNA templates to cDNA first strand, including Super RT efficient reverse transcriptase, reaction buffer, primers, dNTP, etc. It is simple and convenient to use. This system has high compatibility with subsequent PCR and quantitative PCR experiments, and is suitable for various DNA polymerase reactions. S665657 Component 100 T Storage S665657A SuperRT, 200 U/µL 100 µL -20℃. Avoid freeze/thaw cycle. S665657B 5×SuperRT Buffer 500 µL -20℃. Avoid freeze/thaw cycle. S665657C Primer Mix 240 µL -20℃. Avoid freeze/thaw cycle. S665657D dNTP Mix, 2.5 mM Each 500 µL -20℃. Avoid freeze/thaw cycle. S665657E RNase-Free Water 1 mL -20℃. Avoid freeze/thaw cycle.Product features:·Efficient reverse transcription: It has a high affinity for RNA templates, with a reverse transcription efficiency of up to 90%, and can recognize pg level templates.·Free response to complex templates: Even templates with high GC content and complex secondary structures can achieve good results without high-temperature denaturation.Notes:1. During the operation process, RNase contamination should be avoided to prevent RNA degradation or cross contamination during experiments. It is recommended to perform RNA operations in specialized areas, use specialized instruments and consumables, and have operators wear masks and disposable gloves, and frequently change gloves.2. Disposable plastic containers should be used as much as possible for experiments. If glass containers are used, they should be treated with a 0.1% DEPC (diethyl pyrocarbonate) aqueous solution at 37 ℃ for 12 hours, and sterilized under high pressure at 120 ℃ for 30 minutes before use. Alternatively, glass containers should be sterilized under dry heat at 180 ℃ for 60 minutes before use. The sterile water used in the experiment should be treated with 0.1% DEPC and then subjected to high-pressure sterilization.3. All reagents in this reagent kit should be gently mixed upside down before use, avoiding foaming as much as possible, and used after brief centrifugation. The enzymes involved should be returned to -20 ℃ as soon as possible after use to avoid repeated freeze-thaw cycles.If the initial amount of RNA is less than 50 ng, it is recommended to add RNA enzyme inhibitors (RNAsin). This kit is not provided.Usage:Note: 1 ng -5 µ g of total RNA can establish a 20 µ l reaction system. If the total RNA amount is greater than 5 µ g, please expand the reaction system proportionally.Steps for reverse transcription:1. Dissolve the RNA template, Primer Mix, dNTP Mix, SuperRT Buffer, SuperRT, and RNase Free Water and place them on ice for later use.2. Prepare a reaction system according to the following table, with a total volume of 20 µ L. Reagent 20 µlReaction system Final concentration dNTP Mix，2.5 mM Each 4 µl 500 µM Each Primer Mix 2 µl / RNA Template X µl 50 pg-5 µg SuperRT，200 U/µl 1 µl / RNase-Free Water up to 20 µl / Attention:1) If the initial amount of RNA is less than 50 ng, it is recommended to add RNA enzyme inhibitors (RNAsin). This kit is not provided.2) Primer Mix is formulated from Oligo (dT) and Random Primer. Oligo dT Primer or Gene Specific Primer can be used according to experimental needs, with a recommendation of 20 µ The reaction system Oligo dT Primer is 50 pmol, or Gene Specific Primer is 2 pmol.3. Vortex shake and mix well, briefly centrifuge to collect the solution on the pipe wall to the bottom of the pipe.Incubate at 4.42 ℃ for 30-50 minutes and 85 ℃ for 5 minutes. After the reaction is complete, centrifuge briefly and cool on ice.5. Reverse transcripts can be directly used for PCR reactions and fluorescence quantitative PCR reactions, or stored at -20 ℃ for a long time. Reagent 20 µ Final concentration of reaction system dNTP Mix, 2.5 mM Each 4 µ L 500 µ M Each Primer Mix 2 µ RNA Template X µ L 50 pg-5 µ g 5 x SuperRT Buffer 4 µ 1 x SuperRT, 200 U/ µ L 1 µ RNase Free Water up to 20 µ Lii If the reverse transcription efficiency is low, or the RNA template secondary structure is complex and the GC content is high, the following steps are recommended:1. Dissolve the RNA template, Primer Mix, dNTP Mix, SuperRT Buffer, SuperRT, and RNase Free Water and place them on ice for later use.2. Configure the reaction system according to the following table, with a total volume of 15 µ L. Reagent 20 µlReaction system Final concentration dNTP Mix，2.5 mM Each 4 µl 500 µM Each Primer Mix 2 µl / RNA Template X µl 50 pg-5 µg RNase-Free Water up to 15 µl / Note: Primer Mix is formulated from Oligo (dT) and Random Primer. Oligo dT Primer or Gene Specific Primer can be used according to experimental needs. 3. Incubate at 70 ℃ for 10 minutes and quickly ice bath for 2 minutes.4. Centrifuge briefly to collect the solution on the tube wall to the bottom of the tube.5. Continue to add the following reagents to the above reaction solution: Reagent 20 µlReaction system Final concentration 5×SuperRT Buffer 4 µl 1× SuperRT，200 U/µl 1 µl / Note: If the initial amount of RNA is less than 50 ng, it is recommended to add RNA enzyme inhibitors (RNasins). This kit is not provided. 6. Incubate at 42 ℃ for 30-50 minutes and 85 ℃ for 5 minutes.7. After the reaction is complete, centrifuge briefly and cool on ice.8. Reverse transcripts can be directly used for PCR reactions and fluorescence quantitative PCR reactions, or stored at -20 ℃ for a long time... Read More |