| Description | Chloroplast 3-phosphoglycerate kinase (PGK) is a key enzyme in the Calvin cycle. Detection Principle: Chloroplast 3-phosphoglycerate kinase catalyzes the reaction of 3-phosphoglyceric acid and ATP to produce 1,3-bisphosphoglyceric acid. The latter, under the action of glyceraldehyde-3-phosphate Chloroplast 3-phosphoglycerate kinase (PGK) is a key enzyme in the Calvin cycle. Detection Principle: Chloroplast 3-phosphoglycerate kinase catalyzes the reaction of 3-phosphoglyceric acid and ATP to produce 1,3-bisphosphoglyceric acid. The latter, under the action of glyceraldehyde-3-phosphate dehydrogenase and NADH, produces glyceraldehyde-3-phosphate and NAD⁺. The enzyme activity of 3-phosphoglycerate kinase is determined by measuring the decrease in NADH.Component96TStorageExtraction Buffer 1100 mL2-8℃Extraction Buffer 2100 mL2-8℃Reagent 11EA-20℃. Store in the dark.Reagent 23EA2-8℃Reagent 31EA-20℃Reagent 435 mL2-8℃Reagent 51EA-20℃Reagent Preparation:Reagent 1 (Powder, 1 vial):Before opening, ensure the powder is at the bottom (can be flicked manually).Add 1.1 mL of distilled water to dissolve. Use after preparation.The prepared solution can be stored for the duration of the kit's validity period.Reagent 2 (Powder, 3 vials):Before use, centrifuge at 8000 g, 4°C for 2 minutes to collect the powder at the bottom.Add 0.4 mL of distilled water per vial to dissolve. Use after preparation.Unused dissolved reagent can be aliquoted and stored at -20°C. Avoid repeated freeze-thaw cycles. Use within 3 days.Reagent 3 (Powder, 1 vial):Before use, centrifuge at 8000 g, 4°C for 2 minutes to collect the powder at the bottom.Add 1.1 mL of distilled water to dissolve. Use after preparation.The prepared solution can be stored for the duration of the kit's validity period.Reagent 5 (Powder, 1 vial):Before use, centrifuge at 8000 g, 4°C for 2 minutes to collect the powder at the bottom.Add 1.1 mL of distilled water to dissolve. Use after preparation.The prepared solution can be stored for the duration of the kit's validity period.User-Prepared Instruments and MaterialsMortar (Homogenizer), Ice box (Ice maker), Benchtop centrifuge, Adjustable micropipettes, Water bath (Oven, Incubator, Metal bath), 96-well plate, Centrifuge tubes, Microplate reader, Vortex mixer/shaker, Distilled water (Deionized water or Ultrapure water are acceptable).Experimental ProcedureIt is recommended to first perform a preliminary test using 1-3 samples with expected significant differences (e.g., different types or groups) to familiarize yourself with the procedure and to determine or adjust sample concentrations based on the preliminary results, preventing unnecessary waste of samples or reagents.1. Sample Extraction (Chloroplast Isolation)Weigh approximately 0.1 g of plant tissue sample. Add 1 mL of Extraction Buffer 1 and homogenize rapidly in an ice bath. Centrifuge at 1,600 rpm, 4°C for 5 minutes. Discard the pellet. Take the supernatant and centrifuge again at 5,000 rpm, 4°C for 15 minutes. Discard the supernatant and keep the pellet. Add 1 mL of Extraction Buffer 2 to the pellet. Vortex vigorously for 15 seconds. Place on ice (or in a refrigerator) and incubate at 4°C for 15 minutes. Centrifuge at 13,000 rpm, 4°C for 5 minutes. Collect the supernatant for assaying the chloroplast 3-phosphoglycerate kinase (PGK) enzyme activity.Important: The entire chloroplast extraction process must be maintained at 4°C.Note: If increasing the sample amount, maintain a tissue mass (g) to Extraction Buffer volume (mL) ratio between 1:5 and 1:10.2. Assay Steps2.1 Preheat the microplate reader for 30 minutes. Set the wavelength to 340 nm and the temperature to 25°C.2.2 Thaw all reagents to room temperature (25°C).2.3 Add reagents sequentially to a 96-well plate:ReagentTest Well (µL)Sample20Reagent 110Reagent 210Reagent 310Reagent 4140Mix well and incubate at room temperature (25°C) for 10 minutes.Reagent 510Mix gently. Under room temperature (25°C) conditions, read the absorbance at 340 nm at 30 seconds (A₁) and then again after 10 minutes (A₂). Calculate ΔA = A₁ - A₂.注：Notes:(1) If ΔA is close to zero, the reaction time can be appropriately extended to 20 minutes before reading A₂. If the reaction time is changed, the new time (T) must be substituted into the calculation formula. Alternatively, the sample volume can be increased (e.g., to 40 µL, with a corresponding decrease in Reagent 4 volume); the new sample volume (V₁) must then be substituted into the calculation formula.(2) If the decrease trend is unstable, read the absorbance every 20 seconds and select a linearly decreasing time period for calculation. The corresponding A values for this period should be used to calculate ΔA and substituted into the formula.(3) If the initial absorbance A₁ is too high (e.g., >2, as in dark green plant leaves with high pigment content), consider appropriately reducing the sample volume; the new sample volume (V₁) must be substituted into the calculation formula. Alternatively, add a small amount of activated carbon to the sample, mix, let stand for 5 minutes, then centrifuge at 12,000 rpm, 4°C for 10 minutes, and use the supernatant for assay.(4) If ΔA is greater than 0.5, reduce the reaction time (e.g., to 5 minutes) or reduce the sample volume (e.g., to 10 µL). The changed reaction time (T) and/or sample volume (V₁) must be substituted into the calculation formula.3. Calculation of Results3.1 Based on Sample MassUnit Definition: One unit of enzyme activity is defined as the amount that consumes 1 nmol of NADH per minute per gram of tissue.Derived Formula: chl PGK (nmol/min/g fresh weight) = [ΔA ÷ (ε × d) × V₂ × 10⁹] ÷ (W × V₁ ÷ V) ÷ TSimplified Formula: chl PGK (nmol/min/g fresh weight) = 321.6 × ΔA ÷ W3.2 Based on Sample Protein ConcentrationUnit Definition: One unit of enzyme activity is defined as the amount that oxidizes 1 nmol of NADH per minute per mg of tissue protein.Derived Formula: chl PGK (nmol/min/mg prot) = [ΔA ÷ (ε × d) × V₂ × 10⁹] ÷ (V₁ × Cpr) ÷ TSimplified Formula: chl PGK (nmol/min/mg prot) = 321.6 × ΔA ÷ CprParameter Definitions:ε: Molar extinction coefficient of NADH (6.22 × 10³ L/mol/cm)d: Light path length for the 96-well plate (0.5 cm)V: Volume of Extraction Buffer added to the pellet (1 mL)V₁: Volume of sample added to the reaction (0.02 mL)V₂: Total volume of the reaction system (0.2 mL = 2.0 × 10⁻⁴ L)T: Reaction time (10 minutes)W: Sample weight (g)Cpr: Sample protein concentration (mg/mL); Aladdin's BCA Protein Quantification Kit (B665595) or Ready-to-Use BCA Protein Quantification Kit (R1491648) is recommended.Precautions It is strongly recommended to first perform a preliminary test using 1-3 samples with expected significant differences (e.g., different types or groups) to familiarize yourself with the procedure. Based on the preliminary results, determine or adjust sample concentrations to prevent unnecessary waste of samples or reagents... Read More | Alanine Aminotransferase (ALT), also known as serum glutamic-pyruvic transaminase (SGPT), is a pyridoxal-phosphate-dependent enzyme that catalyzes the reversible transfer of an amino group from alanine to α-ketoglutarate, generating pyruvate and glutamate. ALT is found primarily in liver and Alanine Aminotransferase (ALT), also known as serum glutamic-pyruvic transaminase (SGPT), is a pyridoxal-phosphate-dependent enzyme that catalyzes the reversible transfer of an amino group from alanine to α-ketoglutarate, generating pyruvate and glutamate. ALT is found primarily in liver and serum, but occurs in other tissues as well. Hepatocellular injury often results in an increase of serum ALT levels and serum ALT levels can be used as a marker for liver injury.ALT Activity Assay kit has been used to determine the activity of alanine aminotransferase (ALT) in serum samples... Read More | Lipid peroxidation is the degradation of lipids that occurs as a result of oxidative damage and is a useful marker for oxidative stress. Polyunsaturated lipids are susceptible to an oxidative attack, typically by reactive oxygen species, resulting in a well-defined chain reaction with the productionLipid peroxidation is the degradation of lipids that occurs as a result of oxidative damage and is a useful marker for oxidative stress. Polyunsaturated lipids are susceptible to an oxidative attack, typically by reactive oxygen species, resulting in a well-defined chain reaction with the production of end products such as malondialdehyde (MDA). Lipid peroxidation may contribute to the pathology of many diseases including atherosclerosis, diabetes, and Alzheimer′s.Lipid peroxidation (MDA) assay kit has been used to determine the levels of malondialdehyde (MDA).Suitability: Suitable for the measurement of malondialdehyde (MDA) in a variety of samples including tissue, cells and plasmaPrinciple: In this kit, lipid peroxidation is determined by the reaction of MDA with thiobarbituric acid (TBA) to form a colorimetric (532 nm)/fluorometric (λex= 532/λem= 553 nm) product, proportional to the MDA present... Read More | Products contentN665968Component96 TStorageN665968Adex N501-N508 Primers for Illumina 8×12 µL-20℃. Avoid freeze/thaw cycle.N665968BIndex N701-N712 Primers for Illumina 12×8 µL-20℃. Avoid freeze/thaw cycle. Products IntroductionThis kit is a companion kit for the Products contentN665968Component96 TStorageN665968Adex N501-N508 Primers for Illumina 8×12 µL-20℃. Avoid freeze/thaw cycle.N665968BIndex N701-N712 Primers for Illumina 12×8 µL-20℃. Avoid freeze/thaw cycle. Products IntroductionThis kit is a companion kit for the transposase-based second-generation sequencing Rapid DNA Library Construction Kit, designed for Illumina platform library construction, which contains 8 primers at the N5 end and 12 primers at the N7 end, which can be used to prepare 96 different bipartite Index libraries. All reagents provided in the kit have been subjected to stringent quality control and functional validation to maximize the stability and reproducibility of library construction. The prepared libraries can be sequenced on Illumina platforms such as HiSeq X-10/4000/2500/2000 and MiSeq. Provide your own instruments, reagents 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. DNA building kit: It is recommended to use the Kangwei Century transposase method second-generation sequencing rapid DNA building kit.4. Anhydrous ethanol.5. Reaction tubes: It is recommended to use low adsorption PCR tubes and 1.5 ml centrifuge tubes; tips: It is recommended to use high-quality filtration tips to prevent contamination of reagent kits and library samples. Pre-experiment Preparation and Important NotesPlease centrifuge briefly before opening the cap so that the liquid collects at the bottom of the tube to avoid cross-contamination between different primers.For the use of the CombiVision Second Generation Sequencing Multisample Primer Kit, please follow the CombiVision Second Generation Sequencing Rapid DNA Library Kit protocol.Index N501-N508 Primers for IlluminaIndex N701-N712 Primers for Illumina... Read More | Cell viability and cytotoxicity assays are usually used for drug screening and compound cytotoxicity testing. The CCK-8 kit uses highly water-soluble tetrazolium salt ( called WST-8 ) to produce water-soluble WST-8 for cell proliferation and cytotoxicity assays. Unlike MTT, WST-8 and WST-8 have no Cell viability and cytotoxicity assays are usually used for drug screening and compound cytotoxicity testing. The CCK-8 kit uses highly water-soluble tetrazolium salt ( called WST-8 ) to produce water-soluble WST-8 for cell proliferation and cytotoxicity assays. Unlike MTT, WST-8 and WST-8 have no cytotoxicity in cell culture medium, so multiple downstream experiments can be performed using the same detection plate. CCK-8 method is a convenient colorimetric method for the determination of cell viability. It does not need the solubilization process and only needs the least steps to provide the results. The CCK-8 method can be used for the determination of 96-well microplates and high-throughput screening of 384-well microplates. Advantage：At present, the commercially available liquid CCK-8 kits generally have defects such as harsh storage conditions ( -4C or -20 ), unstable use in different pH ranges, and easy deterioration ( discoloration or precipitation ). The solid instant CCK-8 kit adopts a new formula and Swiss process, which overcomes these shortcomings of the liquid CCK-8 kit. It can be stored at room temperature for a long time ( > 3 years ), ready to use, stable in a wide pH range, and the experimental results are more reliable. Compared with the liquid CCK-8 kit, the solid-soluble CCK-8 kit has higher sensitivity and the biological response time is shortened by half.Application scope:It can be used for drug screening, cell proliferation assay, cytotoxicity assay, tumor drug sensitivity test and activity detection of biological factors. Operating instructions:This reagent kit can be used for drug screening, cell proliferation assay, cytotoxicity assay, tumor drug sensitivity assay, and activity detection of biological factors.1. Carefully and slowly tear along the gap in the packaging bag;2. Pour all the powder in the bag into a clean container containing 10mL of ultrapure water, shake continuously for 1 minute, and use it when the solid is completely dissolved;3. Unused reagents must be stored at low temperatures below 4 ℃.Equipment required for testing:Enzyme reader 96 well plate with 450-490 nm filter;Carbon dioxide incubator;96 well plate, sterilized transparent plate for cell detection;Multi channel pipette (8 or 12 channels: 10-100 µ l);Blood cell counter or cell counter.Cell viability testing:1. Inoculate cell suspension (100 µ l/well) into a 96 well plate and pre culture the plate in a carbon dioxide incubator for 24 hours (37 ℃, 5% CO2);2. Add 10 µ l of CCK-8 solution to each well (be careful not to generate bubbles in the well as it may affect the reading of OD value);3. Incubate the culture plate in the incubator for 1-4 hours;4. Measure the absorbance at 450 nm using an enzyme-linked immunosorbent assay (ELISA) reader;5. If the OD value is not determined temporarily, 10 µ l of 0.1M HCI solution or 1% w/v SDS solution can be added to each well, and the culture plate can be covered and stored in the dark at room temperature. Within 24 hours of measurement, the absorbance will not change.Cell proliferation toxicity testing:1. Inoculate cell suspension (100 µ l/well) into a 96 well plate and pre culture the plate in an incubator for 24 hours (37 ℃, 5% CO2);2. Add 10ul of different concentrations of the substance to be tested to the culture plate;3. Incubate the culture plate in the incubator for an appropriate period of time (e.g. 6, 12, 24, or 48 hours);4. Add 10 µ l of CCK-8 solution to each well (be careful not to generate bubbles in the well as they may affect the reading of the OD value);5. Incubate the culture plate in the incubator for 1-4 hours;6. Measure the absorbance at 450nm using an enzyme-linked immunosorbent assay (ELISA) reader;7. If the OD value is not determined temporarily, 10 µ l of 0.1M HCI solution or 1% w/v SDS solution can be added to each well, and the culture plate can be covered and stored in the dark at room temperature. Within 24 hours of measurement, the absorbance will not change.Calculation method for cell survival rate/inhibition rate:Cell survival rate=[As Ab)/(Ac Ab)] x 100%Inhibition rate=[(Ac As)/(Ac Ab)] x 100%As: absorbance of experimental wells (including cells, culture medium, CCK-8 solution, and drug solution);Ac: absorbance of control wells (including cells, culture medium, CCK-8 solution, without drugs);Ab: Blank well absorbance (including culture medium and CCK-8 solution, excluding cells and drugs).Points for attention： 1.Unused reagents must be stored at low temperature below 4 °C, and stored in the dark at-20 °C for two years after unpacking, so as to avoid repeated thawing ; 2.The culture time of CCK-8 is generally 1-4 hours, but the naked eye can be taken out to observe the color degree in about 30 minutes. According to the cell type, the conditions need to be explored. The best reaction time of CCK-8 is based on the best time of specific color development.3. It is recommended to do a few holes to explore the number of inoculated cells and the culture time after adding CCK-8 reagent ; 3.The WST-8 in this kit will react with reducing agents ( such as some antioxidants ) to interfere with the detection. Before the cell proliferation-toxicity test, the background OD can be checked to confirm whether there is a reducing agent in the substance to be tested. If the effect of reducing agent needs to be removed, the fresh medium can be replaced before adding CCK-8 ( remove the medium, wash the cells twice with the medium, and then add the new medium ) ; 4.Phenol red in the medium does not affect the experimental results, and the absorbance of phenol red can be eliminated by deducting the absorbance of the background in the blank hole during calculation, so it will not affect the detection. 5.It is recommended to use a multi-channel pipette to reduce the difference between parallel holes. When adding CCK-8 reagent, it is recommended to add it obliquely to the wall of the culture plate, not to insert it under the liquid surface of the medium, which is easy to produce bubbles and interfere with OD determination. 6.If the drug contains metal, it has an effect on the color of CCK-8. The final concentration of 1mM lead chloride, ferric chloride and copper sulfate will inhibit the color reaction of 5 %, 15 % and 90 %, and reduce the sensitivity. If the final concentration is 10mM, the color reaction will be 100 % inhibited ; 7.When using a 96-well plate for detection, if the cell culture time is long, attention should be paid to the evaporation problem. On the one hand, because a circle around the 96-well plate is the easiest to evaporate, the method of discarding the surrounding circle can be adopted, and the same amount of PBS, water or culture medium can be added. On the other hand, the 96-well plate can be placed near the water source in the incubator to alleviate evaporation ; 8.When using standard 96-well plates, the minimum inoculation amount of adherent cells is at least 1,000 cells / well ( 100µl medium ). The sensitivity of detecting white blood cells is relatively low, so it is recommended that the inoculation amount should not be less than 2,500 cells / well ( 100 µl medium ). If you want to use a 24-well plate or a 6-well plate experiment, first calculate the corresponding inoculation amount per well, and add the CCK-8 solution according to 10 % of the total volume of the medium per well ; 9.Cell culture time varies according to the type and number of cells ( per well ), usually the color of white blood cells is weak, requiring a longer culture time ( 4 hours ) and a large number of cells ( ~ 105 cells / well ) ; 10.CCK-8 reagent is very low toxic to cells. The continuous reaction between it and dehydrogenase in living cells makes the color of the solution deepen and the OD value increase. The following methods can terminate the CCK-8 reaction ( 96-well plate ) : a ) After the color reaction, the culture plate was placed in a refrigerator at 4 ° C ; b ) 10µL 0.1MHCL solution was added to each well ; c ) 10 µL 1 % ( w / v ) SDS ( sodium dodecyl sulfate ) solution was added to each well. After the reaction stopped, the OD value should be measured within 24 hours. 11.To determine the specific number of cells, it is recommended to do the standard curve at the same time... Read More |