| Description | IntroductionCreatine Kinase (CK) is primarily found in tissues such as the heart, muscle, and brain. It reversibly catalyzes the transphosphorylation reaction between creatine and ATP, playing a vital role in energy transfer, muscle contraction, and ATP regeneration. It is a crucial clinical IntroductionCreatine Kinase (CK) is primarily found in tissues such as the heart, muscle, and brain. It reversibly catalyzes the transphosphorylation reaction between creatine and ATP, playing a vital role in energy transfer, muscle contraction, and ATP regeneration. It is a crucial clinical indicator for diagnosing heart and brain diseases.Assay PrincipleCK catalyzes the conversion of Phosphocreatine and ADP to Creatine and ATP. Hexokinase then catalyzes the reaction of ATP with Glucose to form Glucose-6-Phosphate (G6P). Subsequently, Glucose-6-Phosphate Dehydrogenase (G6PDH) catalyzes the oxidation of G6P with NADP⁺ to generate NADPH, leading to an increase in absorbance at 340 nm.Component50TStorageExtraction Buffer60 mL2-8℃Reagent 11EA2-8℃. Store in the dark.Reagent 215 mL2-8℃Reagent 1: Powder in one bottle. Store at 4°C protected from light. Dissolve in 15 mL distilled water before use.Working Solution: Prepare immediately before use by mixing the dissolved Reagent 1 and Reagent 2 at a 1:1 ratio. Incubate the Working Solution at 37°C for 2 minutes prior to use.Required Materials and Equipment (Not Provided)Balance, refrigerated centrifuge, constant temperature water bath, UV spectrophotometer, 1 ml quartz cuvette, and distilled water.Crude Enzyme Extraction:Tissue Samples: Homogenize the tissue on ice in Extraction Buffer at a ratio of 1:5-10 (w/v) (e.g., weigh ~0.1g tissue, add 1 mL Extraction Buffer). Centrifuge the homogenate at 10,000 g, 4°C for 15 min. Collect the supernatant and keep it on ice for assay.Serum Samples: Assay directly.Assay Procedure:Preheat the UV spectrophotometer for at least 30 minutes. Set the wavelength to 340 nm. Zero the instrument with distilled water.In a 1 ml quartz cuvette, add:200 µl sample300 µl distilled water500 µl pre-warmed (37°C) Working SolutionMix thoroughly and immediately record the initial absorbance (A₁) at 340 nm. Record the absorbance again (A₂) after exactly 1 minute at 37°C. Calculate ΔA = A₂ - A₁.CK Enzyme Activity Calculation:General Parameters:ε (NADPH molar extinction coefficient) = 6220 L/mol/cmd (Cuvette light path) = 1.0 cmVₜₒₜₐₗ (Total reaction volume) = 1.0 mL (1000 µL)Vₛₐₘₚₗₑ (Sample volume in reaction) = 0.2 mL (200 µL)T (Reaction time) = 1 minCpr (Sample protein concentration, mg/mL)W (Sample mass, g)Vₛₐₘₚₗₑₜₒₜₐₗ (Total extract volume) = Assumed 1 mL for tissue calculations1. Based on Tissue Protein Content:Definition: One unit of activity is defined as the amount of enzyme that generates 1 nmol of NADPH per minute per mg of protein at 37°C, pH 7.0.Calculation:CK Activity (nmol/min/mg prot) = [ΔA / (ε × d)] × Vₜₒₜₐₗ ÷ (Vₛₐₘₚₗₑ × Cpr) ÷ TSimplified Formula: CK (nmol/min/mg prot) = 804 × ΔA ÷ Cpr2. Based on Tissue Sample Mass:Definition: One unit of activity is defined as the amount of enzyme that generates 1 nmol of NADPH per minute per gram of fresh tissue at 37°C, pH 7.0.Calculation:CK Activity (nmol/min/g fresh weight) = [ΔA / (ε × d)] × Vₜₒₜₐₗ ÷ (Vₛₐₘₚₗₑ / Vₛₐₘₚₗₑₜₒₜₐₗ × W) ÷ TSimplified Formula: CK (nmol/min/g fresh weight) = 804 × ΔA ÷ W3. Based on Serum:Definition: One unit of activity is defined as the amount of enzyme that generates 1 nmol of NADPH per minute per liter of serum at 37°C, pH 7.0.Calculation:CK Activity (nmol/min/L) = [ΔA / (ε × d)] × Vₜₒₜₐₗ ÷ Vₛₐₘₚₗₑ ÷ TSimplified Formula: CK (nmol/min/L) = 804 × ΔANotesBefore the formal assay, it is essential to perform a pilot test with 2-3 samples expected to have significant differences in activity.The prepared Working Solution is stable at 4°C for 7 days. However, it is recommended to use it as soon as possible after preparation.CK in serum is unstable. Determine the activity as soon as possible after sample collection. It can be stored protected from light at 4°C for up to 24 hours.Sample protein content needs to be determined separately. A BCA Protein Assay Kit can be used for this purpose.If the absorbance value (ΔA) is greater than 0.5, dilute the sample appropriately with Extraction Buffer and account for the dilution factor (D) in the calculation formulas (e.g., 804 × ΔA × D ÷ Cpr)... Read More | Bacterial protein extraction reagents use mild non-ionic detergents and are suitable for extracting recombinant proteins expressed in Escherichia coli and insect cells. During the extraction process, there is no need for ultrasonic fragmentation, effectively avoiding contamination of exogenous Bacterial protein extraction reagents use mild non-ionic detergents and are suitable for extracting recombinant proteins expressed in Escherichia coli and insect cells. During the extraction process, there is no need for ultrasonic fragmentation, effectively avoiding contamination of exogenous proteins. This product can be applied to extract soluble proteins from bacterial lysates. The bacterial protein extraction kit adds a mixture of lysozyme, DNase I, and protease inhibitors to the extraction reagent, which can improve the efficiency of protein extraction and reduce the viscosity caused by DNA, effectively avoiding protein degradation. The extracted protein maintains biological activity and can be subjected to downstream operations such as IP, Western blot, and protein purification. Component B665764 100 preps Bacterial Protein Extraction Reagent 100 ml Protease Inhibitor Cocktail (100x) 1 ml Lysozyme （50 mg/ml） 200µl DNaseⅠ（1,000 U/ml） 100µl Notes:1. This product is suitable for extracting proteins from fresh or frozen bacterial and insect cells.2. This product uses Tris buffer system. Please use the same buffer system for protein purification after extraction.3. The protein lysis solution obtained from this product can be used for protein quantification using BCA or Bradford method.4. For special strains, if the extraction effect is not ideal, the sample can be frozen before protein extraction.5. Depending on the specific situation, protease inhibitors, salts, chelating agents, reducing agents, etc. can be added to this product.Operation steps: ● Insect cell protein extraction1. Collect cells by low-speed centrifugation. Add 10 to every 1 ml of Bacterial Protein Extraction Agent µ The Protein Inhibitor Cocktail is 1 x working fluid.2. Weigh the wet weight of the cells and add 1 x working solution at a rate of 10 ml/g.3. After resuspension, incubate on ice for 20 minutes (the ice storage time should be adjusted according to different cell types).Centrifuge at 4.15000 × g for 15 minutes to isolate soluble proteins. ● Extraction of soluble bacterial proteins 1. Centrifuge for 10 minutes at a rate of 5000 × g and collect the bacterial cells.2. Optional steps: Add 1 ml of Bacterial Protein Extraction Reagent every 1 ml µ DNase I (1000 U/ml), 2 µ Lysozyme (50 mg/ml) and 10 µ Protein Inhibitor Cocktail, vortex oscillation and mixing. 3. Add 20 ml of Bacterial Protein Extraction Reagent to each gram of bacterial precipitate, and add the extraction solution to the bacterial precipitate. Vortex thoroughly or use a pipette to blow up and down until the bacterial precipitate is completely resuspended.4. After resuspension, incubate at room temperature for 10-15 minutes (the storage time should be adjusted according to different cell types). 5. Centrifuge at 15000 × g for 5 minutes.6. Transfer the supernatant to a new centrifuge tube (the supernatant is soluble protein) for protein quantification and downstream experiments.Note: If the target protein exists in the form of inclusion bodies, inclusion body protein solution can be used for dissolution or expression conditions can be optimized to increase the expression of soluble proteins.Frequently asked questions: Problem Possible reasons Resolvent The target protein is insoluble The target protein is expressed as an inclusion body Optimize expression conditions or add Lysozyme and DNase I to protein extraction reagents using inclusion body protein solution After adding Lysozyme, the target protein has not been extracted yet Temperature too low Restore the reagent to room temperature After adding Lysozyme, the target protein has not been extracted yet Lysozyme Decreased or inactivated activity Add more Lysozymes or replace with new enzymes Extract has high viscosity DNase I Decreased or inactivated activity Add more DNase I or replace with a new DNase I to increase the final concentration of magnesium ions to 2 mM After protein extraction, most of the proteins still exist in the precipitate Excessive protein content Add Lysozyme and DNase I The protein extraction reagent has sediment precipitation Temperature too low Restore the protein extraction reagent to room temperature... Read More | Calcein AM /PI Double Staining Kitis utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stains viable and dead cells, respectively(Fig. 1). Calcein-AM, an acetoxymethyl ester of calcein, is highly Calcein AM /PI Double Staining Kitis utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stains viable and dead cells, respectively(Fig. 1). Calcein-AM, an acetoxymethyl ester of calcein, is highly lipophilic and cell membrane permeable. Though Calcein-AM itself is not a fluorescent molecule, the calcein generated from Calcein-AM by esterase in a viable cell emits a strong green fluorescence (excitationat 490 nm, emission at515 nm). Therefore, Calcein-AM only stains viable cells. On the other hand, PI, a nuclei staining dye, cannot pass through a viable cell membrane. It reaches the nucleus by passing through disordered areas of dead cell membrane, and intercalates with the DNA double helix of the cell to emit red fluorescence (excitation: 535 nm,emmision: 617 nm). Since both calcein and PI-DNA can be excited with 490 nm, simultaneous monitoring of viable and dead cells is possible with a fluorescence microscope. With 545 nm excitation, only dead cells can be observed (Fig. 1). Since optimal staining conditions differ from cell line to cell line, we recommend that a suitable concentration of PI and Calcein-AM be individually determined. Please note that PI is suspected to be highly carcinogenic;careful handling is required.Required Equipment and Materials:Microscope with 490 nm excitation filter and 530 nm emission filter；CO2incubator；10 µl and 200 µl adjustable pipettes, PBSSolution A (Calcein-AM)；Solution B (PI) Storage Condition: -20oC ；Shipping Condition: blue ice.Application:Assay Procedure1)Add 2.5 µl Solution A and 12.5 µl Solution B to 5 ml PBS to prepare assay solution.*2)Wash the cell with PBS several times to remove residual esterase activity.3)Add 100uLof assay solution to200uL105~106CELLSsolution and incubate the mixture at 37oC for 15 min.4)Detect fluorescence using a fluorescence mircoscope with 490 nm excitationfor simultaneous monitoring of viable and dead cells.With 545 nm excitation, only dead cells can be observed.*The following steps may be necessary tooptimizethe suitable concentration of each reagent:1)Prepare dead cells by 10 min incubation in 0.1% saponin or 0.1-0.5% digitonin or by 30 min incubation in 70% ethanol.2)Stain dead cells with 0.1-10 µM PI solution to find a PI concentration that stains the nucleus only, not the cytosol.3)Stain dead cells with 0.1-10 µM Calcein-AM solution to find a Calcein-AM concentration that does not stain the cytosol. Then stainviable cells with that Calcein-AM solution to check whether the viable cell can be stained... Read More | DescriptionIt contains a set of seven different homogeneous palladium catalysts, useful for rapid screening of catalysis conditions. It is in sampler format with individual components packaged for multiple experiments and mini scale-up. The cost of the kit is less than the total cost of individual DescriptionIt contains a set of seven different homogeneous palladium catalysts, useful for rapid screening of catalysis conditions. It is in sampler format with individual components packaged for multiple experiments and mini scale-up. The cost of the kit is less than the total cost of individual components.Catalysis Screening Kits... Read More | Q665720 Component 200T Storage Q665720A Buffer L2 25 mL RT Q665720B Buffer N3 80 mL RT Q665720C Buffer PB 35 mL RT Q665720D Buffer PW (concentrate) 25 mL RT Q665720E Buffer EB 30 mL RT Q665720F RNase A (10 mg/mL) 800 渭L RT Q665720G Spin Columns DM with Collection Tubes 200 EA RTProduct Q665720 Component 200T Storage Q665720A Buffer L2 25 mL RT Q665720B Buffer N3 80 mL RT Q665720C Buffer PB 35 mL RT Q665720D Buffer PW (concentrate) 25 mL RT Q665720E Buffer EB 30 mL RT Q665720F RNase A (10 mg/mL) 800 渭L RT Q665720G Spin Columns DM with Collection Tubes 200 EA RTProduct IntroductionThe biggest feature of this kit: simple and fast, high extraction volume. The whole extraction process does not take more than 10 minutes, without centrifugation to collect bacteria and resuspend the bacterium, directly add the unique super lysate Buffer L2 to the cultured bacterial solution, followed by neutralization, centrifugation and passing through the column, and the extracted plasmid can be as high as 30 µg, and maximize the removal of proteins, genomes and other impurities. The extracted plasmid DNA can be directly used for bacterial transformation, digestion, PCR, in vitro transcription, sequencing and other downstream experiments.Self-contained reagent: anhydrous ethanol.Pre-experiment Preparation and Important Notes1. The kit can be stored in a dry, room temperature (15-30°C) environment for 1 year. For longer storage, the centrifuge columns can be placed at 2-8°C.2. Before the first use, add all of the RNase A solution to Buffer N3, mix well, and store at 2-8°C.3. Anhydrous ethanol should be added to Buffer PW before the first use according to the instructions on the reagent bottle label.4. If there is any precipitation in Buffer L2 before use, please put it in a 37℃ water bath and keep mixing until the solution becomes clear before use.Operation steps1. Take 600 µl of bacterial culture into a 1.5 ml centrifuge tube (supplied).2. Add 100 µl of Buffer L2 to the above centrifuge tube and gently turn the solution up and down 8 times; the solution should change from turbid to a clear purple color, indicating complete lysis. The cleavage time should not exceed 2 minutes.3. Add 350 µl of Buffer N3 to the above centrifuge tube (please check that RNaseA has been added first) and immediately mix well by turning up and down about 8-10 times, at which point the solution should turn completely yellow and a yellow precipitate should form. centrifuge at 13,000 rpm for 2-3 minutes.4. Slowly pour the supernatant obtained in step 3 into the prepared adsorption columns (Spin Columns DM with Collection Tubes) to avoid sedimentation into the columns.5. Centrifuge at 13,000 rpm for 15 seconds, pour off the waste liquid in the collection tube, and put the adsorption column back into the collection tube.6. Add 150 µl Buffer PB to the adsorption column and centrifuge at 13,000 rpm for 15 seconds.7. Add 400 µl Buffer PW to the adsorption column (please check that anhydrous ethanol has been added first) and centrifuge at 13,000 rpm for 1 minute.8. Place the adsorbent column in a new centrifuge tube (self-provided), add 30-100 µl Buffer EB to the middle part of the adsorbent membrane, centrifuge at 13,000 rpm for 1 min, collect the plasmid DNA, and store at -20°C for long term storage.When the amount of extracted bacterial liquid is >600µl, the following procedure can be used:1. This kit can extract up to 3ml of bacterial solution, if the amount of extracted bacterial solution is more than 600µl, it is necessary to centrifuge the bacterial solution exceeding 600µl at 13,000rpm for 30 seconds (to collect the bacterial body), discard the supernatant and then add 600µl of bacterial solution, and then resuspend the bacterial body at the bottom of the tube thoroughly and then proceed to the following operation.2. Add 100µl Buffer L2 to the above centrifuge tube, gently invert the solution up and down 10 times, if the solution is not clarified, need to continue to invert the mixing until the solution becomes a clear purple color, the lysis time should not be more than 2 minutes. (If the solution is still turbid, the amount of bacteria is too large, and the amount of bacteria should be reduced appropriately.)3. Add 350 µl of Buffer N3 to the above centrifuge tube (please check that RNaseA has been added first) and immediately mix well by turning up and down until the purple solution turns completely yellow and a yellow precipitate is formed before proceeding to the next step. centrifuge at 13,000 rpm for 5 minutes.4. Transfer the supernatant to a new centrifuge tube, add 200 µl of isopropanol, mix up and down several times, mix well and transfer to the adsorbent column (Spin Columns DM with Collection Tubes), due to the amount of solution is too large, this time, it is necessary to centrifuge the column in two separate times, centrifugation at 13,000 rpm for 15 seconds, pour off the waste liquid in the collection tube, and put the adsorbent column back to the The adsorbent column should be placed back into the collection tube.5. Add 150 µl Buffer PB to the adsorption column and centrifuge at 13,000 rpm for 15 seconds.6. Add 400 µl Buffer PW to the adsorption column (please check that anhydrous ethanol has been added first) and centrifuge at 13,000 rpm for 1 minute.7. Place the adsorbent column in a new centrifuge tube (self-provided), add 50-200 µl Buffer EB to the middle part of the adsorbent membrane, leave it at room temperature for 2 min, centrifuge at 13,000 rpm for 1 min, collect the plasmid DNA, and store it at -20°C for a long time... Read More |