| 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 | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export | CFDASE cell proliferation and tracking detection kit is a kit for cell proliferation and tracking detection based on CFDA se. This kit is composed of CFDASE powder, solvent and staining buffer. CFDASE is a derivative of fluorescein diacetate (FDA), which has cell membrane permeability and CFDASE cell proliferation and tracking detection kit is a kit for cell proliferation and tracking detection based on CFDA se. This kit is composed of CFDASE powder, solvent and staining buffer. CFDASE is a derivative of fluorescein diacetate (FDA), which has cell membrane permeability and does not have fluorescence luminescence. When CFDASE penetrates the cell membrane into living cells, it can be catalysed by esterases in the cytosol to produce carboxyfluorescein succinimidyl ester (CFSE), which can emit strong green fluorescence, cannot penetrate the cell membrane, and can remain intact in the cell. CFSE can also spontaneously and irreversibly covalently bind to intracellular amino groups to couple to cellular proteins. Meanwhile, the excess and uncoupled CFDASE returned to the extracellular medium by passive diffusion and was cleared by subsequent washing steps. The fluorescence of non dividing cells labeled by CFDASE is very stable, and the stable labeling time can reach several months, so it is very suitable for cell community analysis. The fluorescence of CFDASE labeled cells is very homogeneous, which is superior to other cell tracking fluorescent probes used previously, such as PKH26, and the fluorescence distribution of the divided progeny cells is also very uniform. In the process of cell division and proliferation, CFSE labeled fluorescence can be evenly distributed to the two progeny cells, and the fluorescence intensity becomes half of the parental cells. According to the fluorescence intensity, flow cytometer (FL1 channel) can detect undivided cells, cells that divide once (1 / 2 of the fluorescence intensity), twice (1 / 4 of the fluorescence intensity), three times (1 / 8 of the fluorescence intensity), and cells that divide more times. CFDASE can detect up to eight or more cleavages. CFDASE labeled cells can be used for proliferation studies in vitro and in vivo, and have the function of not staining adjacent cells. CFDASE is most commonly used to detect the proliferation of lymphocytes, and can also be used to detect the proliferation of fibroblasts, NK cells and other cells. CFDASE labeled cells showed green fluorescence. In addition to flow cytometry to detect cell proliferation, fluorescence microscopy can also be used for homogeneous staining of cell tracking observation.Components:ComponentsC598182-20TC598182-500TA. CFDA SE1 tube1 tubex5B.CFDA SE solvent20 µL500 µLC.10x CFDA SE Buffer1 mL x250 mLMatters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. CFDA and Se are easily hydrolyzed and will deteriorate quickly in aqueous solution. Please avoid contact with water during use. Contact with water during the process of labeling cells is within the permitted range. 3. CFDA se solvent will solidify at lower temperatures such as 4 º C and ice bath and stick to the bottom, wall or cover of the centrifugal tube. It can be used after incubating in a 20-25 º C water bath for a while until it is completely dissolved. 4. this kit optimizes the CFDA se staining system, but users are advised to explore the optimal working concentration and staining time according to their own cell type, culture conditions and application direction. Different cells have different lactonase activities, so the staining effect is different. 5. fluorescent dyes have quenching problems. Please avoid light during operation to slow down fluorescence quenching. 6. for your safety and health, please wear experimental clothes and disposable gloves.Usage method:1. Preparation of reagents(1) Preparation of CFDA SE storage solution: Take one tube of CFDA SE provided in the reagent kit and restore it to room temperature. Instantly centrifuge to allow the powder to fully settle to the bottom of the tube. Add 100 µ L CFDA SE solvent (add 20 µ L CFDA SE solvent) to it and dissolve it thoroughly to prepare CFDA SE storage solution (1000 ×). Prepared CFDA SE storage solution, stored at -20 ℃ in the dark, with a shelf life of two months- Storing at 70 ℃ in the dark can extend the usage time appropriately.(2) Preparation of CFDA SE Buffer: Dilute 10 x CFDA SE Buffer to 1 x with sterile cell culture grade water as needed. The prepared 1 × CFDA SE Buffer can be stored at 4 ℃ and can be stored at -20 ℃ if not in use for a long time.2. Marking and detection(1) Centrifuge the collected cells, use 1 mL 1 × CFDA SE Buffer to re suspend the cells in a 15 mL centrifuge tube, and adjust the cell concentration to 1-5 × 106 cells/mL.(2) Preparation of CFDA SE working solution: Dilute the CFDA SE storage solution (1000 ×) with 1 × CFDA SE Buffer to 2 ×.(3) Staining: Add 1 mL of CFDA SE working solution (2 x) to 1 mL of cell suspension to be labeled, invert and mix well, and incubate at 37 ℃ for 10 minutes.(4) Immediately add 5 times the volume of preheated complete culture medium (including serum) to the centrifuge tube, invert and mix well to terminate the labeling reaction.(5) Centrifuge at 1000 rpm for 5 minutes at room temperature to remove the supernatant, then wash once with 5-10 mL of complete culture medium.(6) Add 5-10 mL of complete culture medium and incubate at 37 ℃ for 5 minutes to promote the residence of CFDA SE in the cells and the entry of unreacted CFDA SE into the complete cell culture medium. Centrifuge at 1000 rpm for 5 minutes at room temperature to remove the supernatant and complete the final wash.(7) Subsequently, the cells can be cultured using the normal cultivation method. The labeling effect can be directly observed under a fluorescence microscope, or cell proliferation can be detected by flow cytometry after appropriate cultivation time, showing green fluorescence. The labeled cells can also be used for transplantation in live animals and for fluorescence tracing.Note: a If cell fixation is required, use aldehyde fixatives such as 4% paraformaldehyde to fix at room temperature for 15 minutes; If additional labeling such as antibody labeling is required afterwards, please permeabilize the cells with ice acetone for 10 minutes. b. The optimal labeling concentration and incubation time for CFDA SE vary for different cells. The initial experiment can be conducted according to the experimental steps. If the effect is not satisfactory, it is recommended to adjust the staining concentration and incubation time to achieve the best labeling effect.Scope of application：Cell proliferation assay... Read More | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export | Inquire |