| Description | Product content:M665754Component25 TStorageM665754ATris-HCl, 1 mM, PH 8.01 mL-20℃. Avoid freeze/thaw cycleM665754BE. coli Poly(A) Polymerase, 5 U/µL15 µL-20℃. Avoid freeze/thaw cycleM665754C10×Poly(A) Polymerase Buffer80 µL-20℃. Avoid freeze/thaw Product content:M665754Component25 TStorageM665754ATris-HCl, 1 mM, PH 8.01 mL-20℃. Avoid freeze/thaw cycleM665754BE. coli Poly(A) Polymerase, 5 U/µL15 µL-20℃. Avoid freeze/thaw cycleM665754C10×Poly(A) Polymerase Buffer80 µL-20℃. Avoid freeze/thaw cycleM665754DATP, 10 mM15 µL-20℃. Avoid freeze/thaw cycleM665754ERT Primer, 25 µM90 µL-20℃. Avoid freeze/thaw cycleM665754F5×SuperRT Buffer120 µL-20℃. Avoid freeze/thaw cycleM665754GUltraPure dNTP Mix, 10 mM each30 µL-20℃. Avoid freeze/thaw cycleM665754HSuperRT, 200 U/µL15 µL-20℃. Avoid freeze/thaw cycleM665754IRNase-Free Water1 mL-20℃. Avoid freeze/thaw cycle Product Introduction:This kit uses the method of adding a poly (A) tail at the 3 'end of miRNA to give miRNA a Poly (A) tail, followed by reverse transcription using Oligo (dT) - Universal tag universal reverse transcription primers to synthesize the first stranded cDNA corresponding to miRNA. The miRNA cDNA first strand synthesis kit contains all the reagents required for the miRNA 3 'end Poly (A) tail modification process and the reverse transcription process after modification. This kit has a very high Poly (A) modification and reverse transcription efficiency, which can range from 1 ng-2 µ The first strand of cDNA corresponding to miRNA was effectively obtained from the total RNA of g. And the operation is simple and fast, which can be used to simultaneously detect multiple miRNAs from a synthesized cDNA reaction. This not only reduces errors and saves samples, but also achieves high-throughput detection.Note: This kit must be used in conjunction with the miRNA fluorescence quantitative detection kit.Self prepared experimental materials: 1 ng-2 µ Total RNA of g, or 0.1 ng-1 µ Small molecule RNA of g.Notes:To prevent RNase pollution, attention should be paid to the following aspects:1. Use plastic products and gun heads without RNase to avoid cross contamination.2. Glassware should be dry baked at a high temperature of 180 ℃ for 4 hours before use. Plastic containers can be soaked in 0.5 M NaOH for 10 minutes, thoroughly rinsed with water, and then sterilized under high pressure.3. The solution should be prepared using water without RNase.4. Operators should wear disposable masks and gloves, and change gloves frequently during the experiment.Usage:A. The process of miRNA adding Poly (A) tail:1.based on the amount of RNA used, dilute the total RNA of 10 mM ATP with 1 mM Tris (pH 8.0) according to the following formula: ATP dilution coefficient=5000/__ ngExample: If the initial amount of total RNA is 100 ng, then the ATP dilution coefficient is 5000/100=50. About to dilute ATP 50 times (1 µ 10 mM ATP plus 49 for l µ 1 mM Tris at pH 8.0.2. Add the following reagents to the pre cooled RNase free reaction tube in the ice bath to a total volume of 25 µ L. reagent 25 µlReaction system final concentration total RNA* X µl Up to 2 µg 10×Poly(A) Polymerase Buffer 2.5 µl 1× Diluted ATP in step "1" 1 µl / E. coli Poly(A) Polymerase, 5U/µl 0.5 µl 2.5 U RNase-Free Water up to 25 µl /*The total RNA used in the reaction must contain small molecule RNA.This process can also directly use small molecule RNA (recommended dosage of 2-5) µ L. Please determine the amount added based on the abundance of the target miRNA.3. Gently mix the above reaction solution and briefly centrifuge to collect the liquid at the bottom of the tube. Incubate at 37 ℃ for 15 minutes. After this process is completed, immediately proceed with the synthesis of the first strand cDNA or temporarily store it at -20 ℃. If long-term storage is required, it is recommended to store at -80 ℃.B. The process of synthesizing the first strand of modified miRNA cDNA:1. Add the reagents in the table below to the pre cooled RNase free reaction tube in the ice bath until the final volume reaches 20µl: reagent 20 µlReaction system The above Poly (A) reaction solution 4 µl UltraPure dNTP Mix ，10 mM each 1 µl RT Primer ，25 µM 3 µl 5×SuperRT Buffer 4 µl SuperRT ，200 U/µl 0.5 µl RNase-Free Water 7.5 µl2. Gently mix the above reaction solution and briefly centrifuge to collect the liquid at the bottom of the tube. Incubate at 42 ℃ for 50 minutes.3.85 ℃ for 5 minutes and terminate the reaction. The synthesized cDNA reaction solution can be directly used for fluorescence quantitative detection experiments or stored at -20 ℃ for future use... Read More | Product content:E665636Component50 TStorageE665636ABuffer P115 mLRTE665636BBuffer P215 mLRTE665636CBuffer E315 mLRTE665636DBuffer PS15 mLRTE665636EBuffer PW (concentrate)10 mLRTE665636FEndo-Free Buffer EB10 mLRTE665636GRNase A (10 mg/mL)150 µLRTE665636HEndo-Remover FMwith Collection Tubes50 Product content:E665636Component50 TStorageE665636ABuffer P115 mLRTE665636BBuffer P215 mLRTE665636CBuffer E315 mLRTE665636DBuffer PS15 mLRTE665636EBuffer PW (concentrate)10 mLRTE665636FEndo-Free Buffer EB10 mLRTE665636GRNase A (10 mg/mL)150 µLRTE665636HEndo-Remover FMwith Collection Tubes50 EARTE665636ISpin Columns DMwith Collection Tubes50 EART Product Introduction:Endotoxins are a common pollutant in plasmid extraction. Due to the high sensitivity of eukaryotic cells to endotoxins, the presence of endotoxins in plasmids can greatly reduce the transfection efficiency of eukaryotic cells. This reagent kit provides a simple, fast, and efficient new method for extracting endotoxin free plasmids. The extracted plasmids remove endotoxins to the maximum extent possible and can effectively remove contamination of genomic DNA, RNA, proteins, etc. The operation is simple and convenient. This reagent kit is suitable for extracting 1-5mL of bacterial solution. On the basis of alkaline lysis of cells, it efficiently and specifically binds plasmid DNA through a new silicon-based membrane. Each adsorption column can adsorb up to 40% µ The plasmid DNA of g is effectively removed using a special buffer system and endotoxin removal filter column, effectively removing impurities such as endotoxins and proteins. The plasmid obtained from this kit has high purity and stable quality, making it particularly suitable for cell transfection. It can also be used for downstream experiments such as DNA sequencing, PCR, PCR based mutations, in vitro transcription, transformed bacteria, and endonuclease digestion.Self prepared reagents: anhydrous ethanol, isopropanol.Preparation and important precautions before the experiment：1. All components can be stably stored for 1 year in a dry, room temperature (15-30 ℃) environment. The adsorption column can be stored for a longer time at 2-8 ℃. Buffer P1 with RNase A added can be stably stored for 6 months at 2-8 ℃. 2. Before the first use, add all RNase A solution to Buffer P1, mix well, and store at 2-8 ℃. Before use, let it sit at room temperature for a period of time. After returning to room temperature, use.3.Before the first use, anhydrous ethanol should be added to the Buffer PW according to the instructions on the reagent bottle label.4. Before use, please check if there is any crystallization or precipitation in Buffer P2 and Buffer E3. If there is any crystallization or precipitation, you can take a water bath at 37 ℃ for a few minutes to restore clarity.5. Be careful not to come into direct contact with Buffer P2 and Buffer E3, and immediately cover them tightly after use.6.The amount and purity of plasmid extraction are related to factors such as bacterial culture concentration, strain type, plasmid size, and plasmid copy number.Operation steps：1. Take 1-5 mL of overnight cultured bacterial solution and add it to a centrifuge tube (provided). Centrifuge at 13000 rpm (~16200 × g) for 30 seconds to collect bacteria, and try to discard all the supernatant as much as possible.2. Add 250 to the centrifuge tube containing bacterial sediment µ L Buffer P1 (please check if RNase A has been added first), mix thoroughly with a pipette or vortex oscillator, and suspend bacterial precipitation.Attention: If the bacterial blocks are not thoroughly mixed, it will affect the cracking effect, resulting in low extraction amount and purity.3. Add 250 to the centrifuge tube µ L Buffer P2, gently invert and mix 8-10 times, allowing the bacterial cells to fully lyse. Leave at room temperature for 3-5 minutes. At this point, the solution should become clear and viscous.Attention: Mix gently and do not shake vigorously to avoid interrupting genomic DNA and mixing genomic DNA fragments in the extracted plasmid. If the solution does not become clear, it indicates that the bacterial count may be too high and the lysis may not be complete. The bacterial count should be reduced.4. Add 250 to the centrifuge tube µ L Buffer E3, immediately invert and mix 8-10 times until white flocculent precipitates appear. Let it stand at room temperature for 5 minutes. Centrifuge at 13000 rpm for 5 minutes, extract the supernatant, and add it to a filter column (Endo Remove FM). Centrifuge at 13000 rpm for 1 minute to filter, and collect the filtrate in a centrifuge tube (self provided).Attention: After adding Buffer E3, it should be mixed evenly immediately to avoid local precipitation. 5. Add 225 to the filtrate µ Mix L isopropanol upside down.6. Column balance: Add 200 to the spin columns DM that have been loaded into the collection tube µ L Buffer PS, centrifuge at 13000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.7. Transfer the mixed solution of filtrate and isopropanol from step 5 to an equilibrium adsorption column (already loaded into a collection tube).8.13000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.Attention: The maximum volume of the adsorption column is 750 µ L. If the sample volume is greater than 750 µ L can be added in batches. 9. Add 750 to the adsorption column µ L Buffer PW (please check if anhydrous ethanol has been added first), centrifuge at 13000 rpm for 1 minute, and discard the waste liquid in the collection tube.10. Place the adsorption column back into the recovery manifold and centrifuge at 13000 rpm for 1 minute. Note: The purpose of this step is to remove residual ethanol from the adsorption column, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).11. Place the adsorption column in a new collection tube and add 50-100 to the middle of the adsorption membrane µ L Endo Free Buffer EB, let it stand at room temperature for 2-5 minutes, centrifuge at 13000 rpm for 2 minutes, and collect the plasmid solution into a centrifuge tube- Store the plasmid at 20 ℃.Note: 1) To increase the efficiency of plasmid recovery, the obtained solution can be added back to the adsorption column, left at room temperature for 2-5 minutes, centrifuged at 13000 rpm for 2 minutes, and collected into a centrifuge tube.2) When the plasmid copy number is low or>10 kb, preheating the Endo Free Buffer EB in a water bath at 65-70 ℃ can increase the extraction efficiency... Read More | Live & deadtm animal cell viability / toxicity detection kit (calcein am, ethd-i) is a kit that provides double fluorescent staining for the detection of animal cell death and survival. The two probes in the kit can respectively measure the activity of cellular lactonase and the integrity of Live & deadtm animal cell viability / toxicity detection kit (calcein am, ethd-i) is a kit that provides double fluorescent staining for the detection of animal cell death and survival. The two probes in the kit can respectively measure the activity of cellular lactonase and the integrity of plasma membrane to reflect cell viability. The kit can be used for fluorescence microscopy, flow cytometry, microplate reader and other fluorescence detection systems. This kit can be applied to most eukarYOtic mammalian cells, including some tissues with adherent nuclei, but it is not applicable to fungi and yeast. Compared with trypan blue, the kit is faster, safer and more sensitive.Component： Product parameters：Calcein am: ex/em = 494 / 517 nm; Ethd-i: ex/em = 528 / 617 nm (bound DNA)Usage:Fluorescence microscopy detection1. Prepare working fluidPreparation 2 µ M Calcein AM and 4 µ M EthD-I staining solution: Remove the original solution of Calcein AM and EthD-I and restore them to room temperature. Add 20 µ L 2 mM EthD-I and 5 µ Mix 4 mM Calcein AM with 10 mL PBS or other serum-free buffer or culture medium, vortex well. The above working solution can be directly used for cell staining.Note: The aqueous solution of Calcein AM is easily hydrolyzed and should be used up every day. The concentration selection of Calcein AM and EthD-I varies depending on the type of cell used, with a recommended concentration range of 0.1-10 µ M.2. Prepare cells and conduct experiments(1) For adherent cells, they can be washed 2-3 times with 1 × PBS before staining. For suspended cells, centrifuge at room temperature of 250-1000 × g for 5 minutes and collect cells for staining.(2) Wash the cells thoroughly 2-3 times with 1 × PBS to remove residual esterase activity.(3) For adherent cells, add sufficient amount of Calcein AM/EthD-I staining solution. For suspended cells, add an appropriate amount of staining solution to control the cell density between 1-5 × 105/mL.(4) Incubate at room temperature in dark for 15-20 minutes (if the working solution concentration is high or the incubation temperature is high, the incubation time should be appropriately reduced).(5) Observe the labeled cells under a fluorescence microscope.Flow cytometry detection1. Remove the reagent and restore it to room temperature.2. Preparation 2 µ M Calcein AM and 4 µ M EthD-I staining solution: Take out the original solution of Calcein AM and EthD-I, and restore to room temperature. Add 20 µ L 2 mMEthD-I and 5 µ Vortex mix 4 mM Calcein AM with 10 mL PBS or other serum-free buffer or culture medium. The working fluid can directly stain cells.3. Wash cells thoroughly 2-3 times with 1 × PBS.4. Suspend cells with 0.5 mL of staining solution and control the cell density to 1-5 × 105/mL.Note: It is recommended to prepare two additional cell samples, each containing only one dye (Calcein AM and EthD-I), for compensatory regulation of flow cytometry single staining; Prepare another cell sample containing only buffer solution (which should be consistent with the buffer used to prepare Calcein AM and EthD-I detection working solutions) as a negative control for flow cytometry analysis.5. Incubate at room temperature in dark for 15-20 minutes.6. Within 1-2 hours, cell activity was detected by flow cytometry. Calcein AM can be excited by a 488 nm laser, with fluorescence emission spectra detected at around 530 nm and EthD-I emission spectra at around 610 nm.Note: When using the cell circle gate, attention should be paid to excluding cell debris and using a single staining tube to regulate compensation. Double staining tube flow cytometry should obtain two relatively independent cell populations: a live cell population displaying green fluorescence and a dead cell population displaying red fluorescence.ELISA reader detection1. Cultivate an appropriate amount of adherent or suspended cells in a 96 well black ELISA plate.Note: Dead cells can be obtained by treating cells with 1% saponin or 0.1-0.5% digitalis saponin for 10 minutes.2. Preparation 2 µ M Calcein AM and 4 µ M EthD-I staining solution:Remove the original solutions of Calcein AM and EthD-I and restore them to room temperature. Add 20 µ L 2 mM EthD-I and 5 µ Mix 4 mM Calcein AM 10 mL PBS or other serum-free buffer or culture medium, vortex well.Note: (1) 10 mL of staining solution is sufficient to stain a 96 well plate, and the volume of the staining solution can be adjusted according to experimental needs. The concentrations of Calcein AM and EthD-I can range from 0.1 to 10 µ Explore between M.(2) The aqueous solution of Calcein AM is easily hydrolyzed and should be used up every day. EthD-I working solution can be stored at -20 ℃ for at least one year.3. Wash the cells thoroughly with 1 × PBS to remove residual esterase activity. For adherent cells, add 100 to each well µ Wash cells with PBS. For suspended cells, add 100 µ Resuspend cells with L PBS and centrifuge to remove the supernatant. Repeat the above operation.4. Add 100 to each hole µ L PBS.5. Add 100 to each hole µ L staining solution, making the total volume of each well 200 µ L. The final concentration of Calcein AM is 1 µ M. The final concentration of EthD-I is 2 µ M. Gently shake the culture plate to evenly cover the cells with the liquid.Incubate at room temperature in dark for 30-45 minutes.Note: The optimal incubation time varies for different cells, with 30 minutes as the initial incubation time. Subsequently, the staining time can be adjusted and optimized according to the actual staining effect to obtain a more ideal staining effect.7. Enzyme reader detection. When the ELISA reader is set to fluorescein, it can detect Calcein AM; When the ELISA reader is set to rhodamine or Texas Red, EthD-I can be detected. Select the optimal emission and excitation wavelengths based on spectral characteristics.Note: By comparing the relative fluorescence values (RFU) measured between the sample group and the control group, the changes in the number of dead and live cells can be obtained. Another method of data analysis is also provided below.The following method can calculate the ratio of live cells to dead cells in a certain region. The required samples include dead cell control group, live cell control group, and the sample group to be tested. Dead cells can be obtained by treating cells with 1% saponin or 0.1-0.5% digitalis saponin for 10 minutes.1. Prepare staining solution and follow the above steps to stain cells. Additionally, prepare 1 mL and 2 mL separately µ M Calcein AM and 4 µ M EthD-I solution, stain the control group according to the following instructions. For the following groups of cells or cell-free groups, it is necessary to maintain complete consistency in cell count, detection of working solution concentration, incubation time, and incubation temperature.2. Measurement of sample group and control group:A. The measured values of the sample group at 645 nm are denoted as Calcein AM and EthD-I=F (645) sam.B. The measured values of the sample group at 530 nm are denoted as Calcein AM and EthD-I=F (530) sam.C. The measurement value of dead cell EthD-I single staining control group at 645 nm is denoted as EthD-I=F (645) maxD. The measurement value of dead cell Calcein AM single staining control group at 645 nm is recorded as Calcein AM=F (645) minE. The measurement value of live cell EthD-I single staining control group at 530 nm is recorded as EthD-I=F (530) min.F. The measurement value of live cell Calcein AM single staining control group at 530 nm is denoted as Calcein AM=F (530) max.G. A blank control well without cells (with or without dye), the detection value at 530 nm is recorded as F (530) 0.H. A blank control well without cells (with or without dye), the detection value at 645 nm is recorded as F (645) 0.3. Calculate the ratio of dead cells to live cells based on measurement data:%Live Cells=(B-E) ÷ (F-E)%Dead Cells=(A-D) ÷ (C-D)Determine the ratio of live cells to dead cells in a certain areaBy creating fluorescence spectral standard curves at 530 nm and 645 nm, the number of dead and live cells can be determined, and the fluorescence intensity of each dye is linearly related to the number of dead or live cells in the sample.Matters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. phenol red or serum may interfere with the detection of this kit. 3. fluorescent dyes have quenching problems. Please try to avoid light during experimental operation to slow down fluorescence quenching. 4. for your safety and health, please wear experimental clothes and disposable gloves.Scope of application：Dead and live cell staining (animal)... Read More | Products contentN669983Component240 TStorageN669983AIndex N501 Primers for Illumina240 µL-20℃. Avoid freeze/thaw cycle.N669983BIndex N973-N996 Primers for Illumina24×10 µL-20℃. Avoid freeze/thaw cycle. Products IntroductionThis kit is a companion kit to the transposase-Products contentN669983Component240 TStorageN669983AIndex N501 Primers for Illumina240 µL-20℃. Avoid freeze/thaw cycle.N669983BIndex N973-N996 Primers for Illumina24×10 µL-20℃. Avoid freeze/thaw cycle. 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 DNA purification and recovery kit by magnetic bead method.3. DNA building kit: It is recommended to use the 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 | 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 |