| Description | Annexins are a family of calcium-dependent phospholipid-binding proteins that preferentially bind phosphatidylserine (PS). Under normal physiologic conditions, PS is predominantly located in the inner leaflet of the plasma membrane. Upon initiation of apoptosis, PS loses its asymmetric Annexins are a family of calcium-dependent phospholipid-binding proteins that preferentially bind phosphatidylserine (PS). Under normal physiologic conditions, PS is predominantly located in the inner leaflet of the plasma membrane. Upon initiation of apoptosis, PS loses its asymmetric distribution across the phospholipid bilayer and is translocated to the extracellular membrane leaflet marking cells as targets of phagocytosis. Once on the outer surface of the membrane, PS can be detected by fluorescently labeled Annexin V in a calcium-dependent manner. In early-stage apoptosis, the plasma membrane excludes viability dyes such as 4',6-diamidino-2-phenylindole （DAPI）, propidium iodide (PI), 7-AAD. These cells will stain with Annexin V but not a viability dye, thus distinguishing cells in early apoptosis. However, in late stage apoptosis, the cell membrane loses integrity thereby allowing Annexin V to also access PS in the interior of the cell. A viability dye can be used to resolve these late-stage apoptotic and necrotic cells (Annexin V, viability dye-positive) from the early-stage apoptotic cells (Annexin V positive, viability dye-negative). This kit is suitable for the identification and enumeration of dead cells, such as apoptotic or necrotic cells, by flow cytometry.A1456541Components20 T50 T100 TStorageQuantity Per TestA1456541A10× Annexin V Binding Buffer5 mL10 mL20 mL2-8℃200 µL per 0.5-1.0 × 10⁵ cellsA1456541BAnnexin V -PE-Cy7200 µL500 µL1000 µL2-8℃. Store in the dark.10 µL per 0.5-1.0 × 10⁵ cellsA1456541CDAPI Staining Solution (25 µg/mL)20 µL50 µL100 µL2-8℃. Store in the dark.1 µL per 0.5-1.0 × 10⁵ cellsNote: The recommended number of cells to stain per test is 0.5-1.0 × 10⁵ cells.Precautions1. Please try to avoid light when using to slow down the quenching of fluorescence.2. DAPI Solution is toxigenic and mutagenic; handle with care.3. Due to the calcium dependence of the Annexin V:PS interaction, it is critical to avoid buffers containing EDTA or other calcium chelators during Annexin V experiments.Instruction for use 1. Dilute 10X Binding Buffer to 1X using distilled water (1 mL 10X Binding Buffer + 9 mL ddH2O).2. Wash cells twice with cold PBS and then resuspend the desired amount of cells in Annexin V Binding Buffer at a concentration of 0.5-1.0x 10⁶ cells /mL. 3. Add 10 µL of Annexin V-PE-Cy7 and 1 µL of DAPI staining solution to 100 µL of cell suspension.4. Add 100 µL of 1x Binding Buffer to each assay. Gently vortex the cells and incubate for 10 min at RT (25°C) in the dark.5. Perform flow cytometry analysis within 1 hr... Read More | Inquire | Product introduction：Product introduction：Cell Cycle Assay Kit Plus ( Cell Cycle Assay Kit Plus ) has certain applicability for live cells and fixed cell cycle detection. For different types of cells, whether it is applicable or not needs to be determined after testing. Cell Cycle Product introduction：Product introduction：Cell Cycle Assay Kit Plus ( Cell Cycle Assay Kit Plus ) has certain applicability for live cells and fixed cell cycle detection. For different types of cells, whether it is applicable or not needs to be determined after testing. Cell Cycle Assay Kit Plus ( Cell Cycle Assay Kit Plus ) uses RedNucleus I staining to detect cell cycle. RedNucleus I is a far-infrared nucleic acid dye with cell membrane permeability, which can quickly enter living cells, specifically bind to DNA, and perform cell cycle detection on living cells without RNase digestion. Compared with the traditional PI staining method, the cells do not need to be broken or fixed, and the operation is simpler. RedNucleus I is a fluorescent dye of double-stranded DNA, and the fluorescence intensity after binding to double-stranded DNA is proportional to the content of double-stranded DNA. The intracellular DNA content can be measured by flow cytometry, and then the cell cycle analysis can be carried out according to the distribution of DNA content. After RedNucleus I staining, assuming that the fluorescence intensity of G0 / G1 phase cells is 1, the theoretical value of the fluorescence intensity of G2 / M phase cells containing two copies of genomic DNA is 2, and the fluorescence intensity of S phase cells undergoing DNA replication is between 1-2. In addition, RedNucleus I is compatible with dyes such as Horizon BV / BUV, FITC and R-PE, and can be periodically detected after sample staining.The kit is usually used to detect the cell cycle of cultured adherent or suspended cells. If it is used for cell cycle detection of tissues, the tissues must be digested into a single cell state.Matters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. this product is applicable to the detection of living cells and fixed cell cycle with certain limitations. Whether it is applicable to different types of cells needs to be determined after testing. If fixation is needed, it is recommended to use ice bath pre cooling 75-80% ethanol -20 ℃ to fix cells overnight. 3. fluorescent dyes have quenching problems. Please try to avoid light during storage and use to slow down fluorescence quenching. 4. for your safety and health, please wear experimental clothes and disposable gloves.Instruction： Experimental materials ( self-provided )：①cell lines or other cell samples ( self-prepared ) ；②This kit ; ③ trypsin ( self-prepared ) ;④ Cell culture medium containing FBS ( self-prepared ) ; Experimental procedure： 1.Preparation of cell samples : ( 1 ) ( This step is for adherent cells, if suspended cells, can be carried out directly step ( 2 ) ) Digest cells with trypsin, add cell culture medium, gently blow away cells, collected into the centrifuge tube. Note : The number of cells on the machine needs to reach 50,000 and above, so the initial number of cells collected needs to be sufficient. ( 2 ) Centrifuged about 1000 g for 3-5 min to precipitate cells. Carefully remove the supernatant, add about 1 mL of ice bath pre-cooled 1 × staining buffer ( 10 × staining buffer diluted with diH2O at 1 : 10 ), re-suspend the cells. Repeat once. ( 3 ) Centrifuged about 1000 g for 3-5 min to precipitate cells. After the supernatant was discarded, 1 mL of culture medium was added to re-suspend the cells ( for fixed cells, 1 × PBS can also be used to re-suspend ). Gently flick the bottom of the centrifuge tube to properly disperse the cells to avoid cell aggregation. 2.Staining : 4 µL of RedNucleus I staining solution was added to each tube of cell samples, slowly and fully mixed, and incubated at room temperature in dark for 20 min ( or incubated at 37 ° C in dark for 5-10 min ). The optimal incubation time of different cells is different, and the staining time can be adjusted and optimized according to the actual staining effect to obtain a more ideal staining effect. 3.Flow cytometry detection and analysis : Excited at 638 nm by flow cytometry, it is recommended to detect in RL3 or FL4 channels, or use RL1 and RL2 channels. Cell DNA content analysis and light scattering analysis were performed using appropriate analysis software.Scope of application：Cell cycle detection... Read More | Product introduction：PMA qPCR live bacteria detection kit provides an effective means to detect bacterial activity. This kit provides a mixture of PMA dye and SYBR green dye based qPCR. The optimal amount of dye and the number of samples that can be processed may vary depending on the type ofProduct introduction：PMA qPCR live bacteria detection kit provides an effective means to detect bacterial activity. This kit provides a mixture of PMA dye and SYBR green dye based qPCR. The optimal amount of dye and the number of samples that can be processed may vary depending on the type of sample. PMA is a DNA binding dye with high affinity, especially with double stranded DNA. The dye itself has weak fluorescence, but it can emit brighter fluorescence after binding with nucleic acids. PMA is impermeable to the cell membrane, so it can selectively modify the DNA of dead cells with damaged membrane. After bllight (~464 nm) photolysis of PMA modified DNA, the photoreactive azido group on PMA is converted into highly reactive azene radical, which reacts with any hydrocarbon moiety near the DNA binding site to form a stable covalent nitrogen carbon bond, resulting in permanent DNA modification. This modification process will make the DNA insoluble, and it will be lost together with cell debris in the later genomic DNA extraction process. The unbound PMA remaining in the solution reacts with water molecules under strong light irradiation and decomposes into hydroxylamine compounds without cross-linking activity, so that it can no longer covalently bind DNA. Based on this characteristic of PMA, our company combines PMA and qPCR technology to form a new detection method - PMA qPCR, which is used for the screening of live bacteria. At present, the method has been validated in a variety of bacterial strains as well as yeast, fungi, viruses and parasites. The treatment of complex samples, such as feces or soil, may require optimization of sample dilution, dye concentration, and light treatment time. Treatment of diluted samples, such as water testing, may require filtration or concentration prior to dye treatment. Component： 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 ( used for the photolysis step after PMA modified DNA ) ;② Bacterial genomic DNA extraction kit ; 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 procedureNote : 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. 3. 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 : Product parameters：Pma: ex = 464 nm; Ex/em = 510/610 nm (following photolysis and reaction with dna/rna)Scope of application：Live bacteria detection Matters needing attention：1.Please instantaneously centrifuge the product to the bottom of the tube before use, and then carry out subsequent experiments ; 2.the kit components contain fluorescent dyes, and attention should be paid to avoiding light during use and preservation ; 3.For your safety and health, please wear experimental clothes and disposable gloves... Read More | This reagent kit is designed based on the principle that biotin and Streptavidin have a strong affinity. After the primary antibody of rabbit or mouse origin binds to the corresponding target antigen, the biotinylated antibody in this kit • • Rabbit/mouse universal secondary antibody This reagent kit is designed based on the principle that biotin and Streptavidin have a strong affinity. After the primary antibody of rabbit or mouse origin binds to the corresponding target antigen, the biotinylated antibody in this kit • • Rabbit/mouse universal secondary antibody specifically binds to the primary antibody; The biotin labeled on the secondary antibody binds to streptavidin labeled with peroxidase (HRP), forming an antigen-specific primary antibody biotinylated secondary antibody streptavidin complex labeled with HRP. HRP can catalyze substrate colorimetry, thereby inferring the presence and distribution of the tested antigen. The biotinylated secondary antibody and SA-HRP used in this reagent kit all adopt optimized labeling and purification techniques, which make their staining more sensitive and have a lower background. They are suitable for detecting formalin fixed paraffin embedded tissue sections, as well as frozen sections, cell slides, freshly prepared blood smears, etc. The rabbit/mouse universal Streptavidin HRP kit is suitable for use with aladdin ready to use or concentrated antibodies. Composition：Note: This reagent kit is only suitable for IHC experiments where the primary antibody is an immune or mouse derived antibodNotes:1. Add 1 drop (approximately 50) to each slice µ l) Calculation: 3ml can make 60 slices, and 18ml can make 360 slices.2.For tissues with abundant endogenous biotin content, it is best to use endogenous biotin blockers for blocking when using this kit.3. DAB working solution is prepared and used immediately, and the prepared working solution is effective within 1 hour in the dark at 2-8 ° C.4. During the experiment, avoid drying the tissue slices, so the amount of working fluid used during each incubation step must be sufficient to ensure complete coverage of the tissue sample, and incubation should be carried out in a wet box as much as possible.5. To obtain the best experimental results, please make sure to optimize the experimental conditions and reagent dosage.6. DAB is a suspected carcinogen, please take necessary protective measures when using it. 7. This product is only for scientific research and cannot be used for human reactions or treatments.Operation steps：1. Routine processing of samples such as paraffin or frozen tissue sections or cell slides to be tested.1) Preparation for staining of tissue sections or cell slides: a. Dewaxing and hydration of paraffin sections: bake at 60 º C for 1 hour, dewaxing twice with xylene for 5 minutes each time; Then immerse in gradient ethanol (anhydrous ethanol anhydrous ethanol 95% 85% 75% ethanol) and distilled water for 5 minutes each for hydration. b. Frozen sections and cell climbing sections (or climbing sections) were soaked in 0.01 M pH 7.4 PBS and washed 3 times for 5 minutes. Then cover the tissue (or cells) with 0.1% Triton X-100 and infiltrate for 15 minutes. Wash twice with 0.01 M pH 7.4 PBS for 5 minutes.2) Antigen repair of paraffin sections: In most cases, high-pressure repair with citric acid buffer is suitable for paraffin tissue sections. Preparation of repair solution: Add 10 ml of citric acid buffer (IHC antigen repair solution, 100 x) to 1 L of deionized water, and mix well. Repair process: The repair solution is added to a high-pressure cooker, and the repaired slices are immersed in the repair solution (must have no tissue). Cover the pressure cooker cover, heat until evenly sprayed with steam, and start timing from the spraying. After 1-2 minutes, the pressure cooker leaves the heat source and cools naturally to room temperature. Remove the slices, rinse with distilled water, and rinse twice with PBS (0.01 M pH 7.4) for 3 minutes each time.2. Add an appropriate amount of Solution A white solution, which is an endogenous peroxidase blocking solution, and incubate at room temperature for 10 minutes, then rinse thoroughly with PBS.3. Add an appropriate amount of Solution B white solution dropwise, which is sealed with normal sheep serum working solution. Incubate at room temperature for 10 minutes and shake dry.4. Add an appropriate amount of primary antibody working solution (commercial ready to use antibodies or concentrated antibodies diluted in appropriate proportions) dropwise, incubate according to experimental requirements, and then rinse thoroughly with PBS.5. Add an appropriate amount of Solution C yellow solution, namely biotin labeled sheep anti rabbit/mouse secondary antibody working solution, incubate at room temperature for 10 minutes, and rinse thoroughly with PBS.6. Add an appropriate amount of Solution D red solution, which is HRP labeled streptavidin. Incubate at room temperature for 10 minutes and rinse thoroughly with PBS.7. Preparation of DAB color working solution: According to the required amount, mix DAB-A and DAB-B in a volume ratio of 1:19 to obtain DAB color working solution. Alternatively, one drop (approximately 50) can be added per milliliter of reagent B µ l) Reagent A, mix well.8. Color development: Add an appropriate amount of DAB color development working solution to the tissue section or cell slide that needs to be developed, and the color development time is generally 1-5 minutes. Observe and control the color development time under a microscope. When the optimal color development effect is achieved, rinse with tap water to terminate the color development. The colored slices are re stained, dehydrated and transparent, and can be stored for a long time after sealing... Read More |