| 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 | Product Characteristics Effect Diluents, Animal-free are effective buffers free of any animal components. They can be used for the dilution of serum, plasma, blood, stool or urine samples, as well as the dilution of primary and secondary antibodies. Effect Diluents, Animal-free efficiently minimize Product Characteristics Effect Diluents, Animal-free are effective buffers free of any animal components. They can be used for the dilution of serum, plasma, blood, stool or urine samples, as well as the dilution of primary and secondary antibodies. Effect Diluents, Animal-free efficiently minimize matrix effects, cross-reactions and unspecific binding in immunoassays like ELISA, Western blotting, Immunohistochemistry, protein arrays and immuno-PCR.The Effect Diluents, Animal-free are used alternatively to the standard sample or antibody dilution buffers: In ELISA for the dilution of specimen and detection antibodies. In Western Blotting for the dilution of primary and secondary antibodies. In Protein arrays for the dilution of specimen and detection antibodies. In immuno-PCR as a washing buffer.Three versions of the diluent are offered: Low, Medium and High for optimal discrimination between specific and unspecific reaction and for minimizing strong interference effects e.g., by RF (rheumatoid factors), HAMAs (human-a-mouse Abs) or by endogenous components that bind and mask the analyte.Composition & Properties The Effect Diluents, Animal free contain no animal components and are free of phosphates.Working Procedure 1.Mix thoroughly prior to use. 2.Dilution recommendations a.Dilute antibodies according to the instruction of the antibody b.Dilution of the specimen is recommended at 1:2 or higherTips & TricksEffect Diluents must not be considered as blocking buffers. Recommended blocking buffers are: Synthetic Blocking Buffer, ELISA (cat. no. S494401), Synthetic Blocking Buffer, Blotting (cat. no. S494457) and WellChampion (cat. no. W494467) for plate blocking and stabilization (preparation of pre-coated plates). Complex sample matrices, such as serum and plasma, may contain interfering factors that affect the ability of the assay to accurately quantify the target analyte. Strong interferences are often caused by RFs and HAMAs. This matrix effect can cause high background in the negative control or false negatives in the sample measurement. To reduce this effect the samples can be diluted in the Effect Diluents, Animalfree.Handling & Storage Store solution 2-8°C or -15 to -30°C (tolerates freezing and thawing cycles)... Read More | Product content:E665636Component50 TStorageE665636ABuffer P115 mLRTE665636BBuffer P215 mLRTE665636CBuffer E315 mLRTE665636DBuffer PS15 mLRTE665636EBuffer PW (concentrate)10 mLRTE665636FEndo-Free Buffer EB10 mLRTE665636GRNase A (10 mg/mL)150 µLRTE665636HEndo-Remover FMwith Collection Tubes50 Product content:E665636Component50 TStorageE665636ABuffer P115 mLRTE665636BBuffer P215 mLRTE665636CBuffer E315 mLRTE665636DBuffer PS15 mLRTE665636EBuffer PW (concentrate)10 mLRTE665636FEndo-Free Buffer EB10 mLRTE665636GRNase A (10 mg/mL)150 µLRTE665636HEndo-Remover FMwith Collection Tubes50 EARTE665636ISpin Columns DMwith Collection Tubes50 EART Product Introduction:Endotoxins are a common pollutant in plasmid extraction. Due to the high sensitivity of eukaryotic cells to endotoxins, the presence of endotoxins in plasmids can greatly reduce the transfection efficiency of eukaryotic cells. This reagent kit provides a simple, fast, and efficient new method for extracting endotoxin free plasmids. The extracted plasmids remove endotoxins to the maximum extent possible and can effectively remove contamination of genomic DNA, RNA, proteins, etc. The operation is simple and convenient. This reagent kit is suitable for extracting 1-5mL of bacterial solution. On the basis of alkaline lysis of cells, it efficiently and specifically binds plasmid DNA through a new silicon-based membrane. Each adsorption column can adsorb up to 40% µ The plasmid DNA of g is effectively removed using a special buffer system and endotoxin removal filter column, effectively removing impurities such as endotoxins and proteins. The plasmid obtained from this kit has high purity and stable quality, making it particularly suitable for cell transfection. It can also be used for downstream experiments such as DNA sequencing, PCR, PCR based mutations, in vitro transcription, transformed bacteria, and endonuclease digestion.Self prepared reagents: anhydrous ethanol, isopropanol.Preparation and important precautions before the experiment：1. All components can be stably stored for 1 year in a dry, room temperature (15-30 ℃) environment. The adsorption column can be stored for a longer time at 2-8 ℃. Buffer P1 with RNase A added can be stably stored for 6 months at 2-8 ℃. 2. Before the first use, add all RNase A solution to Buffer P1, mix well, and store at 2-8 ℃. Before use, let it sit at room temperature for a period of time. After returning to room temperature, use.3.Before the first use, anhydrous ethanol should be added to the Buffer PW according to the instructions on the reagent bottle label.4. Before use, please check if there is any crystallization or precipitation in Buffer P2 and Buffer E3. If there is any crystallization or precipitation, you can take a water bath at 37 ℃ for a few minutes to restore clarity.5. Be careful not to come into direct contact with Buffer P2 and Buffer E3, and immediately cover them tightly after use.6.The amount and purity of plasmid extraction are related to factors such as bacterial culture concentration, strain type, plasmid size, and plasmid copy number.Operation steps：1. Take 1-5 mL of overnight cultured bacterial solution and add it to a centrifuge tube (provided). Centrifuge at 13000 rpm (~16200 × g) for 30 seconds to collect bacteria, and try to discard all the supernatant as much as possible.2. Add 250 to the centrifuge tube containing bacterial sediment µ L Buffer P1 (please check if RNase A has been added first), mix thoroughly with a pipette or vortex oscillator, and suspend bacterial precipitation.Attention: If the bacterial blocks are not thoroughly mixed, it will affect the cracking effect, resulting in low extraction amount and purity.3. Add 250 to the centrifuge tube µ L Buffer P2, gently invert and mix 8-10 times, allowing the bacterial cells to fully lyse. Leave at room temperature for 3-5 minutes. At this point, the solution should become clear and viscous.Attention: Mix gently and do not shake vigorously to avoid interrupting genomic DNA and mixing genomic DNA fragments in the extracted plasmid. If the solution does not become clear, it indicates that the bacterial count may be too high and the lysis may not be complete. The bacterial count should be reduced.4. Add 250 to the centrifuge tube µ L Buffer E3, immediately invert and mix 8-10 times until white flocculent precipitates appear. Let it stand at room temperature for 5 minutes. Centrifuge at 13000 rpm for 5 minutes, extract the supernatant, and add it to a filter column (Endo Remove FM). Centrifuge at 13000 rpm for 1 minute to filter, and collect the filtrate in a centrifuge tube (self provided).Attention: After adding Buffer E3, it should be mixed evenly immediately to avoid local precipitation. 5. Add 225 to the filtrate µ Mix L isopropanol upside down.6. Column balance: Add 200 to the spin columns DM that have been loaded into the collection tube µ L Buffer PS, centrifuge at 13000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.7. Transfer the mixed solution of filtrate and isopropanol from step 5 to an equilibrium adsorption column (already loaded into a collection tube).8.13000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.Attention: The maximum volume of the adsorption column is 750 µ L. If the sample volume is greater than 750 µ L can be added in batches. 9. Add 750 to the adsorption column µ L Buffer PW (please check if anhydrous ethanol has been added first), centrifuge at 13000 rpm for 1 minute, and discard the waste liquid in the collection tube.10. Place the adsorption column back into the recovery manifold and centrifuge at 13000 rpm for 1 minute. Note: The purpose of this step is to remove residual ethanol from the adsorption column, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).11. Place the adsorption column in a new collection tube and add 50-100 to the middle of the adsorption membrane µ L Endo Free Buffer EB, let it stand at room temperature for 2-5 minutes, centrifuge at 13000 rpm for 2 minutes, and collect the plasmid solution into a centrifuge tube- Store the plasmid at 20 ℃.Note: 1) To increase the efficiency of plasmid recovery, the obtained solution can be added back to the adsorption column, left at room temperature for 2-5 minutes, centrifuged at 13000 rpm for 2 minutes, and collected into a centrifuge tube.2) When the plasmid copy number is low or>10 kb, preheating the Endo Free Buffer EB in a water bath at 65-70 ℃ can increase the extraction efficiency... Read More | Inquire | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export |