| Description | Animal liver and kidneys are the main organs for amino acid metabolism. Therefore, changes in urinary amino acids best reflect the physiological state of the liver and kidneys. Additionally, amino acid levels can indicate conditions such as burns and typhoid fever. The amino acid content in plants Animal liver and kidneys are the main organs for amino acid metabolism. Therefore, changes in urinary amino acids best reflect the physiological state of the liver and kidneys. Additionally, amino acid levels can indicate conditions such as burns and typhoid fever. The amino acid content in plants is significant for studying nitrogen metabolism changes under different conditions and during various growth and development stages, as well as for understanding nitrogen absorption, transport, assimilation, and nutritional status in plants.Detection Principle: The α-amino group of amino acids reacts with ninhydrin hydrate to produce a blue-purple compound with a characteristic absorption peak at 570 nm. The amino acid content is calculated by measuring the absorbance at 570 nm.Detection Range: 0.625 - 40 µmol/mLSensitivity: 0.5 µmol/mLApplicable Samples: Serum (plasma), animal/plant tissues, cells, cell culture supernatants, bacteria, urineG1501758Component96TStorageG1501758AExtraction Buffer100 mL2-8℃G1501758BAssay Buffer10 mL2-8℃G1501758CSubstrate1EA2-8℃. Store in the dark.G1501758DStandard (10mg Cysteine)1EA2-8℃. Store in the dark.User-Prepared Instruments and ReagentsMicroplate reader or visible spectrophotometer (capable of measuring absorbance at 570 nm)96-well plate or micro glass cuvettes, adjustable micropipettes and tipsRefrigerated centrifuge, water bathDeionized water, EthanolHomogenizer (for tissue samples)Experimental Procedure1. Reagent PreparationReagent NameReagent PreparationNotesExtraction BufferReady-to-use; Equilibrate to room temperature before use.Store at 4°C.Assay BufferReady-to-use; Equilibrate to room temperature before use.Store at 4°C. Toxic and irritant. Perform experiments in a fume hood.SubstrateToxic and irritant. Perform experiments in a fume hood.Working SubstratePrepare before use: Dissolve in 4 mL of 95% Ethanol.Unused dissolved substrate can be stored at 4°C protected from light for one week. For long-term storage, aliquot and store at -20°C protected from light for one month. Avoid repeated freeze-thaw cycles.StandardPrepare before use: Add 2.066 mL deionized water to dissolve completely, resulting in a 40 µmol/mL stock.Unused dissolved standard can be stored at 4°C for one week. For long-term storage, aliquot and store at -20°C for one month. Avoid repeated freeze-thaw cycles.2. Standard Curve SetupDilute the 40 µmol/mL standard stock solution with deionized water to concentrations of 20, 10, 5, 2.5, 1.25, and 0.625 µmol/mL as shown in the table below.TubeStandard VolumeDeionized Water Volume (µL)Standard Concentration (µmol/mL)Std.1200µL of 40µmol/mL040Std.2100µL of Std.110020Std.3100µL of Std.210010Std.4100µL of Std.31005Std.5100µL of Std.41002.5Std.6100µL of Std.51001.25Std.7100µL of Std.61000.625Note: The standard curve must be generated with each experiment. Diluted standard solutions are unstable and must be used within 4 hours.3. Sample PreparationNote: Fresh samples are recommended. If not used immediately, samples can be stored at -80°C for up to one month.3.1 Animal TissueWeigh approximately 0.1 g of tissue. Add 1 mL of Extraction Buffer and homogenize thoroughly at room temperature. Transfer the homogenate to a 1.5 mL microcentrifuge tube. Cap tightly (to prevent moisture loss) and incubate in a boiling water bath for 15 minutes. Cool with tap water. Centrifuge at 10,000 rpm for 10 minutes at room temperature. Collect the supernatant for assay.3.2 Plant TissueWeigh approximately 0.1 g of tissue. Add 1 mL of Extraction Buffer and grind. Sonicate for 5 minutes at room temperature (power 20% or 200W, pulse 3s on, 7s off, repeat 30 times). Transfer to a 1.5 mL microcentrifuge tube. Cap tightly (to prevent moisture loss) and incubate in a boiling water bath for 15 minutes. Cool with tap water. Centrifuge at 10,000 rpm for 10 minutes at room temperature. Collect the supernatant for assay.3.3 Cells or BacteriaCollect 5 million cells or bacteria into a centrifuge tube. Wash cells with cold PBS, centrifuge, and discard the supernatant. Add 1 mL of Extraction Buffer. Sonicate for 5 minutes at room temperature (power 20% or 200W, pulse 3s on, 7s off, repeat 30 times). Transfer to a 1.5 mL microcentrifuge tube. Cap tightly (to prevent moisture loss) and incubate in a boiling water bath for 15 minutes. Cool with tap water. Centrifuge at 10,000 rpm for 10 minutes at room temperature. Collect the supernatant for assay.3.4 Serum (Plasma), Cell Culture Supernatant, Urine, and Other LiquidsPipette 0.5 mL of the liquid sample and add 0.5 mL of Extraction Buffer. Cap tightly (to prevent moisture loss) and incubate in a boiling water bath for 15 minutes. Cool with tap water. Centrifuge at 10,000 rpm for 10 minutes at room temperature. Collect the supernatant for assay.Note: If protein concentration measurement is required, use Aladdin's BCA Protein Quantification Kit (B665595) or Ready-to-Use BCA Protein Quantification Kit (R1491648).4. Assay Steps4.1 Preheat the microplate reader or visible spectrophotometer for at least 30 minutes. Set the wavelength to 570 nm. For spectrophotometers, zero the instrument with deionized water.4.2 Sample Measurement (Add reagents sequentially into microcentrifuge tubes as below):ReagentBlank Tube (µL)Standard Tube (µL)Test Tube (µL)Deionized Water1000Standard (various conc.)0100Sample0010Working Substrate202020Assay Buffer5050504.3 Mix well and cap the tubes tightly (to prevent moisture loss). Incubate in a boiling water bath for 5 minutes. Cool in tap water for 10 seconds. Add 120 µL of 60% ethanol to each tube and invert several times to mix. Transfer 150 µL from each tube to the corresponding wells of a 96-well plate or micro glass cuvette. Measure the absorbance at 570 nm, recorded as A blank, A standard, and A test. Calculate ΔA test = A test - A blank and ΔA standard = A standard - A blank (The blank tube only needs to be prepared once). All measurements must be completed within 30 minutes after color development. Note:It is recommended to perform a preliminary test with 2-3 samples expected to have significant differences before the formal experiment. If A <sub> test </sub> is greater than 2.0, dilute the sample further with deionized water and multiply the result by the dilution factor.Proline and hydroxyproline do not produce an absorption peak at 570 nm when reacting with ninhydrin. Therefore, the results measured at 570 nm do not include these two amino acids.5. Calculation of ResultsNote: We provide two formulas, including the derived formula and a simplified version. They are equivalent. It is recommended to use the simplified formula in bold for final calculation.5.1 Standard Curve PlottingPlot the standard concentration (y-axis) against ΔA standard (x-axis) to generate the standard curve. Substitute ΔA test into the standard curve equation to calculate y (µmol/mL).5.2 Sample Amino Acid Content Calculation(1) Based on Sample WeightAmino Acid Content (µmol/g weight) = y ÷ (W ÷ V<sub>extraction</sub>) × n = y ÷ W × n(2) Based on Protein ConcentrationAmino Acid Content (µmol/mg prot) = y ÷ Cpr × n(3) Based on Bacterial or Cell CountAmino Acid Content (µmol/10⁴ cells) = y ÷ (Count ÷ V<sub>extraction</sub>) × n = y ÷ 500 × n = 0.002 × y × n(4) Based on Liquid VolumeAmino Acid Content (µmol/mL) = y × 2 × nParameter Definitions:W: Sample weight (g)V extraction : Volume of Extraction Buffer added (1 mL)n: Sample dilution factorCpr: Protein concentration of the supernatant (mg/mL)500: Total number of bacteria or cells (5 million)2: Dilution factor for liquid samples [(0.5 mL sample + 0.5 mL Buffer) / 0.5 mL sample = 2]6. Representative ResultsTypical Standard Curve: y = 20.349x - 0.423, R² = 0.9971 Figure 1: Total Amino Acid Standard Curve Precautions1. Biochemical reagents are generally irritating, biologically toxic, etc. For your safety and health, please use appropriate biosafety precautions throughout the experiment, including wearing lab coats, masks, gloves, head covers, etc. Perform experiments in a fume hood or biosafety cabinet.2. This product is for research use only. Not for use in clinical diagnosis... Read More | Inquire | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export | This product can rapidly, gently, and efficiently lyse mammalian cells, effectively extracting cytoplasmic and nuclear proteins. This reagent uses a mild formula to ensure that the extracted protein maintains biological activity and can be applied to various protein analysis experiments, such as This product can rapidly, gently, and efficiently lyse mammalian cells, effectively extracting cytoplasmic and nuclear proteins. This reagent uses a mild formula to ensure that the extracted protein maintains biological activity and can be applied to various protein analysis experiments, such as reporter gene and enzyme activity determination, immune detection, protein purification, etc. The extracted protein can be quantitatively analyzed using the BCA method. The reagent kit contains a mixture of protease inhibitors, which can effectively prevent protein degradation during the protein extraction process.M665813Component100 TStorageM665813AMammalian Protein Extraction Reagent100 mLRTM665813BProtease Inhibitor Cocktail (100×)1 mL-20℃. Avoid freeze/thaw cycle. precautions1. This product can effectively lyse adherent cells cultured on cell culture plates (without scraping) and suspended cells collected by centrifugation, with higher extraction efficiency than repeated freeze-thaw or ultrasound methods. But for the extraction of tissue proteins, it is recommended to use the tissue protein extraction kit (CW0891).The optimal dosage for protein extraction from adherent cells is listed in Table 1. Collecting cells first can reduce the amount of reagents used to obtain higher protein concentrations.3. The amount of extraction reagents used can also be estimated based on the number of cells. If 2 × 106 Hela cells weigh about 20 mg, 200 need to be added µ Extract reagents.4. The protein extracted from this product can be quantitatively analyzed using the BCA method.Operation steps● Protein extraction from adherent cells1. Please remove the required Mammalian Protein Extraction Agent for pre cooling before protein extraction.2. Carefully pour out the culture medium of adherent cells and rinse the cells with PBS.3. Add an appropriate amount of Mammalian Protein Extraction Reagent (add Protein Inhibitor Cocktail in a 1:99 ratio 2-3 minutes before protein extraction), blow adherent cells on ice with a gun tip, transfer the lysate to a centrifuge tube, incubate on ice for 20 minutes, and allow the cells to fully lyse (please refer to Appendix 1 for the amount of reagent used, and the time for placing on ice should be adjusted according to different cell types). 4. Centrifuge at 14000 × g for 5-10 minutes.5. Transfer the supernatant to a new tube for further analysis. ● Suspension cell protein extraction1. Please remove the required Mammalian Protein Extraction Agent for pre cooling before protein extraction.2. Suspend 2500 × g of cells, centrifuge for 10 minutes, and discard the supernatant. Rinse cells with PBS. 2500 × g, centrifuge for 10 minutes, discard the supernatant.3. Add an appropriate amount of Mammalian Protein Extraction Agent, and 2-3 minutes before protein extraction, add Protein Inhibitor Cocktail in a ratio of 1:99, which is 1 x working solution.4. Add at least 1 ml of 1x working solution to every 100 mg of cells. If the extracted sample size is large, a small amount of 1x working solution can be used to resuspend the cells first, and then the remaining working solution can be added.5. After blowing evenly, place it on ice for 20 minutes to allow the cells to fully lyse (the time for placing it on ice should be adjusted according to different cell types). 6. Centrifuge at 14000 × g for 15 minutes.7. Transfer the supernatant to a new tube for further analysis.Table 1. Recommended usage of extraction reagents Cell culture plate type or dish type Extraction reagent usage 100 mm 500-1,000 µl 60 mm 250-500 µl 6-well culture plate 200-400 µl /well 24-well culture plate 100-200 µl /well 96-well culture plate 50-100 µl /well Table 2. Common Problems and Solutions Problem Possible reasons Resolvent Low extraction rate Low protein expression level Optimize transfection system Low extraction rate Insufficient reagent usage Increase the usage of extraction reagents Low extraction rate Reagent unable to dissolve cell membrane Increase cracking time or increase shaking amplitude Unable to obtain membrane protein This product is more suitable for extracting nuclear plasma protein Using eukaryotic cell membrane protein extraction kit... Read More | Products contentN665989Component240 TStorageN665989AIndex N501 Primers for Illumina240 µL-20℃. Avoid freeze/ Thaw cycle.N665989BlIndex N901-N924 Primers for Illumina24×10 µL-20℃. Avoid freeze/ Thaw cycle.Note: The amount of individual primers used is 1 µl, each N7-endProducts contentN665989Component240 TStorageN665989AIndex N501 Primers for Illumina240 µL-20℃. Avoid freeze/ Thaw cycle.N665989BlIndex N901-N924 Primers for Illumina24×10 µL-20℃. Avoid freeze/ Thaw cycle.Note: The amount of individual primers used is 1 µl, each N7-end primer can perform 10 DNA library constructs, and each kit can perform 240 DNA library constructs. Products IntroductionThis kit is a companion kit to the transposase-based Rapid DNA Library Construction Kit for Illumina platform library construction. Each kit contains one N5 primer and 24 N7 primers, which can be used to prepare 24 different single-ended Index libraries. All reagents provided in the kits have been subjected to stringent quality control and functional validation to maximize the stability and reproducibility of library construction. The libraries can be used for sequencing 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 with 1.5 ml centrifuge tubes;Tip: It is recommended to use a high quality filter tip to prevent contamination of 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. ProcedureFor 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 Primer for IlluminaIndex N901-N996 Primer for Illumina... Read More |