| Description | Acetate Kinase (ACK) is primarily found in microorganisms. It catalyzes the conversion of acetate and ATP to acetyl phosphate and ADP, serving as a key enzyme in bacterial carbon and energy metabolism, and plays a central role particularly in the methanogenesis metabolism of archaea.Assay Acetate Kinase (ACK) is primarily found in microorganisms. It catalyzes the conversion of acetate and ATP to acetyl phosphate and ADP, serving as a key enzyme in bacterial carbon and energy metabolism, and plays a central role particularly in the methanogenesis metabolism of archaea.Assay PrincipleACK catalyzes the synthesis of Acetyl Phosphate and ADP from Sodium Acetate and ATP. Pyruvate Kinase then catalyzes the conversion of ADP and Phosphoenolpyruvate (PEP) to ATP and Pyruvate. Subsequently, Lactate Dehydrogenase catalyzes the reduction of Pyruvate by NADH to produce Lactate and NAD⁺. The rate of oxidation of NADH to NAD⁺, measured by the decrease in absorbance at 340 nm, reflects ACK activity.Component50TStorageExtraction Buffer80 mL2-8℃Reagent 11EA-20℃Reagent 24EA-20℃Reagent 32EA-20℃Reagent 42EA-20℃Reagent PreparationReagent 1: Before use, centrifuge the vial to bring the powder to the bottom. Add 8.4 mL of distilled water to dissolve. Aliquot and store unused portions at -20°C.Reagent 2: Before use, centrifuge each vial to bring the powder to the bottom. Add 0.6 mL of distilled water to each vial to dissolve. Aliquot and store unused portions at -20°C. Avoid repeated freeze-thaw cycles. Use within 3 days.Reagent 3: Before use, centrifuge each vial to bring the powder to the bottom. Add 0.6 mL of distilled water to each vial to dissolve thoroughly. Can be aliquoted and frozen. Avoid repeated freeze-thaw cycles.Reagent 4: Before use, centrifuge each vial to bring the powder to the bottom. Add 0.6 mL of distilled water to each vial to dissolve thoroughly. Can be aliquoted and frozen. Avoid repeated freeze-thaw cycles.Required Materials and Equipment (Not Provided)UV spectrophotometer, 1 mL quartz cuvette (1 cm light path), refrigerated benchtop centrifuge, constant temperature incubator, pipettes, mortar and pestle, ice, and distilled water.Sample Preparation1.Tissue Samples: Weigh approximately 0.1 g of tissue. Add 1 mL of Extraction Buffer and homogenize on ice. Centrifuge the homogenate at 12,000 rpm (approx. 13,000-15,000 g), 4°C for 10 min. Collect the supernatant and keep it on ice for assay.Note: For larger samples, use an Extraction Buffer volume (mL) to tissue mass (g) ratio between 5:1 and 10:1.2.Bacteria/Cell Samples: Collect cells by centrifugation and discard the supernatant. Add 1 mL of Extraction Buffer per 5 million cells/bacteria. Disrupt the cells/bacteria by sonication on ice (20% power or 200W, pulse 3s on/10s off, repeat 30 times). Centrifuge the lysate at 12,000 rpm, 4°C for 10 min. Collect the supernatant and keep it on ice for assay.Note: For larger samples, use an Extraction Buffer volume (mL) to cell count (10⁴ cells) ratio between 1:1000 and 1:5000.Assay Procedure:1.Preheat the UV spectrophotometer for at least 30 minutes. Set the wavelength to 340 nm. Zero the instrument with distilled water.2.Pre-warm all reagents at 37°C for 5-15 minutes.3.Optional Master Mix: A Master Mix can be prepared just before use by combining Extraction Buffer, Reagent 1, Reagent 2, Reagent 3, and Reagent 4 in a 400:160:40:20:20 ratio (e.g., for one assay: 400µL + 160µL + 40µL + 20µL + 20µL = 640µL). Pipette 640 µL of this Master Mix per cuvette. Prepare the Master Mix fresh for immediate use.4.Pipette into a 1 mL quartz cuvette (1 cm light path) in the following order:ReagentVolume (µL)Extraction Buffer400Reagent 1160Reagent 240Reagent 320Reagent 420Mix thoroughly and incubate at 37°C for 5 min.Sample60Mix thoroughly immediately after adding the sample. Record the initial absorbance (A₁) at 340 nm at 10 seconds. Record the absorbance again (A₂) after exactly 10 minutes. Calculate ΔA = A₁ - A₂.Notes & Troubleshooting:1.If ΔA is close to zero, consider extending the reaction time (e.g., to 20 min) to read A₂. Use the new reaction time (T) in the calculation. Alternatively, increase the sample volume V₁ (e.g., to 100 µL, decrease Extraction Buffer accordingly) and use the new V₁ and T in the calculation.2.If the initial absorbance A₁ is too high (e.g., >2, common in deeply pigmented plant samples), reduce the sample volume V₁ and use the new V₁ in the calculation. Alternatively, add a small amount of activated charcoal to the sample supernatant, mix, let stand for 5 min, centrifuge at 12,000 rpm, 4°C for 10 min, and use the clarified supernatant for assay.3.If ΔA is greater than 0.6, reduce the reaction time (e.g., to 5 min) and use the new time (T) in the calculation.4.If the decrease is not linear, read the absorbance every 10 seconds and select a linear segment for calculating ΔA. Use the corresponding time interval (T) for the calculation.ACK Activity Calculation:General Parameters:ε (NADH molar extinction coefficient) = 6.22 × 10³ L/mol/cmd (Cuvette light path) = 1 cmV (Total extraction volume) = 1 mLV₁ (Sample volume in reaction) = 0.06 mL (60 µL)V₂ (Total reaction volume) = 0.0007 L (700 µL)T (Reaction time) = 10 min500 (Cell/Bacteria count in ten-thousands: 500 × 10⁴ = 5 million)W (Sample mass, g)Cpr (Sample protein concentration, mg/mL)1. Based on Sample Protein Concentration:Definition: One unit of activity is defined as the amount of enzyme that consumes 1 nmol of NADH per minute per mg of protein.Calculation:ACK Activity (nmol/min/mg prot) = [ΔA ÷ (ε × d) × V₂ × 10⁹] ÷ (Cpr × V₁ / V) ÷ TSimplified Formula: ACK (nmol/min/mg prot) = 187.6 × ΔA ÷ Cpr2. Based on Sample Fresh Weight:Definition: One unit of activity is defined as the amount of enzyme that consumes 1 nmol of NADH per minute per gram of fresh tissue.Calculation:ACK Activity (nmol/min/g fresh weight) = [ΔA ÷ (ε × d) × V₂ × 10⁹] ÷ (W × V₁ / V) ÷ TSimplified Formula: ACK (nmol/min/g fresh weight) = 187.6 × ΔA ÷ W3. Based on Bacterial/Cell Density:Definition: One unit of activity is defined as the amount of enzyme that consumes 1 nmol of NADH per minute per 10⁴ cells/bacteria.Calculation (for 5 million cells in 1 ml extract):ACK Activity (nmol/min/10⁴ cell) = [ΔA ÷ (ε × d) × V₂ × 10⁹] ÷ (500 × V₁ / V) ÷ TSimplified Formula: ACK (nmol/min/10⁴ cell) = 0.38 × ΔAPrecautionsBefore formal assay, it is essential to perform a pilot test with 2-3 samples expected to have significant differences in activity... Read More | 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 | Inquire | Inquire | 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 |