| Description | Glycogen is a macromolecular polysaccharide composed of glucose and serves as one of the primary storage forms of sugar. It is mainly stored in the liver and muscles as reserve energy, referred to as liver glycogen and muscle glycogen, respectively. Liver glycogen regulates blood glucose Glycogen is a macromolecular polysaccharide composed of glucose and serves as one of the primary storage forms of sugar. It is mainly stored in the liver and muscles as reserve energy, referred to as liver glycogen and muscle glycogen, respectively. Liver glycogen regulates blood glucose concentration; when blood sugar rises, glycogen can be synthesized in the liver, and when blood sugar decreases, liver glycogen is broken down into glucose to supplement blood sugar. Therefore, liver glycogen is crucial for maintaining the relative balance of blood glucose. Muscle glycogen is the storage form of sugar in muscles. During strenuous exercise that consumes large amounts of blood sugar, muscle glycogen cannot be directly broken down into blood sugar but must first decompose to produce lactic acid, which circulates to the liver via the bloodstream and is converted into liver glycogen and glucose through gluconeogenesis. Detection Principle: Glycogen is extracted using a strong alkaline extraction buffer. Under strong acidic conditions, it forms a blue compound with the anthrone chromogen, which has a characteristic absorption peak at 620 nm. Within a certain concentration range, the glycogen content is linearly related to the absorbance at 620 nm. The glycogen content in the sample can be calculated based on the standard curve. Detection Range: 0.003125 - 0.25 mg/mL Sensitivity: 0.003125 mg/mL Applicable Samples: Animal tissues, bacteria, cellsG1501748Component96TStorageG1501748AExtraction Buffer120 mL2-8℃G1501748BChromogen1EA2-8℃. Store in the dark.G1501748CStandard1 mL2-8℃Note: It is recommended to perform preliminary experiments using 2-3 samples expected to have significant differences before formal testing.User-Provided Instruments and Consumables1.Microplate reader or visible spectrophotometer (capable of measuring absorbance at 620 nm)2.Low-temperature centrifuge, Water bath3.96-well plate or micro glass cuvettes, Adjustable pipettes and tips, EP tubes4.Deionized water, Concentrated sulfuric acidExperimental Procedure1. Reagent PreparationReagent NameReagent PreparationPrecautionsExtraction BufferReady-to-use; equilibrate to room temperature before use.Store at 4°C. Corrosive; please take protective measures during handling.ChromogenFirst, dissolve the powder in 7.2 mL of deionized water. Then slowly add 28.8 mL of concentrated sulfuric acid. Mix thoroughly after complete dissolution.Store at 4°C protected from light; valid for one week. Toxic; please take protective measures during handling.StandardStore at 4°C.2. Standard Curve SetupDilute the 1 mg/mL standard with deionized water to prepare standard solutions of 0.25, 0.1, 0.05, 0.025, 0.0125, 0.00625, and 0.003125 mg/mL as shown in the table below.No.Standard VolumeDeionized Water Volume (µL)Concentration (mg/mL)Std.1100µL of 1mg/mL3000.25Std.2160µL of Std.12400.1Std.3200µL of Std.22000.05Std.4200µL of Std.32000.025Std.5200µL of Std.42000.0125Std.6200µL of Std.52000.00625Std.7200µL of Std.62000.003125Note: A standard curve must be prepared for 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 1 month.3.1 TissuesWeigh 0.1 g of tissue and place it in a 10 mL test tube. Add 0.75 mL of Extraction Buffer. Boil in a water bath for 20 minutes (stopper the tube tightly to prevent water evaporation). Shake the tube every 5 minutes to mix thoroughly. After the tissue is completely dissolved, remove the tube and let it cool. Dilute to 5 mL with deionized water, mix well. Centrifuge at 8,000 g, 25°C for 10 minutes. Collect the supernatant for detection.3.2 Cells or BacteriaCollect 5 million bacteria or cells into an EP tube. Centrifuge and discard the supernatant. Add 0.75 mL of Extraction Buffer and disrupt the bacteria or cells by ultrasonication (power 200 W, ultrasonicate for 3 s, interval 10 s, repeat 30 times). Transfer to a 10 mL test tube. Boil in a water bath for 20 minutes (stopper the tube tightly to prevent water evaporation). Shake the tube every 5 minutes to mix thoroughly. Remove the tube and let it cool. Dilute to 5 mL with deionized water, mix well. Centrifuge at 8,000 g, 25°C for 10 minutes. Collect the supernatant for detection.Note: For protein concentration determination, Aladdin BCA Protein Quantification Kit (B665595) or Ready-to-Use BCA Protein Quantification Kit (R1491648) are recommended.4. Assay Steps4.1 Instrument Preparation: Preheat the microplate reader or visible spectrophotometer for at least 30 minutes. Set the wavelength to 620 nm. For visible spectrophotometers, zero the instrument with deionized water.4.2 Sample Assay: Add reagents sequentially to EP tubes as follows:ReagentBlank Tube (µL)Standard Tube (µL)Test Tube (µL)Sample0060Standard0600Deionized Water6000Chromogen2402402404.3 Mix well. Incubate in a 95°C water bath for 10 minutes (cap tightly to prevent evaporation). Cool. Transfer 200 µL to a 96-well plate or micro glass cuvette. Measure the absorbance at 620 nm, recorded as A blank, A standard, and A test. Calculate ΔA test = A test - A blank and ΔA standard = A standard - A blank. Note: It is recommended to perform preliminary experiments with 2-3 samples expected to have significant differences before formal testing. If ΔA test is less than 0.001, appropriately increase the sample amount. If ΔA test is greater than 1.5, dilute the sample further with deionized water (multiply the result by the dilution factor) or reduce the amount of sample used for extraction. 5. Result Calculation Note: We 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 Plotting Plot the standard curve with standard concentration as the y-axis and ΔA standard as the x-axis (using concentration as the y-axis facilitates calculation). Substitute ΔA test into x to calculate y (mg/mL). 5.2 Sample Glycogen Content Calculation (1) Based on sample mass: Glycogen (mg/g) = 1.11 × (y × V sample ) ÷ (W × V sample ÷ V total ) × n = 5.55 × y ÷ W × n (2) Based on sample protein concentration: Glycogen (mg/mg prot) = 1.11 × (y × V sample ) ÷ (V sample × Cpr) × n = 1.11 × y ÷ Cpr × n (3) Based on bacterial or cell count: Glycogen (mg/10⁴) = 1.11 × (y × V sample ) ÷ (Bacterial or Cell Count × V sample ÷ V total ) × n = 5.55 × y ÷ Bacterial or Cell Count × n Parameter Description: 1.11: Constant for converting glucose content measured by this method to glycogen content (i.e., 100 µg glucose color developed with anthrone reagent is equivalent to that of 111 µg glycogen). V sample : Volume of test sample added to the reaction system, 0.06 mL. W: Sample mass, g. V total : Total volume of the sample extract, 5 mL. n: Dilution factor. Cpr: Sample protein concentration, mg/mL. Bacterial or Cell Count: In units of 10⁴ (ten thousands)6. Result PresentationTypical Standard Curve: y = 0.1746x + 0.0027, R² = 0.9961(The following data and curve are for reference only; users must establish their own standard curve based on their experiment.)Precautions1. It is recommended to perform preliminary experiments using 2-3 samples expected to have significant differences before formal testing.2. This product is for scientific research use only and is not intended for clinical diagnosis. For your safety and health, please wear a lab coat and disposable gloves during operation... Read More | When apoptosis occurs, some DNA endonucleases will be activated. These endonucleases will cut off genomic DNA between nucleosomes and produce 180 bp-200 BP DNA fragments, which appear as a specific ladder pattern in agarose gel electrophoresis. When double strand or single strand breaks occurWhen apoptosis occurs, some DNA endonucleases will be activated. These endonucleases will cut off genomic DNA between nucleosomes and produce 180 bp-200 BP DNA fragments, which appear as a specific ladder pattern in agarose gel electrophoresis. When double strand or single strand breaks occur in genomic DNA, a large number of sticky 3'-oh ends will be generated, which can interact with YF under the catalysis of deoxyribonucleotide terminal transferase (TDT) ®/ CY dUTP binding can directly detect apoptotic cells by fluorescence microscopy or flow cytometry. This kind of method is called terminal deoxynucleotidyl transferase mediated nick end labeling (TUNEL). Because normal or proliferating cells have almost no DNA breaks, there is no 3'-oh formation and they can rarely be stained. TUNEL method can stain intact single apoptotic nuclei or apoptotic bodies in situ, can accurately reflect the typical biochemical and morphological characteristics of apoptosis, and can detect a very small number of apoptotic cells, so it is widely used in the study of apoptosis. This kit has a wide range of applications and can be used to detect apoptosis in frozen or paraffin sections, as well as cultured adherent cells or suspended cells. It can selectively detect apoptotic cells, but not necrotic cells or cells with DNA strand breaks caused by irradiation and drug treatment. This kit detects cell apoptosis with a short time-consuming, one-step staining reaction and can be detected after washing.Component： Instruction： Experimental materials (self provided)PBS buffer (1 x, pH~7.4). 0.2% Triton X -100 (PBS formulation). 0.1% Triton X -100 (PBS formulation, containing 5 mg/mLBSA)4% paraformaldehyde (prepared with PBS)Immunohistochemical penDewaxing solvent (paraffin section sample)Related reagents for paraffin section processingAnti fluorescence quenching and sealing agent. ddH2Oexperimental design. A. Positive control:Prepare positive control slides using DNaseI treatment. DNaseI can digest single or double stranded DNA and expose the 3 '- OH end, artificially causing cell apoptosis. One experiment per time is sufficient. (To verify if there are any issues with the experimental operation and reagent kit)B. Negative control:Use TUNEL Reaction Buffer without TdT Enzyme and replace TdT Enzyme with ddH2O. (Mainly to exclude non-specific staining caused by cell apoptosis, operational processes, and other reasons; and to adjust the exposure intensity of the shooting.)C. Experimental processing group.The experimental group operated normally according to the instructions.D. Experimental control group.The experimental group operated normally according to the instructions.Experimental steps1. Sample preparation:(1) For adherent cells or cell smearsa. Clean once with PBS.Note: If you are concerned that the cells on the cell smear may not adhere firmly, you can dry the sample to make the cells adhere more firmly.b. Fixation: Add an appropriate amount of 4% paraformaldehyde (prepared with PBS) and fix at 4 ℃ for 30 minutes. Clean twice with PBS.c. Translucency: Add an appropriate amount of 0.2% Triton X -100 (prepared with PBS) and let it penetrate at room temperature for 20 minutes. Clean twice with PBS.d. Step 2: TUNEL reaction.(2) For suspended cells or cell suspensionsa. Collect cells (3-5 x 106 cells), centrifuge at 1000 rpm for 5 minutes, and wash twice with PBS.b. Fixation: Add an appropriate amount of 4% paraformaldehyde (prepared with PBS) and resuspend the cells thoroughly. Fix at 4 ℃ for 30 minutes. Centrifuge at 2000 rpm for 5 minutes and clean twice with PBS.c. Translucency: Add an appropriate amount of 0.2% Triton X -100 (prepared with PBS) and let it penetrate at room temperature for 20 minutes. Centrifuge at 2000 rpm for 5 minutes and clean twice with PBS.d. Step 2: TUNEL reaction.(3) Paraffin tissue sectioninga. Dewaxing and hydration: Place the sliced samples sequentially in xylene I (10 min) → xylene II (10 min) → 100% ethanol I (5 min) → 100% ethanol II (5 min) → 95% ethanol (5 min) → 90% ethanol (5 min) → 80% ethanol (5 min) → 70% ethanol (5 min) → ddH2O rinse for 5 min, rinse twice.Note: Xylene is toxic and volatile. Please perform this operation in a fume hood.b. Use filter paper to dry the liquid around the sliced sample, and circle the sample contour with an immunohistochemical pen for downstream transparency and labeling.Note: If it is found that the contour circle of immunohistochemistry strokes is damaged in subsequent experimental operations, it needs to be redrawn in a timely manner.c. Transparency: Dilute 2 mg/mL of ProteinaseK solution with PBS in a ratio of 1:100 to a final concentration of 20 µ g/mL. Add 100 µ L dropwise to each sample to cover all sample areas. Incubate at 20-37 ℃ for 20 minutes.Note: Protein K can penetrate the cell membrane and nuclear membrane, allowing subsequent staining reagents to fully enter the nucleus for reaction and improve labeling efficiency. An excessively long incubation time increases the risk of tissue slices falling off the carrier film during subsequent washing steps, while a too short incubation time may result in insufficient permeability treatment and affect labeling efficiency. To obtain better results, the concentration, incubation time, and temperature of Protein K need to be optimized according to different types of tissue samples.d. Wash the slices twice with PBS, each time for 5 minutes. Use filter paper to remove excess liquid, and place the processed sample in a wet box to keep it moist.Note: Protein K must be washed thoroughly in this step, otherwise it will seriously interfere with subsequent labeling reactions.e. Step 2: TUNEL reaction.(4) Frozen tissue sectionsa. Fixation: Take out frozen sections and warm them back to room temperature. Add an appropriate amount of 4% paraformaldehyde (prepared with PBS) and fix at room temperature for 30 minutes. Wash twice with PBS for 10 minutes each time.Note: If you are concerned that formaldehyde cleaning may not be clean enough, it may affect the final dyeing effect. After formaldehyde fixation is completed, an appropriate amount of 2 mg/mL glycine can be added and washed for 10 minutes to neutralize the residual fixing solution, and then PBS cleaning can be carried out.b. Use filter paper to dry the liquid around the sliced sample, and circle the sample contour with an immunohistochemical pen for downstream transparency and labeling.Note: If it is found that the contour circle of immunohistochemistry strokes is damaged in subsequent experimental operations, it needs to be redrawn in a timely manner.c. Transparency: Dilute 2 mg/mL of ProteinaseK solution with PBS in a ratio of 1:100 to a final concentration of 20 µ g/mL. Add 100 µ L dropwise to each sample to cover all sample areas. Incubate at 20-37 ℃ for 20 minutes.Note: Protein K can penetrate the cell membrane and nuclear membrane, allowing subsequent staining reagents to fully enter the nucleus for reaction and improve labeling efficiency. An excessively long incubation time increases the risk of tissue slices falling off the carrier film during subsequent washing steps, while a too short incubation time may result in insufficient permeability treatment and affect labeling efficiency. To obtain better results, the concentration, incubation time, and temperature of Protein K need to be optimized according to different types of tissue samples.d. Wash the slices twice with PBS, each time for 5 minutes. Use filter paper to remove excess liquid, and place the processed sample in a wet box to keep it moist.Note: Protein K must be washed thoroughly in this step, otherwise it will seriously interfere with subsequent labeling reactions.e. Step 2: TUNEL reaction.(5) Positive treatment (only the positive control is subjected to this step, and other samples are directly subjected to the TUNEL reaction step)a. Dilute 10 x DNase I Buffer with ddH2O in a ratio of 1:10 to 1 x DNase I Buffer for later use.b. Drip 100 µ L of 1xDNase I Buffer onto the processed sample, covering all sample areas, and equilibrate at room temperature for 5 minutes.c. Dilute DNase I (2 U) with 1 x DNase I Buffer at a ratio of 1:100/ µ L) A working solution with a final concentration of 20 U/mL.d. Discard the buffer and add 100 µ Incubate DNase I working solution with a concentration of 20 U/mL at room temperature for 10 minutes.e. Discard DNase I working solution and clean twice with PBS.f. Step 2: TUNEL reaction.2. TUNEL reaction(1) Prepare TUNEL reaction solution (ready to use):/1 sample5sample10 sampleTdT enzyme1 µL5 µL10 µLYF®488/555/594/640 TUNEL Reaction Buffer49 µL245 µL490 µLTUNEL Total volume of reaction solution50 µL250 µL500 µL(2) For adherent cells, cell smears, or tissue sectionsa. Add 50 to each sample µ L TUNEL reaction solution, evenly cover the sample with the reaction solution. The appropriate time for dark incubation at 37 ℃ (recommended staining time for cells is 30 minutes to 1 hour, and tissue staining time is 2 hours).Note: 50 µ L TUNEL reaction solution is suitable for smear, slicing, or 96 well plates (other different well plates can adjust the volume of TUNEL reaction solution appropriately to cover cells). If the sample to be tested is a smear, slice, or in a 24 well plate, 12 well plate, or 6 well plate, anti evaporation film can be used, or self sealing bags or other appropriate materials can be used to cut circular plastic sheets slightly smaller than the holes. After adding TUNEL reaction solution dropwise, cover the sample to prevent the evaporation of TUNEL reaction solution and make the TUNEL reaction solution evenly cover the sample.b. Discard the TUNEL reaction solution, wash twice with PBS, and then wash three times with 0.1% Triton X -100 (PBS preparation, containing 5 mg/mL BSA) for 5 minutes each time. This way, free unreacted markers can be removed cleanly.c. (Optional) Add an appropriate concentration of 5 to each sample µ DAPI staining solution with a concentration of g/mL, incubated at room temperature in dark for 5 minutes. After staining, discard DAPI staining solution and wash twice with PBS for 5 minutes each time.d. (Optional) Slice sealing: Add 50 drops to each sample µ L anti fluorescence quenching sealing agent (anti fluorescence quenching sealing agent may not be suitable for certain dyes, it is recommended to conduct pre experimental testing for compatibility before the experiment), cover the cover glass, gently tap the cover glass with the blunt end of tweezers to remove bubbles and ensure complete sealing.e. Use filter paper to remove excess liquid and add 100 to the sample area µ Keep the sample moist with PBS and immediately observe under a fluorescence microscope.(3) For suspended cells or cell suspensionsa. Add 50 to each sample tube µ Gently resuspend cells in LTUNEL reaction solution and incubate at 37 ℃ in the dark for 30-1 hour. Gently resuspend cells with a micropipette every 15 minutes.b. Centrifuge at 2000 rpm for 5 minutes, discard TUNEL reaction solution, and wash twice with 0.1% Triton X -100 (PBS preparation, containing 5 mg/mLBSA) for 5 minutes each time. This way, free unreacted markers can be removed cleanly.c. Add 100 to each sample tube µ L concentration is 5 µ DAPI staining solution with a concentration of g/mL, incubated at room temperature in dark for 5 minutes.d. Join 400 µ L PBS resuspended cells and immediately detected with a flow cytometer or observed under a fluorescence microscope after smearing.Matters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. when the staining background is heavy or non-specific staining is obvious, the staining time can be appropriately reduced. 3. it is recommended to add negative control and positive control groups during the experiment. 4. please wear mask and gloves when using component A. if it contacts the skin, please wash it with plenty of water immediately. 5. fluorescent dyes have quenching problems. Please try to avoid light to slow down fluorescence quenching. 6. for your safety and health, please wear experimental clothes and disposable gloves.Product parameters：490/515 nm；Scope of application：Late apoptosis detection, TUNEL Kit... Read More | Products contentN665737Component24 T96 TStorageN665737ATPS V50 168 µL672 µL-20℃. Avoid freeze/thaw cycle.N665737B5×FA Reaction Buffer96 µL384 µL-20℃. Avoid freeze/thaw cycle.N665737CTS Buffer72 µL288 µL-20℃. Avoid freeze/thaw cycle.N665737D2×Products contentN665737Component24 T96 TStorageN665737ATPS V50 168 µL672 µL-20℃. Avoid freeze/thaw cycle.N665737B5×FA Reaction Buffer96 µL384 µL-20℃. Avoid freeze/thaw cycle.N665737CTS Buffer72 µL288 µL-20℃. Avoid freeze/thaw cycle.N665737D2×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 is 5 ng. We also have transposase library construction kits for 50 ng and 1 ng of human genomic DNA starting, in order to get a higher quality library, it is recommended to use different kits for different starting amount of DNA. 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 a starting template DNA input of 5 ng, 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 DNA purification and recovery kit by magnetic bead method.3. Library PCR primer kit: It is recommended to use 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 and 1.5 ml centrifuge tubes. Tips: It is recommended to use high quality filter tips 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 requirements: A260/A280 = 1.8-2.0. Sample DNA: dissolve 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 processprocedureDNA 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.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 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 centrifuge 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 centrifuge tube. Table: Suggested amount of magnetic beads for different segment selection recovery Library DNA fragment purificationWe recommend the use of the 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 ddH O 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 | Product introduction：Griess reagent can be used for spectrophotometric detection of nitrite. The reagent contains two chemicals, sulfonic acid and n- (1-naphthyl) ethylenediamine. Under acidic conditions, sulfamic acid is converted into diazonium salt by nitrite, which can form a highly Product introduction：Griess reagent can be used for spectrophotometric detection of nitrite. The reagent contains two chemicals, sulfonic acid and n- (1-naphthyl) ethylenediamine. Under acidic conditions, sulfamic acid is converted into diazonium salt by nitrite, which can form a highly colored azo dye with n- (1-naphthyl) ethylenediamine. This dye can be detected at 548 nm: because no is extremely unstable, it is oxidized to form nitrite and nitrate. Griess indirectly reflects the content of no by detecting the content of nitrite.Matters needing attention：1. before using Griess reagent, return it to room temperature and check the solution for precipitation. If Griess reagent I contains sediment when taken out, it can be placed in a 37 ℃ water bath until the sediment dissolves. 2. this product is potentially harmful. Avoid prolonged or repeated exposure. Avoid entering eyes, skin or clothing. Please wear lab clothes and disposable gloves for operation.Scope of application：No detectionComponent：Instruction：1.Griess Reagent I and II were taken out to restore the room temperature.2.Standard dilution : The standard NaNO2 ( 1-100 µM ) was diluted with the solution used for the sample to be tested. The standard was diluted to 1 µM, 10 µM, 20 µM, 40 µM, 80 µM and 100 µM, and 100 µL standard was added to each well. If the sample concentration is too low, the range of the standard curve can be appropriately reduced ( 1 µM, 2 µM, 3 µM, 4 µM, 6 µM, 8 µM, 10 µM ).3.Sample detection :( 1 ) According to the total volume of 200 µL / hole, 100 µL / hole sample was added to the 96-well plate ; if the sample is the supernatant of the culture medium, it can be sampled directly, and if there is sediment, the supernatant should be taken after centrifugation. If the sample is a cell or tissue, it can be quickly lysed by freeze-thaw, and then centrifuged to obtain the supernatant. The volume of less than 100 µL can be diluted with diH2O or 0.9 % NaCl ( corresponding standards also need to be diluted with diH2O or 0.9 % NaCl ).( 2 ) According to 50 µL / hole, Griess Reagent I was added to each hole.( 3 ) According to 50 µL / hole, Griess Reagent II was added to each hole.( 4 ) The absorbance was measured at 540 nm. If there is no 540 nm filter, 520-560 nm filter can also be. If there is no microplate reader or a suitable filter, the concentration of nitric oxide in the sample can also be determined by visual colorimetry. A more precise concentration gradient is required for the standard when visual colorimetric... Read More | Inquire |