| 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 | Glycogen and starch generate glucose-1-phosphate (1PG/G1P) during the process of phosphohydrolysis. This reagent kit provides a simple, sensitive, and rapid determination method: Glucose-1-phosphate (1PG/G1P) is reduced from NADP+to NADPH by the sequential action of phosphoglucose mutase and Glycogen and starch generate glucose-1-phosphate (1PG/G1P) during the process of phosphohydrolysis. This reagent kit provides a simple, sensitive, and rapid determination method: Glucose-1-phosphate (1PG/G1P) is reduced from NADP+to NADPH by the sequential action of phosphoglucose mutase and phosphoglucose dehydrogenase. The content of glucose-1-phosphate (1PG/G1P) in the sample can be calculated by detecting the increase in NADPH at 340nm.Composition and preparation of reagent kit: Reagent name Specifications Save requirements Remarks Extraction solution Liquid 100mL x 1 bottle 4 ℃ storage / Reagent 1 Powder mg x 1 tube 4 ℃ storage Shake or centrifuge the reagent a few times before use to make it fall to the bottom, then dissolve it in 1.2mL of distilled water for later use. Reagent 2 Powder mg x 1 tube Store at -20 ℃ Shake or centrifuge the reagent a few times before use to make it fall to the bottom, then dissolve it in 1.2mL of distilled water for later use. Reagent 3 Liquid 16mL x 1 bottle 4 ℃ storage / Reagent 4 Powder mg x 1 tube Store at -20 ℃ Shake or centrifuge the reagent a few times before use to make it fall to the bottom, then add 1 Dissolve 1mL of distilled water for later use. TRC 1 powder 4 ℃ storage Only used to identify whether the reagents in the kit are normal (not involved in result calculation). Usage: Use a pre standard tube (GIP) to shake the powder a few times until it falls to the bottom, then add 0.5mL of distilled water and mix well to dissolveDilute GIP with a concentration of 4mg/mL and then dilute it four times to 1mg/mL for later use: follow the instructions in the sample addition table for the measuring tube operationRequired instruments and supplies:ELISA reader, 96 well plate, desktop centrifuge, adjustable pipette, mortar, ice and distilled water.Determination of glucose-1-phosphate (1PG/G1P) content:1. Sample preparation① Organizational sample:Suggest weighing around 0 1g of tissue, add 1mL of extraction solution, and homogenize in an ice bath. Centrifuge at 12000rpm, 4 ℃ for 10 minutes, take the supernatant, and place it on ice for testing.[Note]: If the sample size is increased, it can be extracted in a ratio of tissue mass (g) to extraction solution volume (mL) of 1:5-10.② Bacterial/cellular samples:Collect bacteria or cells into a centrifuge tube first, centrifuge and discard the supernatant; Take about 5 million bacteria or cells and add them to 1mLExtract solution, sonicate bacteria or cells (ice bath, power 200W, sonication for 3s, interval 10s, repeated 30 times); Centrifuge at 12000rpm at 4 ℃ for 10 minutes, take the supernatant, and place it on ice for testing.[Note]: If the sample size is increased, extraction can be carried out in a ratio of 500-1000:1 of bacteria/cell quantity (104) to extraction solution (mL).③ Liquid sample: direct detection.2. Machine testing:① Preheat the enzyme-linked immunosorbent assay (ELISA) reader for at least 30 minutes and adjust the wavelength to 340nm.② Thaw the reagent to room temperature (25 ℃);③ Add reagents to the 96 well plate in the following order according to the table:② Thaw the reagent to room temperature (25 ℃);③ Add reagents to the 96 well plate in the following order according to the table: Reagent name (µL） Measurement tube Blank tube (only done once) Reagent 1 10 10 Reagent 2 10 10 Reagent 3 150 170 Sample 20 / Mix well, incubate at room temperature (25 ℃) for 20 minutes, and then read A1 at 340nm (if the A value continues to increase, the incubation time needs to be extended until the absorbance value remains unchanged within 2 minutes). Reagent 4 10 10 Mix well, incubate at room temperature (25 ℃) for 20 minutes, and then read A2 at 340nm (if the A value continues to increase, the incubation time needs to be extended until the absorbance value remains unchanged within 2 minutes). Δ A=(A2-A1) measurement - (A2-A1) blank.[Note] 1 If the difference in Δ A is hovering around zero, the sample size V1 can be increased (such as increasing to 50 µ L, the three phases of the reagent should be reduced while keeping the total volume unchanged), or the sample sampling mass W can be increased. The changed V1 and W need to be substituted into the formula for recalculation.If the A2 value exceeds 1.2, the amount of sample added V1 can be reduced (such as to 10 µ L, the three-phase reagent should be increased while keeping the total volume unchanged), or the sample can be diluted with distilled water (keeping the sample addition system unchanged), and the changed V1 and D need to be substituted into the formula for recalculation.Result calculation:1. Calculated by sample weight:1PG/G1P content (µ g/g fresh weight)=[(Δ A ÷ (ε× d) × V2 × 106 × MR] ÷ (W × V1 ÷ V) × D=836 × Δ A ÷ W × D2. Calculated by the number of cells:1PG/G1P content (µ g/104 cell)=[(Δ A ÷ (ε× d) × V2 × 106 × MR] ÷ (500 × V1 ÷ V) × D=1.7 × Δ A × D. 3. Calculated by liquid volume:1PG/G1P content (µ g/mL)=[(Δ A ÷ (ε× d) × V2 × 106 × Mr] ÷ V1=836 × Δ A ε---NADPH Molar extinction coefficient，6.22×103 L/mol/cm； d---96 Orifice plate optical diameter，0.5cm； V---Add volume of extraction solution，1 mL； V1---Add sample volume，0.02mL V2---Total reaction volume；0.2mL=2×10-4L； W---Sample quality，g； Mr---Glucose-1-phosphate（1PG/G1P）Molecular weight；260； 500---Number of cells, in millions； D---Dilution ratio，Undiluted is 1。 /... Read More | Product introduction：Griess reagent can be used for spectrophotometric detection of nitrite. The reagent contains two chemicals, sulfonic acid and n- (1-naphthyl) ethylenediamine. Under acidic conditions, sulfamic acid is converted into diazonium salt by nitrite, which can form a highly Product introduction：Griess reagent can be used for spectrophotometric detection of nitrite. The reagent contains two chemicals, sulfonic acid and n- (1-naphthyl) ethylenediamine. Under acidic conditions, sulfamic acid is converted into diazonium salt by nitrite, which can form a highly colored azo dye with n- (1-naphthyl) ethylenediamine. This dye can be detected at 548 nm: because no is extremely unstable, it is oxidized to form nitrite and nitrate. Griess indirectly reflects the content of no by detecting the content of nitrite.Matters needing attention：1. before using Griess reagent, return it to room temperature and check the solution for precipitation. If Griess reagent I contains sediment when taken out, it can be placed in a 37 ℃ water bath until the sediment dissolves. 2. this product is potentially harmful. Avoid prolonged or repeated exposure. Avoid entering eyes, skin or clothing. Please wear lab clothes and disposable gloves for operation.Scope of application：No detectionComponent：Instruction：1.Griess Reagent I and II were taken out to restore the room temperature.2.Standard dilution : The standard NaNO2 ( 1-100 µM ) was diluted with the solution used for the sample to be tested. The standard was diluted to 1 µM, 10 µM, 20 µM, 40 µM, 80 µM and 100 µM, and 100 µL standard was added to each well. If the sample concentration is too low, the range of the standard curve can be appropriately reduced ( 1 µM, 2 µM, 3 µM, 4 µM, 6 µM, 8 µM, 10 µM ).3.Sample detection :( 1 ) According to the total volume of 200 µL / hole, 100 µL / hole sample was added to the 96-well plate ; if the sample is the supernatant of the culture medium, it can be sampled directly, and if there is sediment, the supernatant should be taken after centrifugation. If the sample is a cell or tissue, it can be quickly lysed by freeze-thaw, and then centrifuged to obtain the supernatant. The volume of less than 100 µL can be diluted with diH2O or 0.9 % NaCl ( corresponding standards also need to be diluted with diH2O or 0.9 % NaCl ).( 2 ) According to 50 µL / hole, Griess Reagent I was added to each hole.( 3 ) According to 50 µL / hole, Griess Reagent II was added to each hole.( 4 ) The absorbance was measured at 540 nm. If there is no 540 nm filter, 520-560 nm filter can also be. If there is no microplate reader or a suitable filter, the concentration of nitric oxide in the sample can also be determined by visual colorimetry. A more precise concentration gradient is required for the standard when visual colorimetric... Read More | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export |