| Description | Phosphoenolpyruvate Carboxykinase (PEPCK, EC 4.1.1.32) is widely present in animals, plants, microorganisms, and cells. It catalyzes the conversion of oxaloacetate to phosphoenolpyruvate and is a key regulatory enzyme in the gluconeogenesis pathway.Assay PrinciplePEPCK catalyzes the conversion of Phosphoenolpyruvate Carboxykinase (PEPCK, EC 4.1.1.32) is widely present in animals, plants, microorganisms, and cells. It catalyzes the conversion of oxaloacetate to phosphoenolpyruvate and is a key regulatory enzyme in the gluconeogenesis pathway.Assay PrinciplePEPCK catalyzes the conversion of Oxaloacetate to Phosphoenolpyruvate and CO₂. Pyruvate Kinase and Lactate Dehydrogenase subsequently catalyze the sequential oxidation of NADH to NAD⁺. The rate of decrease in NADH absorbance at 340 nm is measured, which reflects PEPCK activity.Component100TStorageExtraction Buffer100 mL2-8℃Reagent 118 mL2-8℃Reagent 216.5 µL2-8℃Reagent 31EA-20℃Reagent 41EA-20℃Required Materials and Equipment (Not Provided)Spectrophotometer / Microplate reader, benchtop centrifuge, adjustable pipettes, micro quartz cuvette / 96-well plate, mortar and pestle, ice, and distilled water.Sample Preparation:1.Bacteria or Cultured Cells:Collect cells by centrifugation and discard the supernatant.Add Extraction Buffer at a ratio of 1 ml per 5-10 million cells (e.g., 1 ml for 5 million cells).Sonicate on ice (20% power or 200W, pulse 3s on/10s off, repeat 30 times).Centrifuge at 8000 g, 4°C for 10 min. Collect the supernatant and keep it on ice for assay.2.Tissues:Homogenize tissue on ice in Extraction Buffer at a ratio of 1:5-10 (w/v) (e.g., 0.1 g tissue in 1 ml buffer).Centrifuge at 8000 g, 4°C for 10 min. Collect the supernatant and keep it on ice for assay.3.Serum (or Plasma) Samples:Assay directly.Assay Procedure:1.Preheat the spectrophotometer or microplate reader for at least 30 minutes. Set the wavelength to 340 nm. Zero the instrument with distilled water.2.Preparation of Working Solution: Just before use, transfer and dissolve Reagent 2 and Reagent 3 into Reagent 1. Mix well. Aliquot and store any unused portions at -20°C. Avoid repeated freeze-thaw cycles.3.Preparation of Reagent 4: Just before use, dissolve the contents of the vial in 1 ml of distilled water. Mix well. Aliquot and store any unused portions at -20°C. Avoid repeated freeze-thaw cycles.4.Pre-warm the Working Solution and dissolved Reagent 4 at 37°C (for mammalian samples) or 25°C (for other species) for 5 minutes.5.In a micro quartz cuvette or a well of a 96-well plate, add:10 µl sample10 µl dissolved Reagent 4180 µl pre-warmed Working SolutionMix immediately and record the initial absorbance (A₁) at 340 nm. Record the absorbance again (A₂) after exactly 1 minute. Calculate ΔA = A₁ - A₂.Note: For this kit, if ΔA is greater than 0.1, dilute the sample with Extraction Buffer by an appropriate factor (account for this dilution factor 'n' in the calculations) so that ΔA is less than 0.1 to improve detection sensitivity.PEPCK Activity Calculation:1. Calculation for Micro Quartz Cuvette (d = 1.0 cm)General Parameters for Cuvette:Vₜₒₜₐₗ (Total reaction volume) = 0.0002 L (200 µL)ε (NADH molar extinction coefficient) = 6220 L/mol/cmd (Cuvette light path) = 1.0 cmVₛₐₘₚₗₑ (Sample volume in reaction) = 0.01 mL (10 µL)T (Reaction time) = 1 minVₛₐₘₚₗₑₜₒₜₐₗ (Total extract volume) = 1 mL (for tissues/cells)Cpr (Sample protein concentration, mg/mL)W (Sample mass, g)500 (Cell/Bacteria count in millions for example calculation: 5 million)a. For Serum (Plasma):Definition: One unit of activity is defined as the amount of enzyme that consumes 1 nmol of NADH per minute per ml of serum.Calculation:PEPCK Activity (nmol/min/ml) = [ΔA × Vₜₒₜₐₗ ÷ (ε × d) × 10⁹] ÷ Vₛₐₘₚₗₑ ÷ TSimplified Formula: PEPCK (nmol/min/ml) = 3215 × ΔAb. For Tissues, Bacteria, or Cells: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:PEPCK Activity (nmol/min/mg prot) = [ΔA × Vₜₒₜₐₗ ÷ (ε × d) × 10⁹] ÷ (Vₛₐₘₚₗₑ × Cpr) ÷ TSimplified Formula: PEPCK (nmol/min/mg prot) = 3215 × ΔA ÷ CprBased 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:PEPCK Activity (nmol/min/g fresh weight) = [ΔA × Vₜₒₜₐₗ ÷ (ε × d) × 10⁹] ÷ (W × Vₛₐₘₚₗₑ / Vₛₐₘₚₗₑₜₒₜₐₗ) ÷ TSimplified Formula: PEPCK (nmol/min/g fresh weight) = 3215 × ΔA ÷ WBased on Bacterial or 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.Calculation (example for 5 million cells in 1 ml extract):PEPCK Activity (nmol/min/10⁴ cell) = [ΔA × Vₜₒₜₐₗ ÷ (ε × d) × 10⁹] ÷ (500 × Vₛₐₘₚₗₑ / Vₛₐₘₚₗₑₜₒₜₐₗ) ÷ TSimplified Formula: PEPCK (nmol/min/10⁴ cell) = 6.43 × ΔA2. Calculation for 96-Well Plate (d = 0.5 cm)General Parameters for 96-Well Plate:(All parameters remain the same except for the light path 'd')d (96-well plate light path) = 0.5 cma. For Serum (Plasma):Simplified Formula: PEPCK (nmol/min/ml) = 6430 × ΔAb. For Tissues, Bacteria, or Cells:Based on Sample Protein Concentration:Simplified Formula: PEPCK (nmol/min/mg prot) = 6430 × ΔA ÷ CprBased on Sample Fresh Weight:Simplified Formula: PEPCK (nmol/min/g fresh weight) = 6430 × ΔA ÷ WBased on Bacterial or Cell Density:Simplified Formula: PEPCK (nmol/min/10⁴ cell) = 12.86 × ΔAPrecautionsBefore formal assay, it is essential to perform a pilot test with 2-3 samples expected to have significant differences in activity... Read More | Inquire | Product content: M665794Component125 TStorageM665794A2×miRNA qPCR Mixture (ROX)2×750 µL-20℃. Avoid freeze/thaw cycleM665794BReverse Primer, 10 µM60 µL-20℃. Avoid freeze/thaw cycleM665794CddH2O1.5 mL-20℃. Avoid freeze/thaw cycle Product Introduction:This kitProduct content: M665794Component125 TStorageM665794A2×miRNA qPCR Mixture (ROX)2×750 µL-20℃. Avoid freeze/thaw cycleM665794BReverse Primer, 10 µM60 µL-20℃. Avoid freeze/thaw cycleM665794CddH2O1.5 mL-20℃. Avoid freeze/thaw cycle Product Introduction:This kit uses the principle of SYBR Green I chimeric fluorescent dye method for miRNA fluorescence quantitative PCR detection. The kit includes 2 x miRNA qPCR Mixture and Reverse Primer required for detection. 2 x miRNA qPCR Mixture is a new generation pre mixed form of fluorescence quantitative PCR detection reagent specially developed for miRNA quantitative detection. The fluorescent dye SYBR Green I contained in it can bind to all double stranded DNA, making the product suitable for detecting different target sequences without the need to synthesize specific labeled probes. The GoldStar Taq DNA polymerase is a chemically modified and highly efficient thermal starter enzyme, coupled with a unique buffer system, which enhances reaction specificity, sensitivity, and enables accurate quantification of miRNA over a wider range. The 2x miRNA qPCR Mixture contains ROX dye and is suitable for fluorescence quantitative PCR instruments that require ROX as a calibration dye.Note: This kit must be used in conjunction with the miRNA cDNA first strand synthesis kit.Self prepared experimental materials: qPCR upstream primer.Forward Primer design principles:1. Follow the most common principles of primer design.2.Based on mature miRNA sequences, replacing U with T is the most basic and simplest design method.3.The Tm value of the downstream primer provided in the reagent kit is 63.6 ℃, and the Tm value of the upstream primer should be designed to be around 63.6 ℃ as much as possible.4. If the Tm value of the primer directly designed according to principle "2" is too low, several bases (preferably G or C bases) can be added to the 5 'end of the primer; One or several A bases can also be added at the 3 'end; Alternatively, both the 5 'and 3' ends can be modified simultaneously.5.If the Tm value of a primer designed directly according to principle "2" is too high, several bases can be removed from the 5 'or 3' end of the primer.Notes:1. Before using the reagent, please gently mix it upside down to avoid foaming, and use it after a brief centrifugation.2. The amount of miRNA first strand cDNA added should not exceed 10% of the volume of Real time PCR.3. For special detection systems, high content of cDNA templates can easily lead to non-specific amplification. Dilute cDNA appropriately (10 or 100 times dilution) based on the abundance of detected miRNAs.4. The 2x miRNA qPCR Mixture in this product contains SYBR Green I and ROX dyes. When storing this product or preparing PCR reaction solution, strong light exposure should be avoided.5. Avoid repeated freezing and thawing of this product. Repeated freezing and thawing may cause a decrease in product performance. This product can be stored at -20 ℃ for long-term storage. If frequent use is required in the short term, the 2xmiRNA qPCR Mixture can be stored at 2-8 ℃. However, the Reverse primer still needs to be stored at -20 ℃.Operation steps:1. Melt 2 x miRNA qPCR Mixture and Reverse Primer at room temperature (10 µ M). 2. When using, please gently mix the 2x miRNA qPCR Mixture upside down to avoid foaming, and use after brief centrifugation. If the reagent is not well mixed, its reaction performance will decrease.3. Place the reagent on ice and prepare the reaction system according to the following table: reagent volume final concentration 2×miRNA qPCR Mixture（ROX） 10 µl 1× Forward primer（10 µM） 0.4µl 0.2 µM Reverse primer（10 µM） 0.4µl 0.2 µM MiRNA first strand cDNA X µl — ddH2O up to 20 µl —4. The reaction program is set as follows:Attention!The pre denaturation reaction of this product must be completed at 95 ℃ for 10 minutes! Note: 1) The hot start enzyme used in this product must be activated under pre denaturation conditions of 95 ℃ and 10 minutes.2) The annealing temperature should be set at 60-64 ℃ as a reference range. When non-specific reactions occur, the annealing temperature can be increased... Read More | Products contentN665954Component24 T96 TStorageN665954ATPS V136 µL144 µL-20℃. Avoid freeze/thaw cycle.N665954B5×FA Reaction Buffer96 µL384 µL-20℃. Avoid freeze/thaw cycle.N665954CTS Buffer72 µL288 µL-20℃. Avoid freeze/thaw cycle.N665954D2× Products contentN665954Component24 T96 TStorageN665954ATPS V136 µL144 µL-20℃. Avoid freeze/thaw cycle.N665954B5×FA Reaction Buffer96 µL384 µL-20℃. Avoid freeze/thaw cycle.N665954CTS Buffer72 µL288 µL-20℃. Avoid freeze/thaw cycle.N665954D2× PCR Mix600 µL2×1.2 mL-20℃. Avoid freeze/thaw cycle. * This kit is suitable for human genomic DNA library construction, the starting template DNA input amount is 1 ng, our company also has 50 ng and 5 ng of human genomic DNA starting transposase method library construction kit, in order to get a higher quality library, different starting amount of DNA is recommended to use different kits. Products IntroductionThis kit is developed for Illumina's high-throughput sequencing platform and provides the enzyme premix system and reaction buffer for genomic DNA library construction, including all components except PCR primers. Compared with the traditional library construction kits, this kit adopts the new transposase method for library construction, which can complete DNA fragmentation, end repair and junction reaction in one simple enzymatic reaction, significantly reducing the amount of template, reducing the number of experimental steps, and shortening the time of library construction; it adopts the high-fidelity DNA polymerase for library enrichment, and the preference-free PCR amplification can expand the coverage area of the sequence, which can be used for efficient and effective sequencing. The use of high-fidelity DNA polymerase for library enrichment and preference-free PCR amplification broadens the coverage area of the sequence and enables efficient preparation of DNA libraries for Illumina's second-generation sequencing platform. The kit is suitable for use with 1 ng of starting template DNA, and all reagents in the kit have been subjected to stringent quality control and functional validation to maximize the stability and reproducibility of library construction.Product Features● DNA fragmentation and junction ligation in one step.● Ultra-fidelity amplification minimizes amplification preference.Provide your own instruments, kits and consumables1. Magnetic frame: DynaMagTM-2 is recommended.2. DNA purification and recovery kit: It is recommended to use Kangwei DNA purification and recovery kit by magnetic bead method.3. Library PCR primer kit: It is recommended to use Kangwei transposase method for second generation sequencing multi-sample primer kit.4. Anhydrous ethanol, deionized water (pH between 7.0 and 8.0).5. Reaction tubes: It is recommended to use low adsorption PCR tubes with 1.5 ml centrifuge tubes.Tip: It is recommended to use a high quality filter tip to prevent contamination of kits and library samples. Pre-experiment Preparation and Important Notes1. Avoid repeated freezing and thawing of reagents.2. PCR products are easily contaminated due to improper operation, resulting in inaccurate results. It is recommended to isolate the PCR reaction system preparation area from the PCR product purification area, and to use special pipettes to clean the experimental areas at regular intervals.3. Bead purification: the beads should be equilibrated to room temperature before use, all operations on the beads should be carried out at room temperature, 80% ethanol should be dispensed freshly, the beads should be rinsed and dried until the surface is free of liquid reflections and has a frosted appearance, insufficient drying of the beads will cause ethanol residue that will affect the subsequent experiments, and over-drying of the beads will affect the efficiency of DNA recovery.4. The kit is suitable for human genomic DNA library construction, if the DNA sample is a PCR product, it should be ensured that its length>.500 bp, since transposases do not work on DNA ends, it is recommended to extend the PCR product by 50-100 bp at each end of the PCR product to avoid low coverage of the ends for sequencing. Sample PreparationDNA purity requirement: A260/A280 = 1.8-2.0. Sample DNA: dissolved in ultrapure water.DNA quantification: Too much or too little DNA will affect the quality of the library. It is recommended to use Nano to test the purity of the genomic DNA and then use Qubit to test the concentration of the genome (do not use any absorbance-based assay for template quantification). Schematic diagram of DNA banking process procedureDNA fragmentation, junction reaction 1. Add the following reagents to a 200 µl PCR tube:2. Mix by gently blowing with a pipette and centrifuge briefly so that all components are collected at the bottom of the tube.3. Place the above PCR tubes in the PCR instrument with the hot cap on and program the reaction as follows:inactivation reactionAfter the DNA is fragmented, the enzyme is still in a high active state, so it should be removed from the PCR instrument immediately and terminated by adding the Reaction Termination Buffer, in order to prevent the DNA from being fragmented too much and resulting in smaller library fragments.1. Add 3 µl of TS Buffer to the PCR tube containing the fragmentation product.2. Mix by gently blowing with a pipette and centrifuge briefly so that all components are collected at the bottom of the tube.3. Incubate at room temperature for 5 min, or if the room temperature is too low, place the reaction on a PCR instrument at 25°C with the thermal cover closed.PCR amplification1. Add the following reagents to a 200 µl PCR tube.2. Mix by gently blowing with a pipette and centrifuge briefly so that all components are collected at the bottom of the tube. 3. Place the above PCR tubes in the PCR instrument with the thermal cap open, and the reaction program is as follows:Selective recovery of library DNA fragmentsIt is recommended to use CombiVision Magnetic Beads DNA Purification and Recovery Kit for selective recovery of DNA fragments. When different sizes of DNA fragments are required, the amount of magnetic beads used is different, please refer to the attached table for the specific amount of magnetic beads used.(If using other brands of magnetic beads, you need to figure out the optimal amount of magnetic beads by yourself).Note: Amplification products can also be fragment length sorted and purified using the Gum Recovery Kit. If there is no special requirement for library length distribution, amplification products can also be purified directly from DNA fragments without selective recovery of DNA fragments as described on page 4 of the manual.1. CMPure should be equilibrated at room temperature for 30 min after shaking and mixing before use.2. Transfer the PCR products to a 1.5 ml centrifuge tube, rehydrate to 100 µl, add several volumes of magnetic beads equilibrated to room temperature, vortex for 5 seconds, and let stand at room temperature for 5 minutes.3. Centrifuge briefly, place the tube on a magnetic rack to separate the beads from the supernatant until the solution is clear, and carefully aspirate the supernatant and transfer it to a new 1.5 ml centrifuge tube.Note: Do not discard the top clear.4. Add several volumes of magnetic beads to the supernatant, vortex and shake for 5 seconds, then let stand at room temperature for 5 minutes.5. Centrifuge briefly, place the tube on a magnetic rack to separate the beads from the supernatant until the solution is clear, carefully aspirate the supernatant and discard it, avoiding contact with the beads that have bound the target DNA.Note: Do not discard the beads.6. Continue to keep the centrifuge tube fixed on a magnetic rack and add 200 µl of freshly prepared 80% ethanol to the tube and allow to stand at room temperature for 30 seconds, carefully discarding the supernatant.Note: When adding ethanol, the liquid must not be blown directly onto the beads.7. Repeat step 6 once.8. Keep the centrifuge tube fixed on a magnetic rack and leave to dry at room temperature until the surface of the beads is slightly cracked, add 20 µl of ddH2O to solubilize.Note: Do not over-dry the beads as this may affect the elution efficiency.9. Remove the tube from the magnetic rack, vortex to completely resuspend the beads, and allow to stand at room temperature for 5 minutes. Centrifuge briefly, place the tube on the magnetic rack until the solution is clear, and transfer the supernatant solution to a new tube. Table: Suggested amount of magnetic beads for different segment selection recoveryLibrary DNA fragment purificationWe recommend the use of the Kangwei Century Magnetic Bead Method DNA Purification and Recovery Kit.1. CMPure should be equilibrated at room temperature for 30 min after shaking and mixing before use.2. 50 µl of magnetic beads equilibrated to room temperature were added to the PCR product, vortexed and shaken for 5 seconds, and then left to stand at room temperature for 5 minutes.3. Centrifuge briefly, place the tube on a magnetic rack to separate the beads from the supernatant solution until the solution is clear (approximately 3-5 minutes), carefully aspirate the supernatant and discard it, avoiding contact with the beads that have bound the target DNA. Note: Do not discard the beads.4. Continue to keep the centrifuge tube fixed on a magnetic rack and add 200 µl of freshly prepared 80% ethanol to the centrifuge tube and allow to stand at room temperature for 30 seconds, carefully discarding the supernatant.Note: When adding ethanol, the liquid must not be blown directly onto the beads.5. Repeat step 4.6. Keep the centrifuge tube fixed on a magnetic rack and leave to dry at room temperature until the surface of the beads is slightly cracked, add 25 µl of ddH2O to solubilize.Note: Do not over-dry the beads as this may affect the elution efficiency.7. Remove the tube from the magnetic rack, vortex to completely resuspend the beads, and allow to stand at room temperature for 5 minutes. Centrifuge briefly, place the tube on the magnetic rack until the solution is clear, and transfer the supernatant solution to a new tube. Library quality controlDetermination of library concentrationIn order to obtain high-quality sequencing results, accurate quantification of DNA libraries is required, and the first recommendation is to use Real-timePCR methods are used for absolute quantification of DNA libraries. Additionally, fluorescent dye methods such as the Qubit method or the fluorescent dye picogreen method can be used; do not use quantification methods based on absorbance measurements here. The following approximate formula can be used to convert the molar concentration of the DNA library.Library fragment distributionThe prepared DNA libraries can be detected by agarose gel electrophoresis or Agilent 2100 Bioanalyzer.Range of segment length distributions... Read More | Apoptosis refers to the cell autonomous and orderly death controlled by genes to maintain the stability of the internal environment. Apoptosis is different from cell necrosis. Apoptosis generally refers to a programmed cell death process that occurs during the development of body cells or under the Apoptosis refers to the cell autonomous and orderly death controlled by genes to maintain the stability of the internal environment. Apoptosis is different from cell necrosis. Apoptosis generally refers to a programmed cell death process that occurs during the development of body cells or under the action of some factors through the regulation of intracellular genes and their products. Cell necrosis is a cell death process that is caused by strong physical and chemical or biological factors to cause disordered changes in cells. The difference between apoptosis and necrosis lies in the characteristic morphological and biochemical changes, including the changes of cell membrane permeability and nuclear chromatin, the contraction of cytoplasm and the loss of membrane asymmetry. The oxazole yellow/pi membrane permeability apoptosis detection kit produced by our company is a dual fluorescence detection kit based on oxazole yellow and PI dyes. This kit is suitable for fluorescence microscopy, flow cytometry, fluorescence microplate reader and other fluorescence detection systems. Oxazole yellow is a non cell membrane penetrating cyanine monomer green fluorescent dye with high affinity for DNA. It basically has no fluorescence when it is not bound to DNA, but can emit bright green fluorescence after binding to DNA. When apoptosis occurs, the permeability of cell membrane changes. At this time, oxazole yellow can enter the cell and bind to DNA, emitting bright green fluorescence. Therefore, it is often used for the detection of apoptosis. It should be noted that oxazole yellow can also stain dead cells, so it needs to be double stained with PI that specifically fluorescently stains dead cells to effectively determine apoptosis. PI (propidium iodide) is a red fluorescent dye that can stain DNA. It is an analog of pyridine bromide that releases red fluorescence after embedding double stranded DNA. Although PI cannot pass through the membrane of living cells, it can cross the damaged cell membrane of dead cells to stain nuclei. Therefore, oxazole yellow combined with PI can be directly used for the detection of apoptosis. Apoptotic cells show green fluorescence, dead cells show both red and green fluorescence positive, and living cells have little or no fluorescence.Components: Components O598364-50T A. Oxazole yellow dye 50 µL B. Propidium Iodide (PI) 50 µLUsage (using flow cytometry as an example):1. Cell preparation(1) For adherent cells, after trypsin digestion, resuspend in culture medium and wash once with pre cooled PBS; The digestion time of trypsin should not be too long to prevent false positives. Note: Digest with trypsin and allow the cells to recover in the optimal cell culture conditions and medium for about 30 minutes, then stain.(2) For suspended cells, centrifuge at 1000 rpm for 5 minutes, discard the supernatant, and wash once with pre cooled PBS.2. Cell stainingSuspend cells in pre cooled PBS, with a recommended cell count of 106 cells/mL per sample. Add 1 µ L Oxazole Yellow and 1 µ L to 1 mL of the samplePI， Gently blow and mix well. Incubate on ice in the dark for 30 minutes. Note: We suggest adding the following two experimental controls:Blank tube: negative control group cells, without dye, used to regulate voltage.Single staining tube: Positive control group cells were treated with only two tubes, Oxazole yellow and PI, for regulating compensation.3. Flow detectionAfter incubation, the sample can be directly detected by flow cytometry, or centrifuged at 1000 rpm for 5 minutes, the supernatant can be aspirated, and the sample can be resuspended in 1 mL of pre cooled PBS for flow cytometry detection. Oxazole yellow can be excited by a 488 nm laser, and the detected fluorescence emission spectrum is around 530 ± 30 nm (FITC channel), while the PI channel emission spectrum is around 617 nm (PI or PE channel).Product parameters：Oxazole yellow dye:ex/em = 491 / 509 nm (bound DNA); Propidium iodine:ex/em = 535 / 617 nm (combined with DMatters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. fluorescent dyes have quenching problems. Please try to avoid light to slow down fluorescence quenching. 3. for your safety and health, please wear experimental clothes and disposable gloves.Scope of application：Membrane permeability apoptosis assay... 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