| 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.Composition: Composition 20T 50T A. aladdin®640 TUNEL Reaction Buffer 1 mL 2 ×1.25 mL B. TdT Enzyme 20 µL 50 µL C. Proteinase K (2 mg/mL) 40 µL 100 µL D. DNase I (2 U/µL) 5 µL 13 µL E. 10 ×DNase I Buffer 100 µL 260 µL Product parameters：642/662 nm； 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.Scope of application：Late apoptosis detection, TUNEL Kit... Read More | Product content C665709Component50 TStorageC665709ABuffer CL45 mLRTC665709BBuffer CB (concentrate)60 mLRTC665709CBuffer GW1 (concentrate)13 mLRTC665709DBuffer GW2 (concentrate)15 mLRTC665709EBuffer EBL10 mLRTC665709FProteinase K100 mgRTC665709GProteinase K Storage Buffer5 mLRTC665709HSpin Columns DFProduct content C665709Component50 TStorageC665709ABuffer CL45 mLRTC665709BBuffer CB (concentrate)60 mLRTC665709CBuffer GW1 (concentrate)13 mLRTC665709DBuffer GW2 (concentrate)15 mLRTC665709EBuffer EBL10 mLRTC665709FProteinase K100 mgRTC665709GProteinase K Storage Buffer5 mLRTC665709HSpin Columns DF with Collection Tubes50 EA2-8℃C665709ICentrifuge Tubes (L-1.5 mL)50 EART Product IntroductionThis kit is suitable for the extraction of free DNA from fresh or frozen serum, plasma, lymph fluid and other cell-free body fluids.This kit adopts centrifugal adsorption columns that can specifically bind nucleic acids and a unique buffer system.After the sample is lysed, the free DNA binds to the silica gel membrane under high salt conditions, and the free DNA elutes from the silica gel membrane at low salt and high pH. The product can handle liquid samples of 0.1-1 ml, and the elution volume of the configured high-efficiency micro adsorption column can be as low as 20 µl. The purified DNA is of high yield and quality, with maximum removal of proteins, pigments, lipids, and other inhibitors, and the rate of free DNA yield is highly dependent on the type of samples, storage conditions, time, and inter-individual variations. The quality of free DNA obtained from purification is stable and reliable, and can be directly used in molecular biology experiments such as PCR, fluorescence quantitative PCR and second generation sequencing.Self-contained reagents: anhydrous ethanol, isopropanol.Pre-experiment Preparation and Important NotesAdd 5 ml of Proteinase K Storage Buffer to Proteinase K to dissolve it and store it at -20℃. Do not leave the prepared Proteinase K at room temperature for a long time.Repeated freezing and thawing of the sample should be avoided, as this can lead to a decrease in extraction.This kit can extract 0.1-1 ml of liquid samples.Before use, please check Buffer CL, Buffer CB for crystallization or precipitation, if there is any crystallization or precipitation, please re-dissolve Buffer CL, Buffer CB by incubation at 56℃ in a water bath.Before first use isopropyl alcohol should be added to Buffer CB according to the instructions on the reagent bottle label, mixed well, and labeled on the reagent bottle label.Before the first use, anhydrous ethanol should be added to Buffer GW1 and Buffer GW2 according to the instructions on the label of the reagent bottle, mixed well, and labeled on the label of the reagent bottle.Preheat the water bath to 60°C before starting the experiment.The elution buffer Buffer EBL can be preheated to 60°C and used.Operation stepsAdd 20 µl of Proteinase K to the centrifuge tube (supplied).Add 200 µl of serum/plasma sample.Note: When the sample volume exceeds 200 µl, please increase the amount of Proteinase K, Buffer CL and Buffer CB reagents in equal proportions, and the specific amount of reagents added can be referred to the attached table.3. Add 160 µl Buffer CL, mix upside down and shake vigorously for at least 30 seconds.4. Incubate at 60°C for 30 minutes, during which time mixing was inverted several times.Note: Incubation of 200µl serum/plasma samples at 60°C for 10-15 minutes is sufficient.Add 360 µl of Buffer CB (check for addition of isopropanol before use) and shake until thoroughly mixed.Ice bath for 5 minutes and centrifuge briefly to concentrate the liquid on the walls and wall caps to the bottom of the tube.Add all of the solution obtained in step 6 to the adsorption columns (Spin Columns DF) that have been loaded into the collection tubes, and 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 solution from the collection tubes, and put the columns back into the collection tubes.Add 500µl of Buffer GW1 to the adsorbent column (check that anhydrous ethanol is added before use),centrifuge the column at 12,000rpm for 30 seconds, pour off the waste liquid in the collection tube, and put the adsorbent column back into the collection tube.Add 750 µl Buffer GW2 to the adsorbent column (check that anhydrous ethanol is added before use), centrifuge at 12,000 rpm for 30 seconds, pour off the waste liquid in the collection tube, and put the adsorbent column back into the collection tube.10. Add 750 µl of anhydrous ethanol to the adsorbent column and centrifuge at 12,000 rpm for 30 s. Pour off the waste liquid in the collection tube and put the adsorbent column back into the collection tube.11. 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 the subsequent enzymatic reaction.12. Place the adsorption column in a new centrifuge tube, add 20-100 µl Buffer EBL or sterilized water to the middle part of the adsorption column overhanging the column, leave it at room temperature for 2-5 minutes, centrifuge at 12,000 rpm for 1 minute, collect the DNA solution, and store the DNA at -20℃.Note: 1) If the downstream experiment is sensitive to pH, you can use sterilized water for elution. The pH value of the eluent has a great influence on the elution efficiency, if water is used as the eluent should ensure that its pH value is 7.0-8.5 (you can use NaOH to adjust the pH value of water to this range), and the elution efficiency is not high when the pH value is lower than 7.0.2) Preheat the elution buffer BufferEBL to 60℃ and use it, and incubate it at room temperature for 5 minutes before centrifugation to increase the yield.3) If the final concentration of DNA is to be increased, the resulting solution can be reintroduced into the adsorption column and left at room temperature for 2-5 minutes and centrifuged at 12,000 rpm for 1 minute.4) Because DNA preserved in water will be affected by acidic hydrolysis, for long-term storage, it is recommended to elute it with Buffer EBL and store it at -20℃.Table: Recommended reagent additions for different sample sizes... Read More | DescriptionRefer to the product′s Certificate of Analysis for more information on a suitable instrument technique. Contact Technical Service for further support | Inquire |