| Description | Glutathione is a tripeptide containing a γ-amide bond and a sulfhydryl group, composed of glutamate, cysteine, and glycine. It is widely found in animal and plant tissues and microorganisms. In living organisms, it helps maintain normal immune system function and has antioxidant and Glutathione is a tripeptide containing a γ-amide bond and a sulfhydryl group, composed of glutamate, cysteine, and glycine. It is widely found in animal and plant tissues and microorganisms. In living organisms, it helps maintain normal immune system function and has antioxidant and detoxifying effects. Glutathione exists in two forms: reduced (GSH) and oxidized (GSSG). GSSG, also known as glutathione disulfide, is formed by the oxidation of two glutathione molecules. GSSG can be reduced back to GSH by glutathione reductase; therefore, it exists primarily in the reduced form in organisms. The ratio of reduced to oxidized glutathione (GSH/GSSG) serves as a key dynamic indicator for assessing the cellular redox state. Detection Principle: Endogenous GSH in the sample is masked by 2-vinylpyridine. Under the catalysis of glutathione reductase (GR), GSSG is reduced to GSH. The generated GSH then reacts with 5,5'-Dithiobis-(2-nitrobenzoic acid) (DTNB) to produce yellow-colored 5-thio-2-nitrobenzoic acid (TNB), which has a characteristic absorption peak at 412 nm. The GSSG content is quantified by measuring the change in absorbance. Detection Range: 1-20 µM Sensitivity: 1 µM Applicable Samples: Animal/plant tissues, blood cells, cells, bacteria, serum (plasma).O1492795Component96TStorageO1492795AExtraction Buffer70 mL×22-8℃O1492795BInhibitor210 µL-20℃. Store in the dark.O1492795CAssay Buffer20 mL2-8℃O1492795DGR14 µL2-8℃. Store in the dark.O1492795EGR Cofactor2 EA-20℃. Store in the dark.O1492795FChromogen2 EA2-8℃. Store in the dark.O1492795GStandard1 EA2-8℃. Store in the dark.User-Provided Instruments and ReagentsTypeNameNotesInstrumentMicroplate ReaderCapable of measuring absorbance at 412 nm.Consumables96-well MicroplateStandard transparent plate.ReagentsPBS / Deionized WaterFor washing samples / Preparing reagents.OthersHomogenizer (for tissue samples), water bath, 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.Diluted Extraction BufferAdd 500 µL Extraction Buffer to 4.5 mL deionized water.Obtained by 10-fold dilution of Extraction Buffer.InhibitorReady-to-use; equilibrate to room temperature before use.Store at -20°C protected from light. Toxic and irritant; recommended to handle in a fume hood.Assay BufferReady-to-use; equilibrate to room temperature before use.Store at 4°C.GR DilutionBefore use, prepare by adding 1 µL GR to 20 µL deionized water per sample.Prepare freshly before use.GR Cofactor DilutionBefore use, add 1.5 mL deionized water to each vial; equilibrate to room temperature protected from light.After dissolution, store at -20°C protected from light for up to 1 month.Chromogen DilutionBefore use, add 1.5 mL deionized water to each vial; equilibrate to room temperature protected from light.After dissolution, store at 4°C protected from light for up to 1 month.GSSG StandardDissolve in 1 mL of Diluted Extraction Buffer.20 mM; After dissolution, aliquot and store at -20°C protected from light for up to 1 month.2. Standard PreparationTake 100 µL of the 20 mM GSSG standard and dilute with 900 µL Diluted Extraction Buffer to obtain a 2 mM GSSG standard solution.Take 10 µL of the 2 mM GSSG standard and dilute with 990 µL Diluted Extraction Buffer to obtain a 20 µM GSSG standard solution.Further dilute the standard as shown in the table below. A standard curve must be prepared for each experiment. Diluted standard solutions are unstable and must be used within 4 hours.Standard Working Solution20µM Standard (µL)Diluted Extraction Buffer (µL)Concentration (µM)110002028020163604012440608520804610902759513. Sample PreparationNote: Fresh samples are recommended. If not used immediately, samples can be stored at -80°C for up to 10 days. Because the Extraction Buffer contains a protein precipitant, the supernatant cannot be used for protein concentration determination. If protein content needs to be measured, prepare another identical sample using deionized water instead of Extraction Buffer.3.1 Animal/Plant Tissue Samples:Use fresh tissue samples whenever possible. Weigh 0.1 g of tissue, add 1 mL of pre-cooled Extraction Buffer, and homogenize quickly on ice (pre-cool the homogenizer on ice). Centrifuge the homogenate at 8000 g, 4°C for 10 min. Collect the supernatant and keep on ice for detection.3.2 Serum/Plasma Samples:Use fresh serum (plasma) whenever possible. Centrifuge the collected serum (plasma) at 600 g, 4°C for 10 min. Within 30 minutes, aspirate the supernatant into another tube. Add an equal volume of Extraction Buffer, mix, then centrifuge at 8000 g, 4°C for 10 min. Collect the supernatant and keep on ice for detection.3.3 Cell or Bacterial Samples:Use fresh cells (bacteria) whenever possible; avoid using frozen cells (bacteria). Collect 5×10⁶ cells (bacteria). Wash twice with 1 mL of pre-cooled PBS (resuspend in PBS, centrifuge at 600 g, 4°C for 10 min). Add 3 times the volume of Extraction Buffer relative to the cell (bacterial) pellet to resuspend the cells (bacteria). Disrupt by ultrasound 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 min. Collect the supernatant and keep on ice for detection.Note: Cells can also be extracted using a freeze-thaw method (not suitable for bacteria): Resuspend cells and subject to 2-3 rapid freeze-thaw cycles (freeze in liquid nitrogen, thaw in a 37°C water bath). Centrifuge at 8000 g, 4°C for 10 min. Collect the supernatant and keep on ice for detection.4. Assay Steps4.1 Microplate Reader Preparation: Preheat for at least 30 minutes, set wavelength to 412 nm.4.2 Assay System Setup (Step 1 - Pre-treatment): Perform the following operations in 1.5 mL EP tubes. This step must be done in EP tubes. Do not add Inhibitor directly to the 96-well plate as it may corrode the plate. Inhibitor is toxic and irritant; recommended to handle in a fume hood.ReagentBlank Tube (µL)Standard Tube (µL)Test Tube (µL)Sample003Deionized Water30027Standard0300Inhibitor1.51.51.54.3 Mix well and incubate at 37°C for 30 minutes. This becomes the "Mixture".4.4 Assay System Setup (Step 2 - Reaction): Perform the following operations in a 96-well plate.ReagentBlank Well (µL)Standard Well (µL)Test Well (µL)Mixture212121Assay Buffer140140140GR Dilution222GR Cofactor Dilution202020Chromogen Dilution2020204.5 Absorbance Measurement: Mix thoroughly after addition. Read the absorbance at 412 nm (A1), recorded as A1 blank, A1 standard, and A1 test. Then incubate at 37°C protected from light for 10 minutes. Quickly read the absorbance at 412 nm again (A2), recorded as A2 blank, A2 standard, and A2 test. 5. Result Calculation The following provides both the derived formula and the simplified calculation formula, which are completely equivalent. 5.1 Data Processing Calculate ΔA = A2 - A1 for each. Then calculate ΔΔA standard = ΔA standard - ΔA blank And ΔΔA test = ΔA test - ΔA blank 5.2 Standard Curve Plotting 5.2 Standard Curve Plotting Plot the standard curve with standard concentration as the y-axis and ΔΔA standard as the x-axis. Substitute ΔΔA test into the equation to obtain the y value (µM). 5.3 Sample GSSG Content Calculation (1) Based on sample mass: GSSG (nmol/g) = y × V standard ÷ V sample × V extract ÷ W × n = 10 × y ÷ W × n (2) Based on cell or bacterial count: GSSG (nmol/10⁴) = y × V standard ÷ V sample × V extract ÷ 500 × n = 0.02 × y × V extract × n (3) Based on liquid volume: GSSG (nmol/mL) = y × V standard ÷ V sample × 2 × n = 20 × y × n (4) Based on protein concentration: GSSG (nmol/mg prot) = y × V standard ÷ V sample ÷ Cpr × n = 10 × y ÷ Cpr × n Parameter Description: 1 µM = 1 nmol/mL; V standard : Volume of standard added, 30 µL; V sample : Volume of sample added, 3 µL; V extract : Volume of Extraction Buffer added, 1 mL (for cells/bacteria, use the actual volume used); W: Sample mass, g; n: Sample dilution factor; Cpr: Sample protein concentration, mg/mL; 500: Cell or bacterial count, in units of 10⁴; 2: Dilution factor for liquid samples (added equal volume of Extraction Buffer).6. Result PresentationTypical Standard Curve: y = 8.0042x + 0.212, R² = 0.9997Example-1: 0.1 g of rat liver tissue was processed and assayed according to the procedure using a 96-well plate. Measured: ΔA test = A2 test - A1 test = 0.386 - 0.120 = 0.266 ΔA blank = A2 blank - A1 blank = 0.132 - 0.097 = 0.035 ΔΔA test = ΔA test - ΔA blank = 0.266 - 0.035 = 0.231 Substituting ΔΔA test into the standard curve equation gives y = 2.061 µM. Calculated based on sample mass: GSSG (nmol/g) = y × V standard ÷ V sample × V extract ÷ W × n = 10 × y ÷ W × n = 206.1 nmol/g.Precautions1. It is recommended to perform preliminary experiments using 2-3 samples expected to have significant differences before formal testing.2. The samples extracted with this kit are suitable for the detection of oxidized glutathione (GSSG). Because the extraction buffer contains a protein precipitant, the supernatant cannot be used for protein concentration determination. If protein content needs to be measured, prepare another identical sample using deionized water instead of the extraction buffer. For protein concentration determination, Aladdin BCA Protein Quantification Kit (B665595) or Ready-to-Use BCA Protein Quantification Kit (R1491648) are recommended.3. This kit is compatible with spectrophotometer detection. Adjust the preparation volume of detection reagents proportionally according to the spectrophotometer's requirements.4. It is recommended to establish your own standard curve for improved accuracy. If not, you may refer to the typical standard curve formula provided in the results section for calculation.5. Biochemical reagents are generally irritating and biologically toxic. For your safety and health, please wear appropriate personal protective equipment (lab coat, mask, gloves, hair cap, etc.) throughout the experiment and perform experiments in a fume hood or biosafety cabinet.6. This product is for scientific research use only. Not intended for clinical diagnosis.Frequently Asked Questions Q: What should I do if the sample ΔA test is too high or too low? Frequently Asked Questions Q: What should I do if the sample ΔA test is too high or too low? A: If the sample ΔA test is greater than the ΔA standard of the 20 µM standard, the GSSG content in the sample is too high. Dilute the sample appropriately with deionized water (multiply by the dilution factor in the calculation). If the sample ΔA test is less than 0.005, increase the sample amount.Q: Can blood cell samples be detected?A: Yes, blood cell samples can be detected. Centrifuge the collected anticoagulated blood at 600 g, 4°C for 10 min. Discard the upper plasma and wash the pellet 2-3 times with 3 volumes of PBS (resuspend blood cells in PBS, centrifuge at 600 g, 4°C for 10 min). Add an equal volume of Extraction Buffer, mix, and let stand at 4°C for 10 min. Centrifuge at 8000 g, 4°C for 10 min. Collect the supernatant and keep on ice for detection... Read More | Inquire | 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 | DescriptionPhoto KitAlysis Starter Kit enables screening of 24 micro-scale simultaneous photocatalytic reactions with consistent and reproducible photon intensity. User guide is provided in the below hyperlink.Photo KitAlysis Operating InstructionsComponents:Photo KitAlysis LED ControllerBlue LED DescriptionPhoto KitAlysis Starter Kit enables screening of 24 micro-scale simultaneous photocatalytic reactions with consistent and reproducible photon intensity. User guide is provided in the below hyperlink.Photo KitAlysis Operating InstructionsComponents:Photo KitAlysis LED ControllerBlue LED Array (470 nm)Photo KitAlysis Reaction BlockTorque screwdriverSmall screwdriver to easily remove torqued screws after reaction is completeFeatures:Designed and tested by synthetic chemists.Controller provides repeatable milliamp selection for photon intensity0-30 mA variable LED output3 different LED options: blue (470 nm, included), green (527 nm, sold separately), and white (sold separately)Non-magnetic LED baseChemically resistant LED coverPTFE coated cablingDesigned to be used withPhoto KitAlysis High-Throughput Reaction Screening Kit(sold separately).Best when used withKitAlysis Benchtop Inertion Box(sold separately)... Read More | This reagent kit uses an adsorption column that can specifically bind to viral RNA and a unique buffer system, suitable for isolating viral RNA from cell-free body fluids such as serum, plasma, urine, cerebrospinal fluid, and cell culture supernatants. The viral RNA specifically binds to the siliconThis reagent kit uses an adsorption column that can specifically bind to viral RNA and a unique buffer system, suitable for isolating viral RNA from cell-free body fluids such as serum, plasma, urine, cerebrospinal fluid, and cell culture supernatants. The viral RNA specifically binds to the silicon substrate membrane, and pollutants flow through the membrane. Completely remove impurities such as proteins through two efficient washes, and then wash high-purity viral RNA with RNase free water or RNase Free Water provided by the reagent kit. The virus RNA extracted by this kit can be directly used for experiments such as RT-PCR, Real time RT-PCR, and Western blot analysis. R666005Component50 TStorageR666005ABuffer GL15 mLRTR666005BBuffer RW140 mLRTR666005CBuffer RW2（concentrate）11 mLRTR666005DProteinase K12.5 mgRTR666005EProteinase K Storage Buffer1.25 mLRTR666005FRNase-Free Water10 mLRTR666005GSpin Columns RS with Collection Tubes50 setsRTR666005HRNase-Free Centrifuge Tubes（1.5 mL）50 EART Self prepared reagent: anhydrous ethanol, 0.9% NaCl.Preparation and important precautions before the experiment1. Add 1.25 ml of Protein K Storage Buffer to Protein K to dissolve it and store at -20 ℃. The prepared Protein K should not be left at room temperature for a long time to avoid repeated freeze-thaw cycles, which may affect its activity.2. To prevent RNase pollution, attention should be paid to the following aspects:1) Use RNase free plastic products and gun heads to avoid cross contamination.2) Glassware should be dry baked at a high temperature of 180 ℃ for 4 hours before use, while plastic containers can be soaked in 0.5 M NaOH for 10 minutes, thoroughly rinsed with water, and then sterilized under high pressure.3) Prepare the solution using water without RNase.4) Operators should wear disposable masks and gloves, and change gloves frequently during the experiment.3. Serum or plasma should avoid repeated freeze-thaw cycles that may cause protein denaturation or precipitation, reduce viral titers, and thus affect the yield of extracted viral nucleic acids.4. Before the first use, anhydrous ethanol should be added to Buffer RW2 according to the instructions on the reagent bottle label.5. If buffer GL precipitates, it can be heated at 56 ℃ to dissolve and then placed at room temperature.6. All centrifugation steps should be carried out at room temperature unless otherwise specified, and all operation steps should be carried out quickly.Operation steps1. Take 200 at room temperature µ Add serum or plasma to a 1.5 ml centrifuge tube (self provided). Attention: Less than 200 µ 0.9% NaCl (provided by the customer) can be added to make up for it.2. Add 20 to the solution in the previous step µ Protein K, mix well.3. Add 200 µ L Buffer GL, vortex oscillation for 15 seconds. Note: Do not directly add Protein K to Buffer GL. 4. Incubate at 56 ℃ for 15 minutes, briefly centrifuge, and collect the solution on the tube wall to the bottom of the tube.5. Add 250 µ Anhydrous ethanol, vortex for 15 seconds, incubate at room temperature for 5 minutes, briefly centrifuge, and collect the solution from the tube wall to the bottom of the tube.6. Add all the solution obtained in step 5 to the Spin Columns RS that have been loaded into the collection tube. If it is not possible to add all the solution to the adsorption column at once, please transfer it in two batches, centrifuge at 12000 rpm (~13400 × g) for 1 minute, discard the waste liquid in the collection tube, and put the adsorption column back into the collection tube.7. Add 500 to the adsorption column µ Centrifuge at 12000 rpm for 1 minute, discard the waste liquid from the collection tube, and place the adsorption column back into the collection tube.8. Add 500 to the adsorption column µ Buffer RW2 (check if anhydrous ethanol is added before use), centrifuge at 12000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.9. Add 500 to the adsorption column µ Centrifuge anhydrous ethanol at 12000 rpm for 1 minute, discard the waste liquid from the collection tube, and place the adsorption column back into the collection tube. 10. Centrifuge at 12000 rpm for 3 minutes and discard the waste liquid from the collection tube. Place the adsorption column at room temperature for a few minutes to thoroughly air dry.Attention:1) The purpose of this step is to remove residual ethanol from the adsorption column, which will affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).2) Recommended steps: Place the adsorption column into a new 1.5 ml centrifuge tube (provided), open the tube cover, and incubate in a 56 ℃ oven for 3 minutes to thoroughly dry the membrane of the adsorption column.11. Place the adsorption column in a new RNase free centrifuge tube and add 20-50 to the middle of the adsorption column in the air µ Place RNase Free Water at room temperature for 5 minutes, centrifuge at 12000 rpm for 1 minute, collect RNA solution, and store RNA at -70 ℃ to prevent degradation.Attention:1) The volume of RNase Free Water should not be less than 20 µ l. Small volume affects the recovery rate.2) If you want to increase RNA production, you can use 20-50 µ Repeat step 11 for the new RNase Free Water.3) If you want to increase the RNA concentration, you can add the obtained solution back to the adsorption column and repeat step 11... Read More |