| 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 | 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 | Product introduction：Product introduction：Cell Cycle Assay Kit Plus ( Cell Cycle Assay Kit Plus ) has certain applicability for live cells and fixed cell cycle detection. For different types of cells, whether it is applicable or not needs to be determined after testing. Cell Cycle Product introduction：Product introduction：Cell Cycle Assay Kit Plus ( Cell Cycle Assay Kit Plus ) has certain applicability for live cells and fixed cell cycle detection. For different types of cells, whether it is applicable or not needs to be determined after testing. Cell Cycle Assay Kit Plus ( Cell Cycle Assay Kit Plus ) uses RedNucleus I staining to detect cell cycle. RedNucleus I is a far-infrared nucleic acid dye with cell membrane permeability, which can quickly enter living cells, specifically bind to DNA, and perform cell cycle detection on living cells without RNase digestion. Compared with the traditional PI staining method, the cells do not need to be broken or fixed, and the operation is simpler. RedNucleus I is a fluorescent dye of double-stranded DNA, and the fluorescence intensity after binding to double-stranded DNA is proportional to the content of double-stranded DNA. The intracellular DNA content can be measured by flow cytometry, and then the cell cycle analysis can be carried out according to the distribution of DNA content. After RedNucleus I staining, assuming that the fluorescence intensity of G0 / G1 phase cells is 1, the theoretical value of the fluorescence intensity of G2 / M phase cells containing two copies of genomic DNA is 2, and the fluorescence intensity of S phase cells undergoing DNA replication is between 1-2. In addition, RedNucleus I is compatible with dyes such as Horizon BV / BUV, FITC and R-PE, and can be periodically detected after sample staining.The kit is usually used to detect the cell cycle of cultured adherent or suspended cells. If it is used for cell cycle detection of tissues, the tissues must be digested into a single cell state.Matters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. this product is applicable to the detection of living cells and fixed cell cycle with certain limitations. Whether it is applicable to different types of cells needs to be determined after testing. If fixation is needed, it is recommended to use ice bath pre cooling 75-80% ethanol -20 ℃ to fix cells overnight. 3. fluorescent dyes have quenching problems. Please try to avoid light during storage and use to slow down fluorescence quenching. 4. for your safety and health, please wear experimental clothes and disposable gloves.Instruction： Experimental materials ( self-provided )：①cell lines or other cell samples ( self-prepared ) ；②This kit ; ③ trypsin ( self-prepared ) ;④ Cell culture medium containing FBS ( self-prepared ) ; Experimental procedure： 1.Preparation of cell samples : ( 1 ) ( This step is for adherent cells, if suspended cells, can be carried out directly step ( 2 ) ) Digest cells with trypsin, add cell culture medium, gently blow away cells, collected into the centrifuge tube. Note : The number of cells on the machine needs to reach 50,000 and above, so the initial number of cells collected needs to be sufficient. ( 2 ) Centrifuged about 1000 g for 3-5 min to precipitate cells. Carefully remove the supernatant, add about 1 mL of ice bath pre-cooled 1 × staining buffer ( 10 × staining buffer diluted with diH2O at 1 : 10 ), re-suspend the cells. Repeat once. ( 3 ) Centrifuged about 1000 g for 3-5 min to precipitate cells. After the supernatant was discarded, 1 mL of culture medium was added to re-suspend the cells ( for fixed cells, 1 × PBS can also be used to re-suspend ). Gently flick the bottom of the centrifuge tube to properly disperse the cells to avoid cell aggregation. 2.Staining : 4 µL of RedNucleus I staining solution was added to each tube of cell samples, slowly and fully mixed, and incubated at room temperature in dark for 20 min ( or incubated at 37 ° C in dark for 5-10 min ). The optimal incubation time of different cells is different, and the staining time can be adjusted and optimized according to the actual staining effect to obtain a more ideal staining effect. 3.Flow cytometry detection and analysis : Excited at 638 nm by flow cytometry, it is recommended to detect in RL3 or FL4 channels, or use RL1 and RL2 channels. Cell DNA content analysis and light scattering analysis were performed using appropriate analysis software.Scope of application：Cell cycle detection... Read More | Inquire | The miRNA extraction kit is specifically designed to isolate and purify miRNAs from various animal tissues, plant tissues, cells, serum, plasma and other samples. It can also extract small molecule RNAs such as siRNA and snRNA that are less than 200 nt, and can also be used for the extraction of The miRNA extraction kit is specifically designed to isolate and purify miRNAs from various animal tissues, plant tissues, cells, serum, plasma and other samples. It can also extract small molecule RNAs such as siRNA and snRNA that are less than 200 nt, and can also be used for the extraction of total RNA. This product combines phenol/guanidine lysis technology and silicon matrix membrane purification technology. The unique lysis solution can effectively inhibit RNases while removing most of DNA and proteins from cell or tissue samples through organic extraction. For some sensitive downstream experiments, if miRNA enrichment is required, this kit can be used to enrich miRNA separately. This product is suitable for a wide range of samples, with high purity of prepared RNA, and can be directly used for sensitive downstream applications, such as Northern Blot analysis, Real Time PCR, Microarray Analysis, etc. M665531Component50 TStorageM665531ATRIzon Reagent60 mL2-8℃. Protect from ligt.M665531BBuffer RWT (concentrate)15 mLRTM665531CBuffer RW2 (concentrate)11 mLRTM665531DRNase-Free Water10 mLRTM665531ESpin Columns RM with Collection Tubes50 setsRTM665531FSpin Columns RS with Collection Tubes50 setsRTM665531GRNase-Free Centrifuge Tubes (1.5 mL)50 EART Self prepared reagents: chloroform, anhydrous ethanol (newly opened or dedicated for RNA extraction).Preparation and important precautions before the experiment: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.2. The extracted samples should avoid repeated freeze-thaw cycles, otherwise it will affect the quantity and quality of miRNA extraction.Before the first use, anhydrous ethanol should be added to Buffer RWT and Buffer RW2 according to the instructions on the reagent bottle label.4. All centrifugation steps should be carried out at room temperature unless otherwise specified, and all operation steps should be carried out quickly.Operation steps:Protocol A: miRNA enrichment (can be directly used for sensitive downstream experiments)1. Sample processing1a Organization: Grind the organization in liquid nitrogen. Add 1 ml of TRIzon Reagent to every 30-50 mg of tissue, shake and mix well. The sample volume shall not exceed one tenth of the volume of TRIzon Reagent.1b Single layer culture of cells: Remove the culture medium, add TRIzon Reagent, and add 1 ml of TRIzon Reagent every 10 cm2 (the amount of lysis solution depends on the area of the culture bottle).1c Cell suspension: Centrifuge to obtain cell precipitate, discard supernatant. Add 1 ml of TRIzon Reagent to every 5 x 106-1 x 107 cells (cells do not require washing).1d Plasma or serum: Take 200 µ Add 5 times the volume of TRIzon Reagent to plasma or serum samples, shake and mix well for 30 seconds.2. After adding TRIzon Reagent to the sample, blow it repeatedly several times to fully crack it. Leave at room temperature for 5 minutes to completely separate the protein nucleic acid complex.3. Optional steps: Centrifuge at 4 ℃ 12000 rpm (~13400 × g) for 5 minutes, take the supernatant, and transfer it to a new centrifuge tube (provided by oneself) (if the sample contains more proteins, fats, polysaccharides, etc., this step can be performed).4. Add chloroform to the supernatant and add 200 to every 1 ml of TRIzon Reagent used µ Chloroform, cover the tube, vigorously shake for 15 seconds, and let it sit at room temperature for 5 minutes.Centrifuge at 5.4 ℃ and 12000 rpm for 15 minutes. The sample is divided into three layers: red organic phase, middle layer, and colorless aqueous phase. Transfer the upper colorless aqueous phase to a new centrifuge tube (self prepared).6. Add 1/3 volume of anhydrous ethanol to the solution obtained in step 5, mix well, and transfer the obtained solution and precipitate together into the adsorption column RM (Spin Columns RM) that has been loaded into the collection tube. If you cannot add all the solution to the adsorption column at once, please transfer it multiple times. Centrifuge at 12000 rpm for 30 seconds, discard the adsorption column RM after centrifugation, and retain the effluent.7. Add 2/3 times the volume of anhydrous ethanol to the solution obtained in step 6 and mix well.8. Transfer the solution and precipitate obtained from the previous step into the adsorption column RS (Spin Columns RS) that has been loaded into the collection tube. If you cannot add all the solution to the adsorption column at once, please transfer it multiple times. Centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RS back into the collection tube.9. Add 700 to the adsorption column RS µ L Buffer RWT (check if anhydrous ethanol is added before use), centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RS back into the collection tube.10. Add 500 to the adsorption column RS µ Buffer RW2 (check if anhydrous ethanol is added before use), centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RS back into the collection tube.11. Repeat step 10.12. Centrifuge at 12000 rpm for 1 minute and discard the waste liquid from the collection tube. Place the adsorption column RS at room temperature for a few minutes to thoroughly air dry. Note: The purpose of this step is to remove residual ethanol from the adsorption column RS, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).13. Place the adsorption column RS in a new RNase free centrifuge tube and add 30-50 to the middle of the adsorption column µ Place RNase Free Water at room temperature for 1 minute, centrifuge at 12000 rpm for 1 minute, collect RNA solution, and store the obtained RNA solution at -70 ℃ to prevent degradation.Attention:1) The volume of RNase Free Water should not be less than 30 µ l. Small volume affects the recovery rate.2) If you want to increase RNA production, you can use 30-50 µ Repeat step 13 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 RS and repeat step 13Protocol B: Extraction of total RNA (including miRNA and other small molecule RNAs<200 nt), steps 1-5 are the same as protocol A.6. Add 1.25 times the volume of anhydrous ethanol to the solution obtained in step 5 and mix well.7. Transfer the solution and precipitate obtained from the previous step into the spin columns RM that have been loaded into the collection tube. If you cannot add all the solution to the adsorption column RM at once, please transfer it multiple times. Centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RM back into the collection tube.8. Add 700 to the adsorption column RM µ L Buffer RWT (check if anhydrous ethanol is added before use), centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RM back into the collection tube.9. Add 500 to the adsorption column RM µ Buffer RW2 (check if anhydrous ethanol is added before use), centrifuge at 12000 rpm for 30 seconds, discard the waste liquid in the collection tube, and place the adsorption column RM back into the collection tube.10. Repeat step 9.11. Centrifuge at 12000 rpm for 1 minute and discard the waste liquid from the collection tube. Place the adsorption column RM at room temperature for a few minutes to thoroughly air dry. Attention: The purpose of this step is to remove residual ethanol from the adsorption column RM, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).12. Transfer the adsorption column RM into a new RNase free centrifuge tube and add 30-50 to the middle of the adsorption column µ Place RNase Free Water at room temperature for 1 minute, centrifuge at 12000 rpm for 1 minute, collect RNA solution, and store the obtained RNA solution at -70 ℃ to prevent degradation. Attention: 1) The volume of RNase Free Water should not be less than 30 µ l. Small volume affects the recovery rate.2) If you want to increase RNA production, you can use 30-50 µ Repeat step 12 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 RM and repeat step 12... Read More |