| Description | The hydroxyl radical (·OH) is the neutral form of the hydroxide ion (OH⁻) and possesses strong oxidizing capacity. Hydroxyl radicals act on biological molecules such as proteins, nucleic acids, and lipids within the body, damaging cellular structure and function, which can lead to The hydroxyl radical (·OH) is the neutral form of the hydroxide ion (OH⁻) and possesses strong oxidizing capacity. Hydroxyl radicals act on biological molecules such as proteins, nucleic acids, and lipids within the body, damaging cellular structure and function, which can lead to metabolic disorders and disease. The hydroxyl radical scavenging capacity is a key indicator of antioxidant ability and is widely used in research on antioxidant health products and pharmaceuticals.Detection Principle: H₂O₂/Fe²⁺ generates hydroxyl radicals via the Fenton reaction. Salicylic acid effectively captures these generated hydroxyl radicals and reacts with them to produce a purple compound, 2,3-dihydroxybenzoic acid. When a substance capable of scavenging hydroxyl radicals is added, it inhibits the formation of this purple product. Therefore, a darker color indicates a higher hydroxyl radical content, and vice versa. The change in absorbance at 520 nm is measured to calculate the sample's hydroxyl radical scavenging capacity.Applicable Samples: Animal and plant tissues, serum (plasma), cells, bacteria, cell culture supernatants, fruit juice, honey, urine, and other samples.P1501782Component48 T96 TStorageP1501782AFerrous Salt10 mL20 mL2-8℃. Store in the dark.P1501782BH₂O₂5 mL10 mL2-8℃. Store in the dark.P1501782CSalicylic Acid10 mL20 mL2-8℃. Store in the dark.Please check the quantities of all components before starting the experiment.An additional 10% of each component is provided beyond the specified volumes for standard curve preparation or preliminary experiments.User-Prepared Instruments and ReagentsTypeNameNotesInstrumentMicroplate ReaderCapable of measuring absorbance at 520 nm.Consumables96-well MicroplateStandard microplate.ReagentsPBS (pH7.4)For washing samples.OthersHomogenizer (for tissue samples), Incubator, Ice Box, Refrigerated Centrifuge, Adjustable Micropipettes and TipsUsing a multi-channel pipette can improve efficiency for large-scale assays.Experimental Procedure1. Reagent PreparationReagent NameReagent PreparationNotesFerrous SaltReady-to-use; Equilibrate to room temperature before use.Store at 4°C protected from light. Corrosive. Use appropriate personal protective equipment.H₂O₂Ready-to-use; Equilibrate to room temperature before use.Store at 4°C protected from light.Salicylic AcidReady-to-use; Equilibrate to room temperature before use.Store at 4°C protected from light. Irritating to skin and mucous membranes. Use appropriate personal protective equipment.2. Sample PreparationNote: Fresh samples are recommended. If not used immediately, samples can be stored at -80°C for one month. To compare the hydroxyl radical scavenging capacity of different samples, the dilution factor must be the same for the same batch of samples, and extracts or drugs should be prepared at the same concentration.2.1 Animal Tissue SamplesWeigh approximately 0.1 g of tissue, add 1 mL of deionized water, and homogenize in an ice bath. Centrifuge at 10,000 g, 4°C for 10 minutes. Collect the supernatant and keep it on ice for assay.2.2 Plant Tissue SamplesWeigh approximately 0.1 g of tissue, add 1 mL of deionized water and grind. Sonicate in an ice bath for 5 minutes (power 20% or 200W, pulse 3s on, 7s off, repeat 30 times). Centrifuge at 10,000 g, 4°C for 10 minutes. Collect the supernatant and keep it on ice for assay.2.3 Cells or BacteriaCollect 5×10⁶ cells or bacteria into a centrifuge tube. Wash with pre-cooled PBS, centrifuge, and discard the supernatant. Add 1 mL of deionized water. Sonicate in an ice bath for 5 minutes (power 20% or 200W, pulse 3s on, 7s off, repeat 30 times). Centrifuge at 10,000 g, 4°C for 10 minutes. Collect the supernatant and keep it on ice for assay.2.4 Serum (Plasma) and Other Protein-Rich or Turbid LiquidsTake 0.1 mL of sample, add 1 mL of deionized water and mix well. Centrifuge at 10,000 g, 4°C for 10 minutes. Collect the supernatant and keep it on ice for assay.2.5 Honey, Urine, and Other Clear Liquids with Low Protein ContentAssay directly.2.6 Extracts or DrugsCan be prepared to a specific concentration, e.g., 0.5 mg/mL.3. Assay Steps3.1 Microplate Reader Preparation: Preheat for at least 30 minutes. Set the wavelength to 520 nm.3.2 Assay System Setup: Perform the following operations in a 96-well plate. The Blank and Standard wells only need to be set up 1-2 times. Each test well requires a corresponding control well.ReagentBlank Well (µL)Standard Well (µL)Test Well (µL)Control Well (µL)Ferrous Salt40404040H₂O₂040400Deionized Water120804080Salicylic Acid40404040Sample0040403.3 Absorbance Measurement: Mix well, incubate at 37°C for 20 minutes. Read the absorbance at 520 nm, recorded as A blank, A standard, A test, and A control respectively.4. Calculation of ResultsBoth the derived formula and the simplified formula provided below are equivalent.4.1 Data ProcessingCalculate ΔA test = A test - A control Calculate ΔA standard = A standard - A blank 4.2 Calculation of Hydroxyl Radical Scavenging RateHydroxyl Radical Scavenging Rate D% = (ΔA standard - ΔA test ) / ΔA standard × 100%5. Representative ResultsExample: 0.1 g of nectarine pulp was taken and assayed according to the procedure using a 96-well plate.Measured: ΔA standard = A standard - A blank = 1.020 - 0.051 = 0.969ΔA test = A test - A control = 0.465 - 0.052 = 0.413Calculated Hydroxyl Radical Scavenging Rate D% = (0.969 - 0.413) / 0.969 × 100% = 57.38%Precautions1. Before formal testing, it is recommended to perform a preliminary test with 2-3 samples expected to have significant differences.2. For tissue samples, cell samples, etc., results can be normalized between samples by measuring protein concentration. Aladdin's BCA Protein Quantification Kit (B665595) or Ready-to-Use BCA Protein Quantification Kit (R1491648) is recommended.3. This kit is compatible with spectrophotometer detection. Adjust the reagent preparation volumes proportionally according to the spectrophotometer's requirements.4. Biochemical reagents are generally irritating and potentially biologically toxic. For your safety and health, implement appropriate biosafety precautions throughout the experiment, including wearing lab coats, masks, gloves, and head covers. Perform experiments in a fume hood or biosafety cabinet.5. This product is for research use only. Not for use in clinical diagnosis.Frequently Asked QuestionsQ: What should I do if the measured ΔA test for the sample is too high or too low?A: If ΔA test < 0.02, appropriately increase the sample volume and re-run the assay. If ΔA test > ΔA standard, further dilute the sample with deionized water or reduce the amount of sample used for extraction, and re-run the assay... Read More | Product Content D669986Component50 TStorageD669986ABuffer SA15 mLRTD669986B2×PCR MasterMix1 mL-20℃. Avoid freeze/thaw cycle.D669986CProteinase K12.5 mgRTD669986DProteinase K Storage Buffer1.25 mLRTProductsThis kit adopts a unique buffer system containing all the reagents for rapid Product Content D669986Component50 TStorageD669986ABuffer SA15 mLRTD669986B2×PCR MasterMix1 mL-20℃. Avoid freeze/thaw cycle.D669986CProteinase K12.5 mgRTD669986DProteinase K Storage Buffer1.25 mLRTProductsThis kit adopts a unique buffer system containing all the reagents for rapid preparation of genomic DNA and PCR amplification, and is suitable for one-step extraction of genomic DNA from various plant and animal tissues and bacteria and for PCR amplification. The whole extraction process does not require liquid nitrogen grinding, organic solvent extraction, anhydrous ethanol precipitation, and the quality of extracted DNA is stable. The 2×PCR MasterMix provided in this kit is a highly compatible PCR reagent that can amplify DNA samples efficiently and specifically, which includes DNA polymerase, dNTPs, MgCl2, reaction buffer, PCR reaction enhancer and so on. It is characterized by fast and easy, high sensitivity, high specificity, good stability, etc. It is especially suitable for high throughput screening.Pre-experiment Preparation and Important Notes1. Add the specified amount of Proteinase K Storage Buffer to Proteinase K to dissolve it and store it at -20℃. Do not leave the prepared Proteinase K at room temperature for a long time, and avoid repeated freezing and thawing to avoid affecting its activity.2. Repeated freezing and thawing of the samples should be avoided, as this will result in smaller DNA fragments and a decrease in the amount of extracted DNA.3. Before use, please check Buffer SA for crystallization or precipitation. If crystallization or precipitation occurs, please re-dissolve Buffer SA in a 56℃ water bath.4. The PCR MasterMix provided with this product is 2×, when using it, you need to add template and primer, and add RNase-Free Water to make up the volume, so that its concentration is 1× to carry out the reaction.Procedure1. Fetch:Plant material: take about 10 mg of sample in a centrifuge tube (provided); Animal material: take about 10 mg of sample in a centrifuge tube (provided);Bacteria: Take 200-800 µL of bacteria in good growth condition in a centrifuge tube (self-provided) and collect the bacteria.2. Add 200 µL of Buffer SA and vortex to mix.Note: In the case of plant leaves and animal tissues, they should be ground with a pestle and mortar as much as possible: in the case of plant seeds, they should be crushed and finely ground beforehand; bacterial and 1-3 mm rat-tail samples can be directly vortex lysed.3. Add 10µL of Proteinase K, mix well, incubate at 56℃ for 10 minutes, and treat at 95℃ for 5 minutes.Note: 1) In the case of animal tissue samples, the incubation time at 56°C may be extended to 30 minutes as appropriate; if there is any incompletely digested tissue, it should be removed as thoroughly as possible after centrifugation in the next step.2) Be careful not to exceed 5 minutes when treating at 95°C.4. 13,000 rpm (~17,900 x g), centrifugation for 5 minutes.5. Transfer the supernatant to a new centrifuge tube (self-prepared) and use it directly for PCR amplification, or store the solution at 4℃ or -20℃.6. PCR amplification:1) PCR reaction system:The following examples are conventional PCR reaction systems and reaction conditions, which should be improved and optimized according to the template, primer structure and target fragment size in actual operation.reagents20 µL systemfinal concentration2×PCR MasterMix10 µL1×Forward Primer, 10 µM1 µL0.4 µMReverse Primer, 10 µM1 µL0.4 µMTemplate DNA1-2 µL RNase-free Waterup to 20 µLNote: Please use the final concentration of 0.2-0.6µM as a reference for setting the range of primer concentration. If the amplification efficiency is not high, the concentration of primer can be increased; if a non-specific reaction occurs, the concentration of primer can be decreased, thus optimizing the reaction system.2）PCR reaction conditions:movetemptimingpremutability94°C2mindenaturation94°C30sannealing (metallurgy)55-65°C30s30-40 cyclesreach72°C60sultimate extension72°C5minNote: 1) In general, the annealing temperature is 5℃ lower than the melting temperature of the amplification primer Tm, and the annealing time is generally 30-60 seconds. When the desired amplification efficiency cannot be obtained, the annealing temperature should be lowered appropriately; when a non-specific reaction occurs, the annealing temperature should be raised, thus optimizing the reaction conditions.(2) The extension time is set according to the size of the fragment to be amplified, and the amplification efficiency of Taq DNA Polymerase included in this product is 1kb/30s. 3) The number of cycles can be set according to the downstream application of the amplification product. If the number of cycles is too low, the amplification is insufficient; if the number of cycles is high, the chance of mismatch will increase and the non-specific background will be serious. Therefore, the number of cycles should be minimized under the premise of ensuring the product yield.(3) Result detection: 5 µL of reaction product was taken at the end of the reaction and directly detected by agarose gel electrophoresis... 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 | Store at -20°C. Please refer to protocols | N665925 Component 1 mL 5 mL Storage N665925A 2×SYBR qPCR Master Mix 1 1 mL 5 mL -20℃. Avoid freeze/ Thaw cycle. N665925B qPCR Primer Mix 1 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665925C DNA Standard I 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665925 Component 1 mL 5 mL Storage N665925A 2×SYBR qPCR Master Mix 1 1 mL 5 mL -20℃. Avoid freeze/ Thaw cycle. N665925B qPCR Primer Mix 1 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665925C DNA Standard I 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665925D DNA Standard II 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665925E DNA Standard III 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665925F DNA Standard IV 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665925G DNA Standard V 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665925H 50×High ROX 40 µL 200 µL -20℃. Avoid freeze/ Thaw cycle.Product IntroductionThis product is a real-time fluorescence quantitative PCR of the products after NGS library construction using a dye method (SYBR Green I).(qPCR). The kit provides the reaction mixes, DNA primer mixtures, standards and sample dilutions required for the qPCR process, making the reagent system complete and easy to use. The fluorescent dye SYBR Green I contained in the reaction mixture can bind to all double-stranded DNA; the GoldStar Taq DNA Polymerase used is a chemically modified new high-efficiency hot-start polymerase, and the activation of the enzyme needs to be incubated at 95℃ for 10 minutes. the product has high specificity, high amplification efficiency, and is able to quickly and accurately quantify the concentration of the constructed libraries. The product is highly specific and efficient in amplification, and can quickly and accurately quantify the concentration of the constructed library.ROX dye is used to correct the fluorescence signal error generated between wells of a quantitative PCR instrument, and is generally used in Real Time PCR amplifiers from ABI, Stratagene, and other companies. The excitation optics vary from instrument to instrument, so the concentration of ROX dye must be matched to the corresponding fluorescence quantitative PCR instrument.Instruments that do not require ROX calibration: Roche LightCycler 480, Roche LightCyler 96, Bio-rad iCyler iQ, iQ5, CFX96, etc.Instruments requiring Low ROX calibration: ABI Prism7500/7500 Fast, QuantStudio®3 System, QuantStudio®5 System, QuantStudio®6 Flex System, QuantStudio®7 Flex System, ViiA 7 System, Stratagene Mx3000/Mx3005P, Corbett Rotor Gene 3000, and others.Instruments requiring High ROX calibration: ABI Prism7000/7300/7700/7900, Eppendorf, ABI Step One/Step One Plus, etc.Note: High Rox and Low Rox are formulated as described in Use 2.Scope of applicationThis product is designed for absolute quantification of the concentration of Ion torrent platform second generation sequencing libraries. The end of the library contains Ion torrent P5 and P7 microarray binding sequences, the length of which does not exceed 1kb, and the concentration is not less than 0.005pM can be used to perform quantitative experiments with this product. The qPCR Primer Mix provided in the kit contains the following two primer sequences:Primer 1:5'-CCA TCT CAT CCC TGC GTG TC - 3' Primer 2: 5'-CCT CTC TAT GGG CAG TCG GTG AT-3'The primer sequence can be used in advance to confirm whether the library can be amplified by that primer pair.Usage1. Amplification template preparationThe library samples to be detected were diluted with TE (10 mM Tris-Cl, pH 8.0, 1 mM EDTA), and the concentration after dilution was as close as possible to the range of 0.05-50 pM. 4°C on ice was set aside.2. qPCR reaction system preparationThe desired cryopreservation reagent is pre-melted completely and mixed by inverting several times before preparation, then centrifuged briefly and set aside.The base reaction system for 20 µl was as follows:Reagent20 µl Reaction system2×SYBR qPCR MasterMix10 µlqPCR Primer Mix 10.8 µlTemplate4 µlddH₂O5.2 µlDescription: High Rox model: add 1 µl High Rox per 50 µl of reaction system;Low Rox model: 1 µl High Rox per 500 µl of reaction system.Prepare a sufficient amount of reaction system mixture according to the need, mix well and add to the reaction wells in a volume of 16 µl per well, add the same volume of TE to the blank control, and then add the prepared standards and diluted samples to the corresponding reaction wells in a volume of 4 µl/well. It is recommended to use 20 µl reaction system, if you need to carry out a smaller system reaction, the system components can be reduced in equal proportion.3. qPCR reaction program1) Please use 60-64℃ as a reference for setting range of annealing temperature, and increase the annealing temperature when non-specific reaction occurs.2) If the average length of the library is greater than 700bp, the annealing/extension time should be increased appropriately.data analysis1. Standard curve productionThe standard curve was plotted using Ct values in the valid range. The standard curve correlation coefficient R2 should not be less than 0.99 and the slope should lie between -3.1 and -3.6. If the standard curve parameters are not reasonable, it is recommended to repeat the experiment.DNA Standard NameDNA Standard ConcentrationDNA Standard I50 pMDNA Standard II5 pMDNA Standard III0.5 pMDNA Standard IV0.05 pMDNA Standard V0.005 pM2. Library concentration calculationThe difference in Ct between the three replicate wells of the experiment should be no more than 0.2, otherwise the invalid data should be deleted or the experiment should be repeated. Do not use the Ct outside the valid Ct range of the standard curve to calculate the concentration of the diluted libraries. Please refer to the data processing Excel of this product for the specific library concentration calculation method.matters needing attention1. Before testing, these instructions should be read in detail. It should be operated by personnel with professional experience or qualified by training.2. For use, please mix gently by turning up and down, avoid foaming as much as possible, and use it after centrifugation for a short period of time.3. Avoid repeated freezing and thawing of the product, repeated freezing and thawing may degrade the performance of the product.4. When preparing the reaction solution, please use new or non-contaminated tips and centrifuge tubes to prevent contamination as much as possible... Read More |