| Description | Background informationAnnexins 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 Background informationAnnexins 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 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).We offer recombinant Annexin V conjugated to a numerous fluorophores, as well as an Annexin V biotin conjugate which can be detected with fluorophore-labeled streptavidin. By binding to PS, fluorophores labeled Annexin V can be used to detect and quantify apoptotic cells via flow cytometry or fluorescence microscopy. The excitation and emission maxima of the Annexin V conjugates are summarized in the following table. The excitation and emission maxima of the Annexin V conjugates are summarized in the following table.Cat.No.Ex/Em (nm)Formatrp226056NABiotinrp225999401/422AF405rp226057490/525AF488rp226060650/668AF647rp226002681/704AF680rp226003752/776AF750rp226053498/517FITCrp226004410/455Pacific Bluerp226006647/665Cy5rp226054650/660APCrp226055565/575PErp226058565/670PE-Cy5rp226059565/774PE-Cy7Precautions1. Please try to avoid light when using to slow down the quenching of fluorescence.2. Propidium Iodide 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 use1. Dilute 10X Binding Buffer (A1372288) 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 amounts of cells in Annexin V Binding Buffer at a concentration of 1.0-5.0 x 106 cells/mL.3. Add 5 µL of Annexin V-PE-Cy5 to 100 µL of the cell suspension. Stain with a viability dye, such as PI (P1373641; P1372285), 7-AAD (A1372406), or DAPI (D1372407) dyes, if desired.4. Gently vortex the cells and incubate for 10 min at RT (25°C) in the dark.5. Add 100 µL of 1X Binding Buffer to each assay. Analyze by flow cytometry within 1 hr... Read More | Inquire | Taq MasterMix is a premixed system composed of Taq DNA Polymerase, Mg2+, dNTPs, as well as PCR stabilizers and enhancers, with a concentration of 2 ×. The pre prepared PCR mixture makes the operation simpler and faster, and can minimize human error and contamination to the greatest extent Taq MasterMix is a premixed system composed of Taq DNA Polymerase, Mg2+, dNTPs, as well as PCR stabilizers and enhancers, with a concentration of 2 ×. The pre prepared PCR mixture makes the operation simpler and faster, and can minimize human error and contamination to the greatest extent possible. The original MasterMix formula results in high yield, strong repeatability, and good stability of amplified products. This product has been added with a dye (blue), and can be directly subjected to electrophoresis detection after the reaction is completed. The amplified PCR product has an "A" base attached to its 3 'end, making it suitable for direct use in T/A cloning. Mainly suitable for PCR amplification of DNA, DNA sequencing and other experiments. T665590Component5 mL25 mLStorageT665590A2×Taq MasterMix (Dye)5×1 mL5×5 mL-20℃. Avoid freeze/thaw cycle.T665590BddH₂O5×1 mL5×5 mL-20℃. Avoid freeze/thaw cycle.2×Taq MasterMix contains Taq DNA Polymerase, 3 mM Mg Cl₂ and 400 µM each dNTP. Quality control:After testing, there was no exogenous nuclease activity; PCR method for detecting residual DNA without host; Can effectively amplify single copy genes from multiple genomes.Usage:The following is an example of a PCR reaction system and reaction conditions for amplifying a 1 kb fragment using human genomic DNA as a template. In practical operation, corresponding improvements and optimizations should be made based on the template, primer structure, and target fragment size.1. PCR reaction system Reagent 50 µlReaction system Final concentration 2×Taq MasterMix（Dye） 25 µL 1× Forward Primer，10 µM 2 µL 0.4 µM Reverse Primer，10 µM 2 µl 0.4 µM Template DNA <0.5 µg <0.5 µg/50 µL ddH2O up to 50 µL /Attention: The primer concentration should be between 0.1 and 1.0 as the final concentration µ M serves as a reference for setting the range. In the case of low amplification efficiency, the concentration of primers can be increased; When non-specific reactions occur, the primer concentration can be reduced to optimize the reaction system.2. PCR reaction conditions Step Temperature Time / Pre denaturation 94℃ 2 min / Denaturation 94℃ 30 s 25-35 cycles Anneal 55-65℃ 30 s 25-35 cycles Extend 72℃ 30 s 25-35 cycles Finally extended 72℃ 2 min / Attention:1) In general experiments, if the annealing temperature is 5 ° C lower than the melting temperature Tm of the amplification primer, and the ideal amplification efficiency cannot be achieved, the annealing temperature should be appropriately reduced; When non-specific reactions occur, increase the annealing temperature to optimize the reaction conditions.2) The extension time should be set according to the size of the amplified fragment. The amplification efficiency of Taq DNA Polymerase in this product is 2 kb/min.3) The number of cycles can be set based on the downstream application of the amplification product. If the number of cycles is too small, the amplification amount is insufficient; If there are too many cycles, the probability of mismatches will increase, and non-specific backgrounds will be severe. So, while ensuring product yield, the number of cycles should be minimized as much as possible... Read More | Inquire | Inquire |