| Description | Pyruvate Kinase (PK, EC 2.7.1.40) is widely present in animals, plants, microorganisms, and cultured cells. It catalyzes the final step of glycolysis and is one of the key rate-limiting enzymes in glycolysis, as well as a crucial enzyme for ATP production. Therefore, determining PK activity is of Pyruvate Kinase (PK, EC 2.7.1.40) is widely present in animals, plants, microorganisms, and cultured cells. It catalyzes the final step of glycolysis and is one of the key rate-limiting enzymes in glycolysis, as well as a crucial enzyme for ATP production. Therefore, determining PK activity is of significant importance.Detection Principle: PK catalyzes the conversion of phosphoenolpyruvate and ADP to ATP and pyruvate. Lactate dehydrogenase (LDH) further catalyzes the reaction of NADH and pyruvate to produce lactate and NAD⁺. The change in NADH absorbance at 340 nm is measured to calculate the PK activity in the sample.Applicable Samples: Animal/plant tissues, cells, bacteria, serum (plasma)A1501205Component48T96TStorageA1501205AExtraction Buffer60 mL60 mL×22-8℃A1501205BAssay Buffer12 mL24 mL2-8℃A1501205CSubstrate Mix1EA1EA-20℃. Store in the dark.A1501205DLDH10.2 µL20.4 µL2-8℃Please check the quantity of each component before the experiment.An additional 10% of each component is provided beyond the specified volume for standard curve preparation or preliminary experiments.User-Provided Instruments and ReagentsTypeNameNotesInstrumentMicroplate ReaderCapable of measuring absorbance at 340 nm.Consumables96-well UV PlateUV-transparent plate.ReagentsPBS (pH 7.4) / Deionized WaterFor washing cells/bacteria / Reagent preparation.OthersHomogenizer (for tissue samples), incubator, ice bucket, low-temperature centrifuge, adjustable pipettes and tipsUsing a multichannel pipette for large-scale detection can improve efficiency.Experimental Procedure1. Reagent PreparationReagent NameReagent PreparationPrecautionsExtraction BufferReady-to-use; equilibrate to room temperature before use.Store at 4°C.Assay BufferReady-to-use; equilibrate to room temperature before use.Store at 4°C.Substrate Mix Working ReagentPrepare before use: For 48T: Add 10.2 mL Assay Buffer and 0.6 mL deionized water to the vial. For 96T: Add 20.4 mL Assay Buffer and 1.2 mL deionized water to the vial. Dissolve thoroughly.After preparation, aliquot and store at -20°C for up to 6 months. Avoid repeated freeze-thaw cycles. Before use, incubate at 25°C (for general species) or 37°C (for mammals) for 5 min.LDH Working ReagentPrepare before use: For 48T: Add 0.6 mL deionized water to the LDH vial. For 96T: Add 1.2 mL deionized water to the LDH vial. Mix thoroughly.Keep on ice after preparation. The diluted reagent can be stored at 4°C for 1 month.2. Sample PreparationNote: Fresh samples are recommended. If not used immediately, samples can be stored at -80°C for up to 1 month.2.1 Animal/Plant Tissues: Weigh approximately 0.1 g of tissue, add 1 mL of Extraction Buffer, and homogenize on ice. Centrifuge at 8000 g, 4°C for 10 minutes. Collect the supernatant and keep on ice for detection.2.2 Cells/Bacteria: Collect 5×10⁶ cells or bacteria into a centrifuge tube. Wash with cold PBS, centrifuge, and discard the supernatant. Add 1 mL of Extraction Buffer. Disrupt by ultrasonic homogenization on ice (power 20% or 200 W, ultrasonicate for 3 s, interval 7 s, repeat 30 times). Centrifuge at 8000 g, 4°C for 10 minutes. Collect the supernatant and keep on ice for detection.2.3 Serum (Plasma) and other liquid samples: Detect directly.3. Assay Steps3.1 Microplate Reader Preparation: Preheat for at least 30 minutes. Set the wavelength to 340 nm.3.2 Assay System Setup: In a 96-well UV plate, add sequentially: 10 µL of sample, 10 µL of LDH Working Reagent, and 180 µL of Substrate Mix Working Reagent. Mix rapidly immediately after addition.3.3 Absorbance Measurement: Immediately after mixing, measure the absorbance at 340 nm at 20 seconds (A1) and then at 2 minutes and 20 seconds (A2). Calculate ΔA = A1 - A2.4. Result Calculation4.1 Data ProcessingCalculate ΔA = A1 - A2.4.2 Sample PK Activity Calculation(1) Based on sample mass:Unit Definition: One unit of enzyme activity is defined as the consumption of 1 nmol NADH per minute per gram of tissue in the reaction system.Formula:PK (U/g) = [ΔA×Vtotal reaction÷ (ε × d) × 10⁹] ÷ (Vsample ÷ Vtotal extract×W) ÷ T = 3215 × ΔA ÷ W(2) Based on cell/bacterial count:Unit Definition: One unit of enzyme activity is defined as the consumption of 1 nmol NADH per minute per 10⁴ bacteria or cells in the reaction system.Formula:PK (U/10⁴) = [ΔA × Vtotal reaction ÷ (ε × d) × 10⁹] ÷ (Vsample ÷ Vtotal extract; × 500) ÷ T = 3215 × ΔA ÷ 500 = 6.431 × ΔA(3) Based on liquid volume:Unit Definition: One unit of enzyme activity is defined as the consumption of 1 nmol NADH per minute per mL of serum (plasma) in the reaction system.Formula:PK (U/mL) = [ΔA × Vtotal reaction; ÷ (ε × d) × 10⁹] ÷ Vsample ÷ T = 3215 × ΔA(4) Based on protein concentration:Unit Definition: One unit of enzyme activity is defined as the consumption of 1 nmol NADH per minute per mg of protein in the reaction system.Formula:PK (U/mg prot) = [ΔA × Vtotal reaction; ÷ (ε × d) × 10⁹] ÷ (Cpr × Vsample ) ÷ T = 3215 × ΔA ÷ CprParameter Description:Vtotal reaction; : Total reaction volume, 2 × 10⁻⁴ Lε: Molar extinction coefficient of NADH, 6.22 × 10³ L/mol/cmd: Light path of the 96-well plate, 0.5 cm10⁹: Conversion factor (1 mol = 1 × 10⁹ nmol)Vsample : Volume of sample added, 0.01 mLVtotal extract; : Volume of Extraction Buffer added, 1 mLT: Reaction time, 2 minCpr: Sample protein concentration, mg/mLW: Sample mass, g500: Cell or bacterial count (5 × 10⁶), converted to units of 1Precautions1. It is recommended to perform preliminary experiments using 2-3 samples expected to have significant differences before formal testing.2. This kit is compatible with spectrophotometer detection. Adjust the preparation volume of detection reagents proportionally according to the spectrophotometer's requirements.3. For tissue and cell samples, results can be normalized by measuring the protein concentration. Aladdin BCA Protein Quantification Kit (B665595) or Ready-to-Use BCA Protein Quantification Kit (R1491648) are recommended.4. Biochemical reagents are generally irritating and biologically toxic. For your safety and health, please implement appropriate biosafety precautions throughout the experiment. Wear personal protective equipment such as lab coats, masks, gloves, and hair caps. Perform experiments in a fume hood or biosafety cabinet.5. This product is for scientific research use only. Not intended for clinical diagnosis.Frequently Asked QuestionsQ: What should I do if the sample ΔA is too high or too low?A: If the sample ΔA is > 1.0, the PK activity in the sample is too high. Dilute the sample appropriately with Extraction Buffer or reduce the amount of sample used for extraction, and then re-assay. If the sample ΔA is < 0.005, extend the reaction time to 5 or 10 minutes, or appropriately increase the sample amount, and then re-assay.Q: Will testing multiple samples simultaneously affect the results?A: Appropriately extending the time by 3-5 minutes for this assay will not affect the results. When testing multiple samples, it is recommended to use a multi-channel pipette for operation... Read More | DescriptionThe 1 µm Coupling Kit makes conducting immunoprecipitation and biomolecule separation easier and more flexible. The Kit contains AnteoBind™activated 1 µm magnetic particles that give you increased antibody binding capacity and functionality, while the included blocking DescriptionThe 1 µm Coupling Kit makes conducting immunoprecipitation and biomolecule separation easier and more flexible. The Kit contains AnteoBind™activated 1 µm magnetic particles that give you increased antibody binding capacity and functionality, while the included blocking buffer decreases background noise. Reduce reagent preparation time; remove traditional surface preparation steps such as EDC and replace these steps with the 1 µm pre-activated magnetic particles provided. This Kit reduces aggregation and gives you the freedom and ability to develop multifunctional particles for diverse applications, including dual labelling.Binding Capacity and Dispersity:Binding Capacity:> 20 µg IgG/mgMonodispersity:> 90% (by light microscopy determination)Particle based immunoassays, bioseparations and immunoprecipitation... Read More | Store at -20°C. Please refer to protocols | 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 |