| 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 | The commonly used method of eukarYOtic gene expression regulation research is the detection of reporter genes, and bioluminescence is the most commonly used and effective means of reporter gene detection. Luciferase can catalyze the conversion of the substrate luciferin and emit photons. This The commonly used method of eukarYOtic gene expression regulation research is the detection of reporter genes, and bioluminescence is the most commonly used and effective means of reporter gene detection. Luciferase can catalyze the conversion of the substrate luciferin and emit photons. This product provides a rapid, sensitive and stable detection method for the expression of Renilla luciferase reporter gene in mammalian cells. Product characteristic：1.Rapid : Cell lysis was completed within 10-15 min ；2.Convenience : The reagent is easy to prepare, and the sample detection steps are simple；Instruction：1. Cell lysis ( 1 ) Remove the culture medium and gently wash with PBS ( adherent cells can be directly performed this operation, suspension cells should be centrifuged to collect cells ). Add 1 × Lysis Buffer ( diluted component A with sterile water at 4 : 1 ) according to the following scheme, and then place the culture plate on a micro-oscillator at room temperature for 15 min to fully lyse the cells. Note : The pyrolysis products can be stored at room temperature for 6 h, and can be stored at − 70 °C for a long time ( the pyrolysis products cannot be repeatedly frozen and thawed ). ( 2 ) The pyrolysis products after full pyrolysis were centrifuged at 10000-15000 rpm for 3-5 min. After centrifugation, the supernatant was moved into a new EP tube for subsequent detection. 2. Preparation of working fluid ( 1 ) Restore all components to room temperature. ( 2 ) Dilute component C into renilla luciferase working solution with component B, and the dilution method is to add 1 µL C component to 49 µL B component. 3.chemiluminescence value detection ( 1 ) According to the operation instructions of the instrument, the instrument with chemiluminescence detection function was opened, such as multifunctional microplate reader. The parameters were set, the determination time was 10 s, and the determination interval was 2 s. ( 2 ) The cell lysis products were added to the measuring tube according to the volume of 20 ~ 100 µL ( keep the same amount of samples each time ). 1 × Lysis Buffer was blank control. ( 3 ) 100 µL renilla luciferase working solution was added to determine the RLU ( Relative light unit ) value ( Shaking mixing function is recommended for microplate reader ). Note : The renilla luciferase working solution cannot be stored for a long time. It is now ready for use and is used once. Component：RenillaLuciferase Lysis Buffer；RenillaLuciferase Assay Buffer；CoelenterazineMatters needing attention：Scope of application： Matters needing attention：1.Please instantaneously centrifuge the product to the bottom of the tube before use, and then carry out subsequent experiments ; 2.Due to the influence of temperature on the enzyme reaction, the sample and reagent should be measured after reaching room temperature. 3.The strongest wavelength of bioluminescence catalyzed by renilla luciferase is 480 nm, in order to prevent interference between holes, it is recommended to use white opaque orifice plate ;4. B component is recommended to carry out small batch packing according to the experimental requirements ; 5.It is recommended to use it now to avoid repeated freezing and thawing ; 6.For your safety and health, please wear experimental clothes and wear disposable gloves. Scope of application：Study on gene expression regulation and promoter... Read More | This reagent kit is designed based on the principle that biotin and Streptavidin have a strong affinity. After the primary antibody of rabbit or mouse origin binds to the corresponding target antigen, the biotinylated antibody in this kit • • Rabbit/mouse universal secondary antibody This reagent kit is designed based on the principle that biotin and Streptavidin have a strong affinity. After the primary antibody of rabbit or mouse origin binds to the corresponding target antigen, the biotinylated antibody in this kit • • Rabbit/mouse universal secondary antibody specifically binds to the primary antibody; The biotin labeled on the secondary antibody binds to streptavidin labeled with peroxidase (HRP), forming an antigen-specific primary antibody biotinylated secondary antibody streptavidin complex labeled with HRP. HRP can catalyze substrate colorimetry, thereby inferring the presence and distribution of the tested antigen. The biotinylated secondary antibody and SA-HRP used in this reagent kit all adopt optimized labeling and purification techniques, which make their staining more sensitive and have a lower background. They are suitable for detecting formalin fixed paraffin embedded tissue sections, as well as frozen sections, cell slides, freshly prepared blood smears, etc. The rabbit/mouse universal Streptavidin HRP kit is suitable for use with aladdin ready to use or concentrated antibodies. Composition：Note: This reagent kit is only suitable for IHC experiments where the primary antibody is an immune or mouse derived antibodNotes:1. Add 1 drop (approximately 50) to each slice µ l) Calculation: 3ml can make 60 slices, and 18ml can make 360 slices.2.For tissues with abundant endogenous biotin content, it is best to use endogenous biotin blockers for blocking when using this kit.3. DAB working solution is prepared and used immediately, and the prepared working solution is effective within 1 hour in the dark at 2-8 ° C.4. During the experiment, avoid drying the tissue slices, so the amount of working fluid used during each incubation step must be sufficient to ensure complete coverage of the tissue sample, and incubation should be carried out in a wet box as much as possible.5. To obtain the best experimental results, please make sure to optimize the experimental conditions and reagent dosage.6. DAB is a suspected carcinogen, please take necessary protective measures when using it. 7. This product is only for scientific research and cannot be used for human reactions or treatments.Operation steps：1. Routine processing of samples such as paraffin or frozen tissue sections or cell slides to be tested.1) Preparation for staining of tissue sections or cell slides: a. Dewaxing and hydration of paraffin sections: bake at 60 º C for 1 hour, dewaxing twice with xylene for 5 minutes each time; Then immerse in gradient ethanol (anhydrous ethanol anhydrous ethanol 95% 85% 75% ethanol) and distilled water for 5 minutes each for hydration. b. Frozen sections and cell climbing sections (or climbing sections) were soaked in 0.01 M pH 7.4 PBS and washed 3 times for 5 minutes. Then cover the tissue (or cells) with 0.1% Triton X-100 and infiltrate for 15 minutes. Wash twice with 0.01 M pH 7.4 PBS for 5 minutes.2) Antigen repair of paraffin sections: In most cases, high-pressure repair with citric acid buffer is suitable for paraffin tissue sections. Preparation of repair solution: Add 10 ml of citric acid buffer (IHC antigen repair solution, 100 x) to 1 L of deionized water, and mix well. Repair process: The repair solution is added to a high-pressure cooker, and the repaired slices are immersed in the repair solution (must have no tissue). Cover the pressure cooker cover, heat until evenly sprayed with steam, and start timing from the spraying. After 1-2 minutes, the pressure cooker leaves the heat source and cools naturally to room temperature. Remove the slices, rinse with distilled water, and rinse twice with PBS (0.01 M pH 7.4) for 3 minutes each time.2. Add an appropriate amount of Solution A white solution, which is an endogenous peroxidase blocking solution, and incubate at room temperature for 10 minutes, then rinse thoroughly with PBS.3. Add an appropriate amount of Solution B white solution dropwise, which is sealed with normal sheep serum working solution. Incubate at room temperature for 10 minutes and shake dry.4. Add an appropriate amount of primary antibody working solution (commercial ready to use antibodies or concentrated antibodies diluted in appropriate proportions) dropwise, incubate according to experimental requirements, and then rinse thoroughly with PBS.5. Add an appropriate amount of Solution C yellow solution, namely biotin labeled sheep anti rabbit/mouse secondary antibody working solution, incubate at room temperature for 10 minutes, and rinse thoroughly with PBS.6. Add an appropriate amount of Solution D red solution, which is HRP labeled streptavidin. Incubate at room temperature for 10 minutes and rinse thoroughly with PBS.7. Preparation of DAB color working solution: According to the required amount, mix DAB-A and DAB-B in a volume ratio of 1:19 to obtain DAB color working solution. Alternatively, one drop (approximately 50) can be added per milliliter of reagent B µ l) Reagent A, mix well.8. Color development: Add an appropriate amount of DAB color development working solution to the tissue section or cell slide that needs to be developed, and the color development time is generally 1-5 minutes. Observe and control the color development time under a microscope. When the optimal color development effect is achieved, rinse with tap water to terminate the color development. The colored slices are re stained, dehydrated and transparent, and can be stored for a long time after sealing... Read More |