| Description | Starch hydrolases include α-amylase (α-AL, EC 3.2.1.1) and β-amylase (β-AL). α-Amylase randomly catalyzes the hydrolysis of α-1,4-glycosidic bonds in starch, producing reducing sugars such as glucose, maltose, maltotriose, and dextrins, while simultaneously Starch hydrolases include α-amylase (α-AL, EC 3.2.1.1) and β-amylase (β-AL). α-Amylase randomly catalyzes the hydrolysis of α-1,4-glycosidic bonds in starch, producing reducing sugars such as glucose, maltose, maltotriose, and dextrins, while simultaneously reducing the viscosity of starch, hence it is also known as the liquefying enzyme. α-Amylase is widely distributed, from microorganisms to higher plants. Detection Principle: Starch hydrolases catalyze the hydrolysis of starch to produce reducing sugars. These reducing sugars reduce 3,5-dinitrosalicylic acid (DNS) to produce a brown-red-colored compound with an absorption peak at 540 nm. The amylase activity is calculated by measuring the rate of increase in absorbance at 540 nm. α-Amylase is heat-stable, but β-amylase can be inactivated by heating at 70°C for 15 minutes. Therefore, after the crude enzyme extract is treated at 70°C for 15 minutes, only α-amylase can catalyze starch hydrolysis. Detection Range: 0.0156 - 1 mg/mL Sensitivity: 0.0078 mg/mL Applicable Samples: Saliva, animal tissues, plant tissues (seeds or newly germinated seedlings) Note: The detection range and sensitivity are based on the standard. The actual detection range and sensitivity for activity need to be calculated according to the sample conditions.G1501772Component96TStorageG1501772ADNS Reagent40 mL2-8℃. Store in the dark.G1501772BSubstrate1EA2-8℃G1501772CStandard1EA2-8℃Note: Before formal testing, it is recommended to perform a preliminary test with 2-3 samples expected to have significant differences.User-Prepared Instruments and Reagents1.Microplate reader or visible spectrophotometer (capable of measuring absorbance at 540 nm)2.96-well plate or micro glass cuvettes, adjustable micropipettes and tips3.Centrifuge, water bath4.Deionized water5.Homogenizer (for tissue samples)Experimental Procedure1. Reagent PreparationReagent NameReagent PreparationNotesDNS ReagentReady-to-use; Equilibrate to room temperature before use.Store at 4°C protected from light.SubstrateBefore use, add 20 mL deionized water, invert and shake several times, heat until dissolved.Unused reagent can be stored at 4°C for one week. If precipitate forms, heat to 70°C to dissolve.StandardBefore use, add 1 mL deionized water to dissolve, obtaining a 10 mg/mL standard (Glucose) stock.Can be stored at 4°C for 2 weeks.2. Standard Curve SetupDilute the 10 mg/mL standard stock solution with deionized water to concentrations of 1, 0.5, 0.25, 0.125, 0.0625, 0.0313, and 0.0156 mg/mL as shown in the table below.TubeStandard VolumeDeionized Water Volume (µL)Standard Concentration (mg/mL)Std.140µL (10 mg/mL)3601Std.2200µL of Std.12000.5Std.3200µL of Std.22000.25Std.4200µL of Std.32000.125Std.5200µL of Std.42000.0625Std.6200µL of Std.52000.0313Std.7200µL of Std.62000.0156Note: The standard curve must be generated with each experiment. Diluted standard solutions are unstable and must be used within 4 hours3. Sample PreparationNote: Fresh samples are recommended.3.1 Animal TissueWeigh approximately 0.1 g of tissue. Add 1 mL of deionized water and homogenize. Transfer the homogenate to a centrifuge tube. Let it stand at room temperature for 15 minutes, vortexing every 5 minutes for sufficient extraction. Centrifuge at 6,000 g for 10 minutes at room temperature. Aspirate the supernatant and dilute to 10 mL with deionized water. Mix well. This is the amylase stock solution.3.2 Plant TissueWeigh approximately 0.1 g of tissue. Add 1 mL of deionized water and grind. Sonicate for 5 minutes (power 20%, pulse 3s on, 7s off, repeat 30 times). Let it stand at room temperature for 15 minutes, vortexing every 5 minutes for sufficient extraction. Centrifuge at 6,000 g for 10 minutes at room temperature. Aspirate the supernatant and dilute to 10 mL with deionized water. Mix well. This is the amylase stock solution.3.3 Saliva, and Other Liquid SamplesAssay directly. It is recommended to perform a preliminary test to determine the appropriate dilution factor.Note:For animal tissues with high fat content, remove the upper fat layer after centrifugation before collecting the supernatant.If protein concentration measurement is required, use Aladdin's BCA Protein Quantification Kit (B665595) or Ready-to-Use BCA Protein Quantification Kit (R1491648).4. Assay Steps4.1 Preheat the microplate reader or visible spectrophotometer for at least 30 minutes. Set the wavelength to 540 nm. For spectrophotometers, zero the instrument with deionized water.4.2 Preheat a water bath to 70°C.4.3 Take 75 µL of sample and incubate in a boiling water bath for 5 minutes. This will be used as the Control tube.4.4 Sample Measurement (Add reagents sequentially into microcentrifuge tubes as below):ReagentBlank Tube (µL)Standard Tube (µL)Test Tube (µL)Control Tube (µL)Deionized Water75000Standard (various conc.)07500Sample007575 (boiled sample)Heat at 70°C for 15 min, then cool.Substrate00750Incubate in a constant temperature water bath at 40°C for 5 min.DNS Reagent150150150150Substrate75750754.5 Mix well. Incubate in a boiling water bath for 5 minutes. Cool. Transfer 200 µL to a 96-well plate or micro glass cuvette. Measure the absorbance at 540 nm. Calculate ΔA test = A test - A control ; ΔA standard = A standard - A blank. Note: Each sample requires a control tube. The blank tube only needs to be prepared once. It is recommended to perform a preliminary test with 2-3 samples expected to have significant differences before the formal experiment. If A test > 2, the enzyme activity is too high, and the sample must be diluted with deionized water to an appropriate concentration (multiply by the dilution factor in the calculation). If ΔA test < 0.005, re-extract the sample reducing the final volume of deionized water used for dilution.5. Calculation of Results 5.1 Standard Curve Plotting Plot the standard concentration (y-axis) against ΔA standard (x-axis) to generate the standard curve. Substitute ΔA test into the standard curve equation to calculate y (mg/mL). 5.2 α-Amylase Activity Calculation (1) Based on Sample Fresh Weight Calculation (1) Based on Sample Fresh Weight Calculation Unit Definition: One unit of enzyme activity is defined as the amount of enzyme that catalyzes the production of 1 mg of reducing sugar per minute per gram of tissue. Calculation Formula: α-Amylase Activity (U/g weight) = y × V sample ÷ (W × V sample ÷ V total ) ÷ T × n = 2 × y ÷ W × n (2) Based on Sample Protein Concentration (2) Based on Sample Protein Concentration Calculation Unit Definition: One unit of enzyme activity is defined as the amount of enzyme that produces 1 mg of reducing sugar per minute per milligram of tissue protein. Calculation Formula: α-Amylase Activity (U/mg prot) = y × V sample ÷ (Cpr × V sample ) ÷ T × n = 0.2 × y ÷ Cpr × n (3) Based on Liquid Sample Volume Calculation Unit Definition: One unit of enzyme activity is defined as the amount of enzyme that produces 1 mg of reducing sugar per minute per liter of liquid sample. Calculation Formula: α-Amylase Activity (U/L) = 1000 × y ÷ T × n = 200 × y × n Parameter Definitions: y: Concentration of reducing sugar calculated from the standard curve (mg/mL) V sample : Volume of sample added to the reaction system (0.075 mL) W: Sample weight (g) V total : Total volume of the sample extract (10 mL) T: Enzymatic reaction time (5 minutes) n: Sample dilution factor Cpr: Sample protein concentration (mg/mL) 1000: Conversion factor between liters and milliliters (1 L = 1000 mL)6. Representative ResultsTypical Standard Curve: y = 0.4948x - 0.0179, R² = 0.9982Precautions1. Biochemical reagents are generally irritating and potentially biologically toxic. For your safety and health, please use appropriate biosafety precautions throughout the experiment, including wearing lab coats, masks, gloves, and head covers. Perform experiments in a fume hood or biosafety cabinet.2. This product is for research use only. Not for use in clinical diagnosis... Read More | Format:2-ComponentEnzyme:Horseradish peroxidase | Products contentNote: The amount of individual primers used is 1 µl, each N7-end primer can perform 10 DNA library constructs, and each kit can perform 240 DNA library constructs.Products IntroductionThis kit is a companion kit to the transposase-based Rapid DNA Library Construction Kit for Products contentNote: The amount of individual primers used is 1 µl, each N7-end primer can perform 10 DNA library constructs, and each kit can perform 240 DNA library constructs.Products IntroductionThis kit is a companion kit to the transposase-based Rapid DNA Library Construction Kit for Illumina platform library construction. Each kit contains one N5 primer and 24 N7 primers, which can be used to prepare 24 different single-ended Index libraries. All reagents provided in the kits have been subjected to stringent quality control and functional validation to maximize the stability and reproducibility of library construction. The libraries can be used for sequencing on Illumina platforms such as HiSeq X-10/4000/2500/2000 and MiSeq. Provide your own instruments, reagents and consumables1. Magnetic frame: DynaMagTM-2 is recommended.2. DNA purification and recovery kit: It is recommended to use Kangwei DNA purification and recovery kit by magnetic bead method.3. DNA building kit: It is recommended to use the Kangwei Century transposase method second-generation sequencing rapid DNA building kit.4. Anhydrous ethanol.5. Reaction tubes: It is recommended to use low adsorption PCR tubes with 1.5 ml centrifuge tubes; Tip: It is recommended to use a high quality filter tip to prevent contamination of kits and library samples. Pre-experiment Preparation and Important NotesPlease centrifuge briefly before opening the cap so that the liquid collects at the bottom of the tube to avoid cross-contamination between different primers. procedureFor the use of the CombiVision Second Generation Sequencing Multisample Primer Kit, please follow the CombiVision Second Generation Sequencing Rapid DNA Library Kit protocol. Index N501 Primer for Illumina Index N901-N996 Primer for Illumina... Read More | Product contentP666142Component200 TStorageP666142ABuffer P160 mLRTP666142BBuffer P260 mLRTP666142CBuffer N380 mLRTP666142DBuffer PB35 mLRTP666142EBuffer PW (concentrate)25 mLRTP666142FBuffer EB30 mLRTP666142GRNase A (10 mg/mL)600 µLRTP666142HSpin Columns DM with Collection Tubes200 EART Product contentP666142Component200 TStorageP666142ABuffer P160 mLRTP666142BBuffer P260 mLRTP666142CBuffer N380 mLRTP666142DBuffer PB35 mLRTP666142EBuffer PW (concentrate)25 mLRTP666142FBuffer EB30 mLRTP666142GRNase A (10 mg/mL)600 µLRTP666142HSpin Columns DM with Collection Tubes200 EART Product IntroductionThis kit is suitable for extracting 1-5 ml of bacterial solution. Based on the lysis of cells by alkaline lysis method, it adopts a unique silica matrix membrane adsorption technology and reagent formulation, and efficiently and exclusively binds plasmid DNA in solution by centrifugal adsorption columns in a high-salt state, and each adsorption column can adsorb a maximum of 30 µg of plasmid DNA, and removes proteins, genomes, RNAs, and other impurities to the greatest extent possible. The plasmid DNA obtained can be directly used for cell transfection, PCR, digestion, sequencing, ligation and other biological experiments.Self-contained reagent: 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 into Buffer P1, mix well, and store it at 2-8°C. Before use, leave it at room temperature for a period of time, and then use it after recovering to room temperature.3. Anhydrous ethanol should be added to Buffer PW according to the instructions on the label of the reagent bottle before first use.4. If precipitation is found in Buffer P2, Buffer N3, or Buffer PB before use, the clarification can be restored by water bath at 37℃ for a few minutes (please do not shake Buffer P2 violently).5. Be careful not to touch Buffer P2, Buffer N3 and Buffer PB directly, and tighten the lid immediately after use.6. The amount and purity of extracted plasmid is related to the concentration of bacterial culture, strain type, plasmid size, plasmid copy number and other factors.Procedure1. Take 1-5 ml of the overnight culture and add it to a centrifuge tube (self-prepared), centrifuge for 30 seconds at 13,000 rpm (~16,200×g) to collect the bacterial precipitate, and discard the supernatant as much as possible.2. Add 250 µl of Buffer P1 to the centrifuge tube with the bacterial precipitate (please check that RNase A has been added first), mix well using a pipette or vortex shaker, and suspend the bacterial precipitate.Note: If the bacterial mass is not thoroughly mixed, it will affect the lysis effect, resulting in low extraction and purity.3. Add 250µl of Buffer P2 to the centrifuge tube and mix gently up and down 4-6 times, mixing well to lyse the organisms, at which point the solution should become clear and viscous.Note: Mix gently, do not shake vigorously to avoid interrupting the genomic DNA and causing the extracted plasmid to be mixed with genomic DNA fragments. This step should take no more than 5 minutes to avoid damage to the plasmid.4. Add 350 µl of Buffer N3 to the centrifuge tube and immediately mix gently up and down for 8-10 times, mixing well so that a white flocculent precipitate should appear. centrifuge at 13,000 rpm for 5 minutes.Note: Buffer N3 should be mixed immediately after addition to avoid localized precipitation.5. Transfer the supernatant obtained in step 4 to the Spin Columns DM that have been loaded into the collection tube, centrifuge at 13,000 rpm for 30 seconds, pour off the waste liquid from the collection tube, and place the column back into the collection tube.6. Add 150 µl Buffer PB to the adsorption column and centrifuge at 13,000 rpm for 30 seconds.7. Add 400 µl Buffer PW to the adsorption column (please check that anhydrous ethanol has been added first), centrifuge at 13,000 rpm for 1 minute, and pour off the waste liquid in the collection tube.8. Place the adsorbent column in a new centrifuge tube (supplied), add 50-100 µl Buffer EB to the middle of the adsorbent membrane, leave it at room temperature for 2 minutes, centrifuge at 13,000 rpm for 1 minute, and collect the plasmid solution into the centrifuge tube. -The plasmid solution was collected into the centrifuge tube.Note: 1) To increase the recovery efficiency of the plasmid, the resulting solution can be reintroduced into the adsorbent column, left at room temperature for 2 minutes, centrifuged at 13,000 rpm for 1 minute, and the plasmid solution collected into a centrifuge tube.2) For low plasmid copy number or >10 kb, Buffer EB is preheated at 65-70°C in a water bath to increase extraction efficiency... Read More | V669947 Component 50T Storage V669947A Buffer GL 15 mL RT V669947B Buffer GW1 (concentrate) 13 mL RT V669947C Buffer GW2 (concentrate) 15 mL RT V669947D Buffer RE 10 mL RT V669947E Proteinase K 12.5 mg RT V669947F Proteinase K Storage Buffer 1.25 mL RT V669947G Spin Columns RS with Collection Tubes V669947 Component 50T Storage V669947A Buffer GL 15 mL RT V669947B Buffer GW1 (concentrate) 13 mL RT V669947C Buffer GW2 (concentrate) 15 mL RT V669947D Buffer RE 10 mL RT V669947E Proteinase K 12.5 mg RT V669947F Proteinase K Storage Buffer 1.25 mL RT V669947G Spin Columns RS with Collection Tubes 50 RT V669947H RNase-Free Centrifuge Tubes (1.5 mL) 50 RTProductsThis kit is suitable for the extraction of viral RNA and DNA from fresh or frozen plasma, serum and cell-free body fluids. It is easy to operate as it does not require the use of organic solvents such as phenol and chloroform for extraction. The kit uses a unique buffer system to enable efficient and specific binding of viral nucleic acids in lysate to silica gel centrifugal adsorption columns. Inhibitors of PCR and enzyme reactions as well as residual impurities can be efficiently removed in a two-step effective rinsing step, and finally high purity viral nucleic acids can be obtained by using a low-salt buffer or water for elution. The purified viral nucleic acid is free of protein, nuclease and other impurities, and can be used directly in PCR, RT-PCR, Real-Time PCR, blotting experiments and so on.Self-contained reagent: anhydrous ethanol.Pre-experiment and Important Notes1. Add 1.25ml Proteinase K Storage Buffer to Proteinase K to dissolve it and store it at -20℃. Do not leave the prepared Proteinase K at room temperature for a long time, and avoid repeated freezing and thawing to avoid affecting its activity. Do not add Proteinase K directly into Buffer GL.2. Repeated freezing and thawing of the sample should be avoided, as this may result in smaller DNA fragments and a decrease in the amount of extracted DNA.3. Avoid repeated freezing and thawing of serum or plasma, which can lead to protein denaturation or precipitation, reducing the viral titer and thus affecting the yield of extracted viral nucleic acids.4. Anhydrous ethanol should be added to Buffer GW1 and Buffer GW2 according to the label instructions of the reagent bottle before first use.5. Check Buffer GL for crystallization or precipitation before use. If crystallization or precipitation occurs, redissolve Buffer GL in a water bath at 56℃.Procedure1. Take a 1.5 ml centrifuge tube (self-provided) and add 20 µl Proteinase K.2. Add 200 µl serum or plasma to the centrifuge tube. Add 200µl Buffer GL and vortex and shake for 15 seconds.Note: 1) Sample volume less than 200 µl can be made up by adding 0.9% NaCl (self-provided). 2) In order to ensure effective lysis of the sample, the sample needs to be mixed well with Buffer GL after adding Buffer GL.3. Incubate at 56°C for 15 minutes, centrifuge briefly, and collect the solution from the wall of the tube to the bottom of the tube.4. 250 µl of anhydrous ethanol was added, vortexed and shaken for 15 seconds, left at room temperature for 5 minutes, centrifuged briefly, and the solution on the wall of the tube was collected at the bottom of the tube.Note: If the ambient temperature exceeds 25°C, anhydrous ethanol should be used after pre-cooling on ice.5. Add the solution obtained in step 4 to the adsorbent column (RNase-Free Columns RS) that has been loaded into the collection tube, and if the solution cannot be added at one time, it can be transferred in several times. centrifuge the column at 12,000 rpm (~13,400 × g) for 1 min, pour off the waste liquid in the collection tube, and put the column back into the collection tube.6. Add 500 µl of Buffer GW1 to the adsorption column (check that anhydrous ethanol has been added before use), centrifuge at 12,000 rpm for 1 minute, pour off the waste liquid in the collection tube, and put the adsorption column back into the collection tube.7. Add 500 µl of Buffer GW2 to the adsorption column (check that anhydrous ethanol has been added before use), centrifuge at 12,000 rpm for 1 minute, pour off the waste liquid in the collection tube, and put the adsorption column back into the collection tube.Note: Step 7 can be repeated if further DNA purity is required.8. Add 500 µl of anhydrous ethanol to the adsorbent column and 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.9. Centrifuge at 12,000 rpm for 3 minutes and pour off the waste liquid in the collection tube. Leave the adsorption column at room temperature for several minutes to dry thoroughly.Note: The purpose of this step is the removal of residual ethanol from the adsorbent column; ethanol residue can interfere with subsequent enzymatic reactions (digestion, PCR, etc.).10. Place the adsorption column in a new collection tube (RNase-Free Centrifuge Tube), add 20-150 µl of Buffer RE or sterilized water overhanging the middle of the adsorption column membrane, leave it at room temperature for 2-5 minutes, and then centrifuge it at 12,000 rpm for 1 minute to collect the nucleic acid solution.Note: 1) If the downstream experiment is sensitive to pH or EDTA, you can use sterilized water for elution. The pH of the eluent has a great influence on the elution efficiency, if water is used as the eluent it should be ensured that its pH is 7.0-8.5 (the pH of water can be adjusted to this range with NaOH), and the elution efficiency is not high when the pH is lower than 7.0.(2) For long-term storage, please store the DNA solution at -20℃ and the RNA solution at -70℃.3) If the final concentration of DNA/RNA is to be increased, the DNA/RNA eluate obtained in step 10 can be re-spiked onto the adsorbent membrane and step 10 repeated... Read More |