| Description | Free Fatty Acids (FFA), also known as Non-Esterified Fatty Acids (NEFA), are primarily produced by the hydrolysis of neutral fats. They are intermediate products in fat metabolism, involved in cell proliferation, inflammatory responses, and hormone regulation. FFA can also act as signaling moleculesFree Fatty Acids (FFA), also known as Non-Esterified Fatty Acids (NEFA), are primarily produced by the hydrolysis of neutral fats. They are intermediate products in fat metabolism, involved in cell proliferation, inflammatory responses, and hormone regulation. FFA can also act as signaling molecules with various physiological functions. Free fatty acids are closely related to lipid metabolism, glucose metabolism, and endocrine function. Their concentration is an important physiological and biochemical indicator, serving as an auxiliary parameter for disease evaluation and diagnosis, and also reflecting quality changes during food storage.Detection Principle: FFAs combine with copper ions to form copper soaps, which are soluble in chloroform. The copper ions can then react with a chromogenic solution to form a purplish-red complex. This product has a characteristic absorption peak at 550 nm. The FFA content can be quantified by measuring the change in absorbance.Detection Range: 0.0313 - 2 mMSensitivity: 0.0156 mMApplicable Samples: Serum (plasma), animal/plant tissues, cells, bacteria.A1492746Component48T96TStorageA1492746ACu Reagent6 mL12 mL2-8℃. Store in the dark.A1492746BChromogen15 mL30 mL2-8℃. Store in the dark.A1492746CStandard (16.41 mg Palmitic Acid)1 EA1 EA2-8℃. Store in the dark.User-Prepared Instruments and ReagentsMicroplate reader or visible spectrophotometer (capable of measuring absorbance at 550 nm)Incubator, Ice maker, Low-temperature centrifuge96-well plate or micro glass cuvettes, Adjustable pipettes and tipsHomogenizer (for tissue samples)Glass bottle (for preparing extraction buffer)n-Heptane, Anhydrous methanol, ChloroformExperimental Procedure1. Reagent PreparationReagent NameReagent PreparationPrecautionsExtraction Buffer (Self-prepared)In a glass bottle, mix Chloroform : n-Heptane : Anhydrous Methanol = 28 : 21 : 1. Cap tightly and mix well.Store at 4°C protected from light.Cu ReagentReady-to-use; equilibrate to room temperature before use; mix well before use.Store at 4°C protected from light.ChromogenReady-to-use; equilibrate to room temperature before use.Store at 4°C protected from light.StandardBefore use, dissolve contents in 1 mL of Extraction Buffer to obtain a 64 mM Standard solution. Mix well.Unused dissolved Standard can be stored in a tightly sealed glass bottle at 4°C protected from light for 1 month.2. Standard Curve SetupDilute the 64 mM Standard further with Extraction Buffer as shown in the table below.Standard No.Standard (µL)Extraction Buffer Volume (µL)Standard Concentration (mM)Std.120µL of 64mM stock6202Std.2100µL of Std.11001Std.3100µL of Std.21000.5Std.4100µL of Std.31000.25Std.5100µL of Std.41000.125Std.6100µL of Std.51000.0625Std.7100µL of Std.61000.0313Note: Prepare freshly diluted standards for each experiment.3. Sample PreparationNote: Fresh samples are recommended. If not used immediately, samples can be stored at -80°C for up to 6 months.3.1 Animal Tissues: Weigh approximately 0.1 g of tissue, add 1 mL of Extraction Buffer, and homogenize on ice. Centrifuge at 8,000 rpm, 4°C for 10 min. Collect the supernatant and keep on ice for detection.3.2 Plant Tissues: Weigh approximately 0.1 g of tissue, add 1 mL of Extraction Buffer, and grind. Disrupt by ultrasonic homogenization on ice (power 20% or 200 W, ultrasonicate for 3 s, interval 7 s, repeat 30 times). Centrifuge at 8,000 rpm, 4°C for 10 min. Collect the supernatant and keep on ice for detection.3.3 Cells or Bacteria: Collect 5 million cells or bacteria into a centrifuge tube. Wash with cold PBS, centrifuge, and discard the supernatant. Add 1 mL of Extraction Buffer. Disrupt by ultrasonic homogenization on ice (power 20% or 200 W, ultrasonicate for 3 s, interval 7 s, repeat 30 times). Centrifuge at 8,000 rpm, 4°C for 10 min. Collect the supernatant and keep on ice for detection.3.4 Serum (Plasma) and other liquids: Detect directly.4. Assay Steps4.1 Instrument Preparation: Preheat the microplate reader or visible spectrophotometer for at least 30 minutes. Set the wavelength to 550 nm. For spectrophotometers, zero the instrument with deionized water.4.2 Sample Assay (Add reagents sequentially to EP tubes):ReagentBlank Tube (µL)Standard Tube (µL)Test Tube (µL)Extraction Buffer240200200Various Std.0400Sample0040Cap the tubes tightly and vortex at medium speed for 30 seconds.Cu Reagent808080Cap the tubes tightly and vortex at medium speed for 30 seconds. Incubate at room temperature (25°C) for 20 minutes. Centrifuge at 2,000 g, room temperature (25°C) for 5 minutes.Upper Phase505050Chromogen2002002004.3 Incubate at room temperature (25°C) for 5 minutes. Transfer 200 µL from each tube to the corresponding wells of a 96-well plate or micro glass cuvettes. Measure the absorbance at 550 nm.Calculate ΔAtest=Atest-Ablank and ΔAstd=Astd-Ablank (The blank tube only needs to be set up once).Note: The measurement must be completed within 30 minutes after color development. It is recommended to perform preliminary experiments with 2-3 samples expected to have significant differences before formal testing. If Atest exceeds the detection range of the instrument, dilute the sample further with Extraction Buffer and multiply the result by the dilution factor.5. Result CalculationWe provide both derived and simplified calculation formulas, which are equivalent. The simplified formulas in bold are recommended as the final calculation formulas.5.1 Standard Curve PlottingPlot the standard curve with standard concentration as the y-axis and ΔAstd as the x-axis (using concentration as the y-axis facilitates calculation). Substitute ΔAtest into the standard curve equation to obtain y (mM).5.2 Sample FFA Content Calculation(1) Based on sample mass:FFA Content (µmol/g fresh weight) = y × Vextract ÷ W × n = y ÷ W × n(2) Based on bacterial or cell count:FFA Content (µmol/10⁴ cells) = y ÷ (Cell or Bacterial Count ÷ Vextract ) × n = y ÷ 500 × n = 0.002 × y × n(3) Based on liquid volume:FFA Content (µmol/L) = 1000 × y × nParameter Description:Vextract : Volume of Extraction Buffer added, 1 mLW: Sample mass, gn: Sample dilution factor (if further diluted)500: Cell or bacterial count, in units of 10⁴1000: Unit conversion factor, 1 L = 1000 mL6. Result PresentationTypical Standard Curve: y = 0.679x - 0.0109, R² = 0.9988(Free Fatty Acid (FFA) standard curve analyzed using a 96-well plate. Data and curve are for reference only; users must establish their own standard curve based on their experiment.)Precautions1. Biochemical reagents are generally irritating and biologically toxic. For your safety and health, please implement appropriate biosafety precautions throughout the experiment. Wear personal protective equipment such as lab coats, masks, gloves, and hair caps. Perform experiments in a fume hood or biosafety cabinet.2. This product is for scientific research use only. Not intended for clinical diagnosis... Read More | Calcein AM /PI Double Staining Kitis utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stains viable and dead cells, respectively(Fig. 1). Calcein-AM, an acetoxymethyl ester of calcein, is highly Calcein AM /PI Double Staining Kitis utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stains viable and dead cells, respectively(Fig. 1). Calcein-AM, an acetoxymethyl ester of calcein, is highly lipophilic and cell membrane permeable. Though Calcein-AM itself is not a fluorescent molecule, the calcein generated from Calcein-AM by esterase in a viable cell emits a strong green fluorescence (excitationat 490 nm, emission at515 nm). Therefore, Calcein-AM only stains viable cells. On the other hand, PI, a nuclei staining dye, cannot pass through a viable cell membrane. It reaches the nucleus by passing through disordered areas of dead cell membrane, and intercalates with the DNA double helix of the cell to emit red fluorescence (excitation: 535 nm,emmision: 617 nm). Since both calcein and PI-DNA can be excited with 490 nm, simultaneous monitoring of viable and dead cells is possible with a fluorescence microscope. With 545 nm excitation, only dead cells can be observed (Fig. 1). Since optimal staining conditions differ from cell line to cell line, we recommend that a suitable concentration of PI and Calcein-AM be individually determined. Please note that PI is suspected to be highly carcinogenic;careful handling is required.Required Equipment and Materials:Microscope with 490 nm excitation filter and 530 nm emission filter；CO2incubator；10 µl and 200 µl adjustable pipettes, PBSSolution A (Calcein-AM)；Solution B (PI) Storage Condition: -20oC ；Shipping Condition: blue ice.Application:Assay Procedure1)Add 2.5 µl Solution A and 12.5 µl Solution B to 5 ml PBS to prepare assay solution.*2)Wash the cell with PBS several times to remove residual esterase activity.3)Add 100uLof assay solution to200uL105~106CELLSsolution and incubate the mixture at 37oC for 15 min.4)Detect fluorescence using a fluorescence mircoscope with 490 nm excitationfor simultaneous monitoring of viable and dead cells.With 545 nm excitation, only dead cells can be observed.*The following steps may be necessary tooptimizethe suitable concentration of each reagent:1)Prepare dead cells by 10 min incubation in 0.1% saponin or 0.1-0.5% digitonin or by 30 min incubation in 70% ethanol.2)Stain dead cells with 0.1-10 µM PI solution to find a PI concentration that stains the nucleus only, not the cytosol.3)Stain dead cells with 0.1-10 µM Calcein-AM solution to find a Calcein-AM concentration that does not stain the cytosol. Then stainviable cells with that Calcein-AM solution to check whether the viable cell can be stained... Read More | N665917 Component 1 mL 5 mL Storage N665917A 2×SYBR qPCR MasterMix 1 mL 5×1 mL -20℃. Avoid freeze/ Thaw cycle. N665917B qPCR Primer Mix 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665917C DNA Standard A 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665917 Component 1 mL 5 mL Storage N665917A 2×SYBR qPCR MasterMix 1 mL 5×1 mL -20℃. Avoid freeze/ Thaw cycle. N665917B qPCR Primer Mix 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665917C DNA Standard A 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665917D DNA Standard B 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665917E DNA Standard C 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665917F DNA Standard D 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665917G DNA Standard E 100 µL 500 µL -20℃. Avoid freeze/ Thaw cycle. N665917H 50×High ROX 40 µL 200 µL -20℃. Avoid freeze/ Thaw cycle.Product IntroductionThis is a dye-based (SYBR Green I) qPCR NGS library quantification kit for cfDNA, which provides the reaction mixture, DNA primer mixture, standards, and sample dilutions required for the qPCR process, making it a complete reagent system that is easy and convenient to use. The fluorescent dye SYBR Green I contained in the reaction mixture binds to all double-stranded DNA. The kit uses a new chemically modified high-efficiency hot-start polymerase, the activation of the enzyme needs to be incubated at 95 ℃ for 10 min. the product is highly specific, high amplification efficiency, the length of the standard in the kit (about 270bp) is comparable to the average length of the cfDNA NGS libraries (250-300bp), which is able to quickly and accurately quantitate the concentration of the constructed cfDNA libraries. quantification.ROX dye is used to correct the fluorescence signal error generated between wells of a quantitative PCR instrument, and is generally used in Real Time PCR amplifiers from ABI, Stratagene, and other companies. The excitation optics vary from instrument to instrument, so the concentration of ROX dye must be matched to the corresponding fluorescence quantitative PCR instrument.Instruments that do not require ROX calibration: Roche LightCycler 480, Roche LightCyler 96, Bio-rad iCyler iQ, iQ5, CFX96, etc.Instruments requiring Low ROX calibration: ABI Prism7500/7500 Fast, QuantStudio®3 System, QuantStudio®5 System, QuantStudio®6 Flex System, QuantStudio®7 Flex System, ViiA7 System, Stratagene Mx3000/Mx3005P, Corbett Rotor Gene 3000, and others.Instruments requiring High ROX calibration: ABI Prism7000/7300/7700/7900, Eppendorf, ABI Step One/Step One Plus, etc.NOTE: High Rox and Low Rox are formulated as described in Method of Use 2.Applicable scopeThis product is designed for the absolute quantification of the concentration of Illumina platform second generation sequencing libraries. The end of the library contains Illumina P5 and P7 microarray binding sequences, the length of which does not exceed 1kb, and the concentration is not less than 0.02pM can be used for quantitative experiments. The qPCR Primer Mix provided in the kit contains the following two primer sequences:Primer 1:5'-AAT GAT ACG GCG ACC ACC GA-3' Primer 2: 5'-CAA GCA GAA GAC GGC ATA CGA-3'The primer sequence can be used in advance to confirm whether the library can be amplified by that primer pair.UsageAmplification template preparationThe library samples to be detected were diluted with TE (10 mM Tris-Cl, pH 8.0, 1 mM EDTA), and the concentration after dilution was as close as possible to the range of 0.01-60 pM. 4°C on ice was set aside.qPCR reaction system preparationThe desired cryopreservation reagent is pre-melted completely and mixed by inverting several times before preparation, then centrifuged briefly and set aside.The base reaction system for 20 µl was as follows:Reagent20 µl Reaction system2×SYBR qPCR MasterMix10 µlqPCR Primer Mix0.8 µlTemplate4 µlddH₂O5.2 µlDescription: High Rox model: 1 µl High Rox per 50 µl of reaction system; Low Rox model: 1 µl High Rox per 500 µl of reaction system.Prepare a sufficient amount of reaction system mixture according to the need, mix well and add to the reaction wells in a volume of 16 µl per well, add the same volume of TE to the blank control, and then add the prepared standards and diluted samples to the corresponding reaction wells in a volume of 4 µl/well. It is recommended to use 20 µl reaction system, if you need to carry out a smaller system reaction, the system components can be reduced in equal proportion.3.qPCR reaction programIf the average length of the library is greater than 700bp, the annealing/extension time should be increased appropriately.Refer to the specific instrument setup program for dissolution curves.data analysisStandard curve productionThe standard curve was plotted according to the data processing Excel sheet. The correlation coefficient R2 of the standard curve should be not less than 0.99, and the slope should be located between -3.1 and -3.6 when the Ct value is the longitudinal coordinate. If the parameters of the standard curve are unreasonable, it is recommended to repeat the experiment.DNA Standard NameDNA Standard ConcentrationDNA Standard A60 pMDNA Standard B6 pMDNA Standard C0.6 pMDNA Standard D0.06 pMDNA Standard E0.006 pMLibrary Concentration CalculationsThe difference in Ct between the three replicate wells of the experiment should be no more than 0.2, otherwise the invalid data should be deleted or the experiment should be repeated. Do not use the Ct outside the valid Ct range of the standard curve to calculate the concentration of the diluted libraries. Please refer to the data processing Excel of this product for the specific library concentration calculation method.matters needing attentionThese instructions should be read in detail before testing. It should be carried out by personnel with specialized experience or qualified by training.Mix gently by turning up and down, avoid foaming as much as possible, and centrifuge for a short time before use.Avoid repeated freezing and thawing of this product; repeated freezing and thawing may degrade product performance.When preparing reaction solutions, use new or non-contaminated tips and centrifuge tubes to prevent contamination as much as possible... Read More | Q665720 Component 200T Storage Q665720A Buffer L2 25 mL RT Q665720B Buffer N3 80 mL RT Q665720C Buffer PB 35 mL RT Q665720D Buffer PW (concentrate) 25 mL RT Q665720E Buffer EB 30 mL RT Q665720F RNase A (10 mg/mL) 800 渭L RT Q665720G Spin Columns DM with Collection Tubes 200 EA RTProduct Q665720 Component 200T Storage Q665720A Buffer L2 25 mL RT Q665720B Buffer N3 80 mL RT Q665720C Buffer PB 35 mL RT Q665720D Buffer PW (concentrate) 25 mL RT Q665720E Buffer EB 30 mL RT Q665720F RNase A (10 mg/mL) 800 渭L RT Q665720G Spin Columns DM with Collection Tubes 200 EA RTProduct IntroductionThe biggest feature of this kit: simple and fast, high extraction volume. The whole extraction process does not take more than 10 minutes, without centrifugation to collect bacteria and resuspend the bacterium, directly add the unique super lysate Buffer L2 to the cultured bacterial solution, followed by neutralization, centrifugation and passing through the column, and the extracted plasmid can be as high as 30 µg, and maximize the removal of proteins, genomes and other impurities. The extracted plasmid DNA can be directly used for bacterial transformation, digestion, PCR, in vitro transcription, sequencing and other downstream experiments.Self-contained reagent: anhydrous ethanol.Pre-experiment Preparation and Important Notes1. The kit can be stored in a dry, room temperature (15-30°C) environment for 1 year. For longer storage, the centrifuge columns can be placed at 2-8°C.2. Before the first use, add all of the RNase A solution to Buffer N3, mix well, and store at 2-8°C.3. Anhydrous ethanol should be added to Buffer PW before the first use according to the instructions on the reagent bottle label.4. If there is any precipitation in Buffer L2 before use, please put it in a 37℃ water bath and keep mixing until the solution becomes clear before use.Operation steps1. Take 600 µl of bacterial culture into a 1.5 ml centrifuge tube (supplied).2. Add 100 µl of Buffer L2 to the above centrifuge tube and gently turn the solution up and down 8 times; the solution should change from turbid to a clear purple color, indicating complete lysis. The cleavage time should not exceed 2 minutes.3. Add 350 µl of Buffer N3 to the above centrifuge tube (please check that RNaseA has been added first) and immediately mix well by turning up and down about 8-10 times, at which point the solution should turn completely yellow and a yellow precipitate should form. centrifuge at 13,000 rpm for 2-3 minutes.4. Slowly pour the supernatant obtained in step 3 into the prepared adsorption columns (Spin Columns DM with Collection Tubes) to avoid sedimentation into the columns.5. Centrifuge at 13,000 rpm for 15 seconds, pour off the waste liquid in the collection tube, and put the adsorption column back into the collection tube.6. Add 150 µl Buffer PB to the adsorption column and centrifuge at 13,000 rpm for 15 seconds.7. Add 400 µl Buffer PW to the adsorption column (please check that anhydrous ethanol has been added first) and centrifuge at 13,000 rpm for 1 minute.8. Place the adsorbent column in a new centrifuge tube (self-provided), add 30-100 µl Buffer EB to the middle part of the adsorbent membrane, centrifuge at 13,000 rpm for 1 min, collect the plasmid DNA, and store at -20°C for long term storage.When the amount of extracted bacterial liquid is >600µl, the following procedure can be used:1. This kit can extract up to 3ml of bacterial solution, if the amount of extracted bacterial solution is more than 600µl, it is necessary to centrifuge the bacterial solution exceeding 600µl at 13,000rpm for 30 seconds (to collect the bacterial body), discard the supernatant and then add 600µl of bacterial solution, and then resuspend the bacterial body at the bottom of the tube thoroughly and then proceed to the following operation.2. Add 100µl Buffer L2 to the above centrifuge tube, gently invert the solution up and down 10 times, if the solution is not clarified, need to continue to invert the mixing until the solution becomes a clear purple color, the lysis time should not be more than 2 minutes. (If the solution is still turbid, the amount of bacteria is too large, and the amount of bacteria should be reduced appropriately.)3. Add 350 µl of Buffer N3 to the above centrifuge tube (please check that RNaseA has been added first) and immediately mix well by turning up and down until the purple solution turns completely yellow and a yellow precipitate is formed before proceeding to the next step. centrifuge at 13,000 rpm for 5 minutes.4. Transfer the supernatant to a new centrifuge tube, add 200 µl of isopropanol, mix up and down several times, mix well and transfer to the adsorbent column (Spin Columns DM with Collection Tubes), due to the amount of solution is too large, this time, it is necessary to centrifuge the column in two separate times, centrifugation at 13,000 rpm for 15 seconds, pour off the waste liquid in the collection tube, and put the adsorbent column back to the The adsorbent column should be placed back into the collection tube.5. Add 150 µl Buffer PB to the adsorption column and centrifuge at 13,000 rpm for 15 seconds.6. Add 400 µl Buffer PW to the adsorption column (please check that anhydrous ethanol has been added first) and centrifuge at 13,000 rpm for 1 minute.7. Place the adsorbent column in a new centrifuge tube (self-provided), add 50-200 µl Buffer EB to the middle part of the adsorbent membrane, leave it at room temperature for 2 min, centrifuge at 13,000 rpm for 1 min, collect the plasmid DNA, and store it at -20°C for a long time... Read More | Product contentY666144Component50 TStorageY666144ABuffer P115 mLRTY666144BBuffer P215 mLRTY666144CBuffer N320 mLRTY666144DBuffer PS15 mLRTY666144EBuffer PB10 mLRTY666144FBuffer PW (concentrate)10 mLRTY666144GBuffer EB10 mLRTY666144HGlass Beads2 gRTY666144IRNase A (10mg/mL)150 µLRTY666144JSpin Product contentY666144Component50 TStorageY666144ABuffer P115 mLRTY666144BBuffer P215 mLRTY666144CBuffer N320 mLRTY666144DBuffer PS15 mLRTY666144EBuffer PB10 mLRTY666144FBuffer PW (concentrate)10 mLRTY666144GBuffer EB10 mLRTY666144HGlass Beads2 gRTY666144IRNase A (10mg/mL)150 µLRTY666144JSpin Columns DM with Collection Tubes50 setsRTProductsThis kit is improved on the basis of common alkaline lysis method, the glass beads can effectively break the yeast cell wall, the new silica matrix membrane and buffer system can efficiently and specifically bind the plasmid DNA, and at the same time can maximize the removal of proteins and other impurities, the whole process is convenient and fast, no need to use toxic and harmful reagents, and can be processed at the same time for multiple samples. In addition to yeast cells, it can also be used in E. coli. Plasmid DNA extracted with this kit can be used in various molecular biology experiments, such as ligation, transformation, sequencing and library screening.Self-contained reagents: β-mercaptoethanol, anhydrous ethanol.Pre-experiment Preparation and Important Notes1. All components can be stably stored in dry, room temperature (15-30℃) environment for 1 year, the adsorption column can be stored at 2-8℃ for a longer period of time, and Buffer P1 with RNase A can be stably stored at 2-8℃ for 6 months.2. Before the first use, add all the RNase A solution to Buffer P1, mix well, and store at 2-8℃.3. Anhydrous ethanol should be added to Buffer PW before first use according to the instructions on the reagent bottle label.4. Before use, please check whether Buffer P2 and Buffer N3 are crystallized or precipitated. If there is any crystallization or precipitation phenomenon, it can be clarified by taking a water bath at 37℃ for a few minutes to restore the clarity.5. Be careful not to touch Buffer P2 and Buffer N3 directly, and tighten the lid immediately after use.6. The amount of plasmid extracted is related to the yeast strain, plasmid copy number, culture conditions, etc. Usually, yeast plasmid copy number is very low, which is difficult to be detected by electrophoresis or spectrophotometer method.Procedure1. Take 1-5 ml of yeast culture (maximum 5×107 yeast cells, generally for Saccharomyces cerevisiae OD = 1.0, equivalent to 1-2×107 cells/ml) and add it to a centrifuge tube (self-provided), centrifuge for 30 seconds at 12,000 rpm (~13,400×g), collect the bacterial precipitate, and aspirate as much as possible to discard the supernatant.2. Add 250µl Buffer P1 to the bacterium (please check if RNase A has been added first) and resuspend the precipitate.3. Add 40mg of Glass Beads to the above mixture and vortex and shake for 10 minutes.4. Add 250 µl of Buffer P2 to the centrifuge tube, mix gently by turning up and down 6-8 times, and let stand at room temperature for 5-10 minutes, at which time the bacterial solution should become clear and viscous.Note: Mix gently, do not shake violently, so as not to interrupt the genomic DNA, resulting in genomic DNA fragments mixed in the extracted plasmid. If the solution does not become clear, it suggests that the amount of bacteria may be too large and the lysis is not complete, and the amount of bacteria should be reduced.5. Add 350 µl of Buffer N3 to the centrifuge tube and immediately mix gently up and down 6-8 times, at which point a white flocculent precipitate appears, and centrifuge at 12,000 rpm for 20 minutes.Note: Buffer N3 should be mixed immediately after addition to avoid localized precipitation.6. Column Equilibration: Add 200 µl of Buffer PS to the Spin Columns DM in the collection tube, centrifuge at 12,000 rpm for 1 minute, pour off the waste liquid from the collection tube, and place the column back into the collection tube.7. Add the supernatant from step 5 to the adsorbent column that has been loaded into the collection tube, taking care not to aspirate the precipitate.Note: The maximum volume of the adsorption column is 750 µl, and the solution is passed through the column in 2 times.8. Centrifuge at 12,000 rpm for 1 minute, pour off the waste liquid in the collection tube and place the adsorption column back into the collection tube.9. Add 150 µl Buffer PB to the adsorbent column, centrifuge at 12,000 rpm for 1 min, pour off the waste liquid in the collection tube, and put the adsorbent column back into the collection tube.10. Add 750 µl Buffer PW to the adsorption column (please check that anhydrous ethanol has been added first), centrifuge at 12,000 rpm for 1 minute, and pour off the waste liquid in the collection tube.11. Place the column back into the recovery collection tube and centrifuge at 12,000 rpm for 2 minutes, pouring off the waste liquid. Leave the column at room temperature for several minutes to dry thoroughly.Note: The purpose of this step is to remove residual ethanol from the adsorption column; ethanol residue can interfere with subsequent enzymatic reactions (digestion, PCR, etc.).12. Place the adsorbent column in a new centrifuge tube, add 50-100 µl of Buffer EB to the center of the adsorbent membrane dropwise, let it stand at room temperature for a few minutes, centrifuge at 13,000 rpm for 1 minute, and collect the plasmid solution into the centrifuge tube. Store the plasmid at -20°C.Attention:1) To increase the recovery efficiency of the plasmid, the resulting solution can be reintroduced into the adsorbent column, left at room temperature for a few minutes, centrifuged at 13,000 rpm for 1 minute, and the plasmid solution collected into a centrifuge tube.2) When the plasmid copy number is low or >10 kb, Buffer EB is preheated at 65-70°C in a water bath, which can increase the extraction efficiency.3) Usually yeast plasmids have very low copy number and are difficult to detect by electrophoresis or spectrophotometry. If the extracted plasmid is to be used in the next step of the experiment, it is usually recommended to use 1-5µl of the plasmid as PCR template, and 5-10µl of the plasmid for transformation of E. coli.4) Commercial high transformation efficiency receptor cells should be used for transformation of E. coli... Read More |