| Description | 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 | Lipid peroxidation is the degradation of lipids that occurs as a result of oxidative damage and is a useful marker for oxidative stress. Polyunsaturated lipids are susceptible to an oxidative attack, typically by reactive oxygen species, resulting in a well-defined chain reaction with the productionLipid peroxidation is the degradation of lipids that occurs as a result of oxidative damage and is a useful marker for oxidative stress. Polyunsaturated lipids are susceptible to an oxidative attack, typically by reactive oxygen species, resulting in a well-defined chain reaction with the production of end products such as malondialdehyde (MDA). Lipid peroxidation may contribute to the pathology of many diseases including atherosclerosis, diabetes, and Alzheimer′s.Lipid peroxidation (MDA) assay kit has been used to determine the levels of malondialdehyde (MDA).Suitability: Suitable for the measurement of malondialdehyde (MDA) in a variety of samples including tissue, cells and plasmaPrinciple: In this kit, lipid peroxidation is determined by the reaction of MDA with thiobarbituric acid (TBA) to form a colorimetric (532 nm)/fluorometric (λex= 532/λem= 553 nm) product, proportional to the MDA present... Read More | functional group:carboxylic acid Description:Liposome Kit has been used for the preparation of liposomes. Composition:Cholesterol, 9 µmol/package L-α-Phosphatidylcholine (egg yolk), 63 µmol/package Stearylamine, 18 µmol/package | Inquire | Product introduction: The MA qPCR live bacteria detection kit provides an effective means for detecting bacterial activity. The kit provides a mixture of PMA dye and qPCR based on SYBR Green dye. The optimal amount of dye and the number of samples that can be treated may vary depending on theProduct introduction: The MA qPCR live bacteria detection kit provides an effective means for detecting bacterial activity. The kit provides a mixture of PMA dye and qPCR based on SYBR Green dye. The optimal amount of dye and the number of samples that can be treated may vary depending on the type of sample. PMA is a high-affinity DNA-binding dye, especially with double-stranded DNA. The dye itself has weak fluorescence, but it can emit brighter fluorescence after binding to nucleic acids. PMA is impermeable to cell membranes, so it can selectively modify the DNA of dead cells with damaged membranes. After the PMA-modified DNA is photolyzed by blue light ( ~ 464 nm ), the photoreactive azide group on the PMA is converted into a highly reactive nitrene radical, which reacts with any hydrocarbon near the DNA binding site to form a stable covalent nitrogen-carbon bond, resulting in permanent DNA modification. This modification process will make DNA insoluble and lost with cell debris during the later genomic DNA extraction process. The unbound PMA remaining in the solution reacts with water molecules under strong light irradiation to decompose into hydroxylamine compounds without cross-linking activity, so that it can no longer covalently bind to DNA. Based on this feature of PMA, PMA was combined with qPCR technology to form a new detection method, PMA-qPCR, for the screening of live bacteria. At present, the method has been verified in a variety of bacterial strains, yeast, fungi, viruses and parasites. The treatment of complex samples, such as manure or soil, may require optimization of sample dilution, dye concentration, and light treatment time. The treatment of diluted samples, such as water testing, may require filtration or concentration prior to dye treatment. Matters needing attention:1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. the components of the kit contain fluorescent dyes. Avoid light during use and storage. 3. for your safety and health, please wear experimental clothes and disposable gloves.Product parameters:Spectral characteristics :PMA: Ex = 464 nm; Ex/Em = 510/610 nm (following photolysis and reaction with DNA/RNA)Component: PMA:Ex = 464 nm; Ex/Em = 510/610 nm (following photolysis and reaction with DNA/RNA) Instruction: Precautions before use: 1.This live bacteria detection kit distinguishes dead bacteria and live bacteria according to cell membrane permeability. Many methods of killing bacteria cause damage to the cell membrane and are therefore compatible with this kit. But some methods, such as ultraviolet irradiation, may not immediately cause cell membrane rupture. Therefore, before selecting this kit, it is necessary to carry out literature search and pre-experiment to determine whether the kit is suitable for the bacterial type and killing method you choose. 2.After PMA treatment, the bacteria need to be photolyzed to covalently bind the dye to dead cell DNA. Photolysis operations can use blue or white light sources. Generally speaking, the brighter the lamp, the higher the efficiency of the photolysis step. Non-LED lamps ( such as halogen lamps ) may heat your sample and have a negative impact on the analysis. Ice is required to cool the sample during irradiation. 3.Sample can be cryopreservation after photolysis. Frozen samples before PMA treatment photolysis may damage the cell membrane and produce false negative results. If the sample needs to be frozen before detection, it is recommended to perform a pre-experiment first. 4.Part of the mechanism of PMA is to remove PMA covalently modified DNA from the sample by precipitation ; therefore, when extracting genomic DNA, it is necessary to use the same volume of genomic DNA eluent for volume normalization. The positive control can use the genomic DNA of living cells. 5.In order to verify the effectiveness of PMA in the test sample, the Ct ( dCt ) changes between- / + PMA can be compared. Experimental materials ( self-provided ):①Light source ( for the photolysis step after PMA modification of DNA ) ; ② Bacterial genomic DNA extraction kit ; ③ effective qPCR primers corresponding to the sample type Experimental procedure: 1.Suck 10 µL of E.coli bacterial solution in liquid LB medium, and culture E.coli in the bacterial incubator overnight or longer to the logarithmic growth phase ( OD600 ≈ 1.0 ) ; Note : The culture time is adjusted according to the experiment. 2.Two portions of live E.coli, 400 µL each, were placed in a clean centrifuge tube ; 3. ( Recommended ) Preparation of dead E.coli. If the dead E.coli is needed as a control, the dead E.coli can be obtained by heating the living E.coli in a water bath at 95 °C for 5 min, or at 58 °C for 3 h. the subsequent operation of the dead E. coli is the same as that of the living E. coli ; 4.Two copies of live E.coli, one without PMA treatment, and one with 25 µM PMA treatment ( the optimal PMA concentration for treating different types or different sources of bacteria needs to be consulted in the relevant literature ) ; 5.The PMA-treated samples were placed on a shaker at room temperature and incubated in the dark for 10 min to fully mix the dye with the sample ; 6.Exposure of the sample, you can use blue or white light source, irradiation time to explore their own. For example, a 60 W blue light can be used for 15 min. Note : 1 If a halogen lamp is used, we recommend that the PMA-treated sample tube be placed on an ice block 20 cm away from the light source. Ice should be placed in a transparent tray. Adjust the light source to point directly to the sample, photolysis for 5-15 min ; if the bacteria obtained from the environment are directly used for experiments, due to the complexity or turbidity of the environmental samples, the photolysis time needs to be prolonged appropriately. 7.Treated and untreated live E.coli 5000 × g, centrifuged for 10 min, remove the supernatant ; 8.Select the appropriate genomic DNA extraction kit according to the sample type, and use the same elution volume for each group of samples when elution DNA. Note : DNA extraction steps refer to the instructions of the kit used. Part of the mechanism of action of PMA is to remove PMA-bound DNA from the sample by precipitation ; therefore, when extracting genomic DNA, each group should use the same volume of genomic DNA eluent for volume normalization ( the amount of genomic DNA extracted from dead bacteria and live bacteria is inconsistent, so the concentration of the two is significantly different ). 9.Preparation of reaction mixture according to the following system : Note : 1 For the DNA extracted by commercial DNA extraction kit, the qPCR template was optimized with 2 µL as the initial volume ; 2 The template volume should not exceed 10 % of the final reaction volume ; 3 Template concentration : gDNA as template, usually 1-10 ng ; the final concentration of PCR primers is usually 0.4µM, which can get better results. When the reaction performance is poor, the primer concentration can be adjusted in the range of 0.2-1µM. 10.Slightly vortex the reaction mixture, transfer the fixed volume to the PCR tube. 11. Test procedure Note : 1 The extension time is adjusted according to the instrument ; the Taq enzyme in mix can be activated within 2 min, but the genomic DNA may require longer denaturation time, which can be increased at this time, and the specific denaturation time can be adjusted according to the sample type.12. ( Optional ) Data analysis Using live bacteria and dead bacteria as controls, the number of live cells in the sample was analyzed and calculated. It is recommended to verify the suitability of primers and PCR procedures before starting PMA qPCR detection of live bacteria. Calculation of dead and living bacteria control dCt ( 1 ) After the end of qPCR, the Ct value of each sample was calculated by instrument software ; ( 2 ) By calculating the dCt of each control bacteria, it was judged whether PMA successfully inhibited the amplification of dead bacterial DNA. The calculation is as follows : dCt live = Ct ( live, PMA treated ) -Ct ( live, PMA untreated ) dCt die = Ct ( die, PMA treated ) -Ct ( die, PMA untreated ) ( 3 ) The dCt expectation of living bacteria is close to 0 ± 1, which indicates that PMA does not affect the amplification of living cell DNA ;( 4 ) The expected value of dCt of dead bacteria is greater than 4 ( dCt is 4 means that it is reduced by about 16 times, that is, 94 % of dead bacterial DNA is removed ; a dCt of 8 indicated a decrease of about 250 times, that is, 99.6 % of the dead bacterial DNA was removed ).( 5 ) The dCt of dead bacteria depends on many factors, including : strain / cell type ; the way bacteria are killed ; the concentration of PMA used ; amplified sequence length. 13. Calculation of the proportion of viable ( optional ) bacteria If the control results of dead and live bacteria are normal, the proportion of live bacteria in the sample can be calculated.( 1 ) Calculate the dCt value of the sample : dCt sample = Ct ( sample, PMA treated ) -Ct ( sample, PMA untreated ) ( 2 ) Conversion of dCt value to live bacteria ratio : PMA inhibition multiple = 2 ( sample dCt ) Viable bacteria % = 100 / PMA inhibition multiple 14. ( Optional ) Calculate the absolute number of live bacteria If you want to calculate the absolute number of viable bacteria in the sample, you need to use a known number of target bacteria genomic DNA to make a standard curve. It is recommended that the diluted concentrations of several groups of genomes are within the range of the qPCR analysis system.( 1 ) qPCR was performed with the appropriate genome, and the Ct value was used as the ordinate, and the number of cells was used as the abscissa. The R2 value is calculated to determine the linearity, and the slope and y-axis intercept are displayed. ( 2 ) Calculate the copy number of the experimental samples : Ct = slope * cell number + y axis intercept ( y = mx + b ) Bacterial count sample = ( Ct-y axis intercept ) / slope Note : The live bacterial DNA was not lost during the purification process. Examples : Scope of application:Live bacteria detection... Read More |