| 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 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 | Products contentN665954Component24 T96 TStorageN665954ATPS V136 µL144 µL-20℃. Avoid freeze/thaw cycle.N665954B5×FA Reaction Buffer96 µL384 µL-20℃. Avoid freeze/thaw cycle.N665954CTS Buffer72 µL288 µL-20℃. Avoid freeze/thaw cycle.N665954D2× Products contentN665954Component24 T96 TStorageN665954ATPS V136 µL144 µL-20℃. Avoid freeze/thaw cycle.N665954B5×FA Reaction Buffer96 µL384 µL-20℃. Avoid freeze/thaw cycle.N665954CTS Buffer72 µL288 µL-20℃. Avoid freeze/thaw cycle.N665954D2× PCR Mix600 µL2×1.2 mL-20℃. Avoid freeze/thaw cycle. * This kit is suitable for human genomic DNA library construction, the starting template DNA input amount is 1 ng, our company also has 50 ng and 5 ng of human genomic DNA starting transposase method library construction kit, in order to get a higher quality library, different starting amount of DNA is recommended to use different kits. Products IntroductionThis kit is developed for Illumina's high-throughput sequencing platform and provides the enzyme premix system and reaction buffer for genomic DNA library construction, including all components except PCR primers. Compared with the traditional library construction kits, this kit adopts the new transposase method for library construction, which can complete DNA fragmentation, end repair and junction reaction in one simple enzymatic reaction, significantly reducing the amount of template, reducing the number of experimental steps, and shortening the time of library construction; it adopts the high-fidelity DNA polymerase for library enrichment, and the preference-free PCR amplification can expand the coverage area of the sequence, which can be used for efficient and effective sequencing. The use of high-fidelity DNA polymerase for library enrichment and preference-free PCR amplification broadens the coverage area of the sequence and enables efficient preparation of DNA libraries for Illumina's second-generation sequencing platform. The kit is suitable for use with 1 ng of starting template DNA, and all reagents in the kit have been subjected to stringent quality control and functional validation to maximize the stability and reproducibility of library construction.Product Features● DNA fragmentation and junction ligation in one step.● Ultra-fidelity amplification minimizes amplification preference.Provide your own instruments, kits 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. Library PCR primer kit: It is recommended to use Kangwei transposase method for second generation sequencing multi-sample primer kit.4. Anhydrous ethanol, deionized water (pH between 7.0 and 8.0).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 Notes1. Avoid repeated freezing and thawing of reagents.2. PCR products are easily contaminated due to improper operation, resulting in inaccurate results. It is recommended to isolate the PCR reaction system preparation area from the PCR product purification area, and to use special pipettes to clean the experimental areas at regular intervals.3. Bead purification: the beads should be equilibrated to room temperature before use, all operations on the beads should be carried out at room temperature, 80% ethanol should be dispensed freshly, the beads should be rinsed and dried until the surface is free of liquid reflections and has a frosted appearance, insufficient drying of the beads will cause ethanol residue that will affect the subsequent experiments, and over-drying of the beads will affect the efficiency of DNA recovery.4. The kit is suitable for human genomic DNA library construction, if the DNA sample is a PCR product, it should be ensured that its length>.500 bp, since transposases do not work on DNA ends, it is recommended to extend the PCR product by 50-100 bp at each end of the PCR product to avoid low coverage of the ends for sequencing. Sample PreparationDNA purity requirement: A260/A280 = 1.8-2.0. Sample DNA: dissolved in ultrapure water.DNA quantification: Too much or too little DNA will affect the quality of the library. It is recommended to use Nano to test the purity of the genomic DNA and then use Qubit to test the concentration of the genome (do not use any absorbance-based assay for template quantification). Schematic diagram of DNA banking process procedureDNA fragmentation, junction reaction 1. Add the following reagents to a 200 µl PCR tube:2. Mix by gently blowing with a pipette and centrifuge briefly so that all components are collected at the bottom of the tube.3. Place the above PCR tubes in the PCR instrument with the hot cap on and program the reaction as follows:inactivation reactionAfter the DNA is fragmented, the enzyme is still in a high active state, so it should be removed from the PCR instrument immediately and terminated by adding the Reaction Termination Buffer, in order to prevent the DNA from being fragmented too much and resulting in smaller library fragments.1. Add 3 µl of TS Buffer to the PCR tube containing the fragmentation product.2. Mix by gently blowing with a pipette and centrifuge briefly so that all components are collected at the bottom of the tube.3. Incubate at room temperature for 5 min, or if the room temperature is too low, place the reaction on a PCR instrument at 25°C with the thermal cover closed.PCR amplification1. Add the following reagents to a 200 µl PCR tube.2. Mix by gently blowing with a pipette and centrifuge briefly so that all components are collected at the bottom of the tube. 3. Place the above PCR tubes in the PCR instrument with the thermal cap open, and the reaction program is as follows:Selective recovery of library DNA fragmentsIt is recommended to use CombiVision Magnetic Beads DNA Purification and Recovery Kit for selective recovery of DNA fragments. When different sizes of DNA fragments are required, the amount of magnetic beads used is different, please refer to the attached table for the specific amount of magnetic beads used.(If using other brands of magnetic beads, you need to figure out the optimal amount of magnetic beads by yourself).Note: Amplification products can also be fragment length sorted and purified using the Gum Recovery Kit. If there is no special requirement for library length distribution, amplification products can also be purified directly from DNA fragments without selective recovery of DNA fragments as described on page 4 of the manual.1. CMPure should be equilibrated at room temperature for 30 min after shaking and mixing before use.2. Transfer the PCR products to a 1.5 ml centrifuge tube, rehydrate to 100 µl, add several volumes of magnetic beads equilibrated to room temperature, vortex for 5 seconds, and let stand at room temperature for 5 minutes.3. Centrifuge briefly, place the tube on a magnetic rack to separate the beads from the supernatant until the solution is clear, and carefully aspirate the supernatant and transfer it to a new 1.5 ml centrifuge tube.Note: Do not discard the top clear.4. Add several volumes of magnetic beads to the supernatant, vortex and shake for 5 seconds, then let stand at room temperature for 5 minutes.5. Centrifuge briefly, place the tube on a magnetic rack to separate the beads from the supernatant until the solution is clear, carefully aspirate the supernatant and discard it, avoiding contact with the beads that have bound the target DNA.Note: Do not discard the beads.6. Continue to keep the centrifuge tube fixed on a magnetic rack and add 200 µl of freshly prepared 80% ethanol to the tube and allow to stand at room temperature for 30 seconds, carefully discarding the supernatant.Note: When adding ethanol, the liquid must not be blown directly onto the beads.7. Repeat step 6 once.8. Keep the centrifuge tube fixed on a magnetic rack and leave to dry at room temperature until the surface of the beads is slightly cracked, add 20 µl of ddH2O to solubilize.Note: Do not over-dry the beads as this may affect the elution efficiency.9. Remove the tube from the magnetic rack, vortex to completely resuspend the beads, and allow to stand at room temperature for 5 minutes. Centrifuge briefly, place the tube on the magnetic rack until the solution is clear, and transfer the supernatant solution to a new tube. Table: Suggested amount of magnetic beads for different segment selection recoveryLibrary DNA fragment purificationWe recommend the use of the Kangwei Century Magnetic Bead Method DNA Purification and Recovery Kit.1. CMPure should be equilibrated at room temperature for 30 min after shaking and mixing before use.2. 50 µl of magnetic beads equilibrated to room temperature were added to the PCR product, vortexed and shaken for 5 seconds, and then left to stand at room temperature for 5 minutes.3. Centrifuge briefly, place the tube on a magnetic rack to separate the beads from the supernatant solution until the solution is clear (approximately 3-5 minutes), carefully aspirate the supernatant and discard it, avoiding contact with the beads that have bound the target DNA. Note: Do not discard the beads.4. Continue to keep the centrifuge tube fixed on a magnetic rack and add 200 µl of freshly prepared 80% ethanol to the centrifuge tube and allow to stand at room temperature for 30 seconds, carefully discarding the supernatant.Note: When adding ethanol, the liquid must not be blown directly onto the beads.5. Repeat step 4.6. Keep the centrifuge tube fixed on a magnetic rack and leave to dry at room temperature until the surface of the beads is slightly cracked, add 25 µl of ddH2O to solubilize.Note: Do not over-dry the beads as this may affect the elution efficiency.7. Remove the tube from the magnetic rack, vortex to completely resuspend the beads, and allow to stand at room temperature for 5 minutes. Centrifuge briefly, place the tube on the magnetic rack until the solution is clear, and transfer the supernatant solution to a new tube. Library quality controlDetermination of library concentrationIn order to obtain high-quality sequencing results, accurate quantification of DNA libraries is required, and the first recommendation is to use Real-timePCR methods are used for absolute quantification of DNA libraries. Additionally, fluorescent dye methods such as the Qubit method or the fluorescent dye picogreen method can be used; do not use quantification methods based on absorbance measurements here. The following approximate formula can be used to convert the molar concentration of the DNA library.Library fragment distributionThe prepared DNA libraries can be detected by agarose gel electrophoresis or Agilent 2100 Bioanalyzer.Range of segment length distributions... Read More | DescriptionMetathesis: Ruthenium-Based Metathesis CatalystsRuthenium metathesis catalysts kit I consists of 9 samples of Grubbs 1st and 2nd generation catalysts. These catalysts have applications in ring-closing and ring-opening metathesis, cross-metathesis, ring-opening metathesis polymerization (DescriptionMetathesis: Ruthenium-Based Metathesis CatalystsRuthenium metathesis catalysts kit I consists of 9 samples of Grubbs 1st and 2nd generation catalysts. These catalysts have applications in ring-closing and ring-opening metathesis, cross-metathesis, ring-opening metathesis polymerization (ROMP) and enyne metathesis.Metathesis: Ruthenium-Based Metathesis Catalysts... Read More |