| Description | Inquire | Annexin V ( annexin-V ) is a Ca2 + dependent phospholipid binding protein with a molecular weight of 35-36 KD, which can selectively bind to phosphatidylserine ( PS ). Phosphatidylserine ( PS ) is mainly distributed in the inner side of the cell membrane, that is, the side adjacent to the cytoplasm.Annexin V ( annexin-V ) is a Ca2 + dependent phospholipid binding protein with a molecular weight of 35-36 KD, which can selectively bind to phosphatidylserine ( PS ). Phosphatidylserine ( PS ) is mainly distributed in the inner side of the cell membrane, that is, the side adjacent to the cytoplasm. In the early stage of apoptosis, different types of cells will turn phosphatidylserine out to the cell surface and expose to the extracellular environment. At this time, using Annexin V labeled with fluorescent protein PE, that is, Annexin V-PE, combined with phosphatidylserine ( PS ), the eversion of phosphatidylserine, an important feature of apoptosis, can be directly detected by flow cytometry. Normal cells will not be stained by Annexin V-PE, apoptotic or necrotic cells will be stained by Annexin V-PE. Annexin V-PE can be used in combination with partially non-permeable nuclear dye ( 7-AAD / PI ) to distinguish cells at different stages of apoptosis. RedNucleus II provided in this kit is a far-red dye that belongs to an anthraquinone compound and cannot penetrate the intact cell membrane of living cells and early apoptotic cells. It is non-permeable, but can quickly stain the nucleus / dsDNA in dead and permeable cells. RedNucleus II is an ideal substitute for propidium iodide ( PI ) and 7-AAD.Combined with Annexin V-PE, it has better spectral characteristics without compensation regulation : it is not excited by ultraviolet light and does not overlap with PE / PE homologues, so it can be combined with FITC, PE and purple fluorescent dyes for multicolor analysis. When combined with Annexin V-PE, RedNucleus II was excluded from living cells and early apoptotic cells, while late apoptotic cells and dead cells were double-positive for Annexin V-PE and RedNucleus II. Annexin V-PE / RedNucleus II apoptosis detection kit can be detected by flow cytometry or other fluorescence detection equipment. Components: Components A598354(10T) A598354(50T) A598354(100T) A. 1×Annexin V Combining buffer solution 10 mL 50 mL 50 mL×2 B. Annexin V-PE 50 µL 250 µL 500 µL C. RedNucleus II 100 µL 500 µL 1 mLProduct parameters：Annexin v-pe:ex/em=488/578 nmrednucleus ii:ex/em=635/695 NMUsage method:1. Experimental design: Blank tube: Negative control group cells, without Annexin V-PE/RedNucleus II. Used to regulate voltage.Single staining tube: Positive control group cells were treated with Annexin V-PE alone/RedNucleus II alone. Used for adjusting compensation.Detection tube: Add Annexin V-PE/RedNucleus II to the processed cells. After adjusting the voltage compensation using blank tubes and single dye tubes, obtain the required flow data.2. Collect cells(1) For suspended cells:a. After inducing cell apoptosis, centrifuge at 1000 rpm for 5 minutes, discard the supernatant, collect the cells, gently resuspend the cells in PBS, and count them.Note: PBS resuspension cannot be omitted. The process of PBS resuspension also serves to wash cells, ensuring the subsequent binding of Annexin V-PE.b. Take 5 × 104-1 × 105 resuspended cells, centrifuge at 1000 rpm for 5 minutes, discard the supernatant, and add 100 µ L of 1 × Annexin V binding buffer to gently resuspend the cells. c. Add 5 µ L Annexin V-PE and mix gently.d. Add 5 µ L of RedNucleus II staining solution and mix gently.e. Incubate at room temperature (20-25 º C) in the dark for 15 minutes. Aluminum foil can be used to avoid light. During the incubation process, cells can be resuspended 2-3 times to improve staining efficiency.(2) For adherent cells:a. Suck out the cell culture medium into a suitable centrifuge tube, wash the adherent cells with PBS once, and add an appropriate amount of trypsin cell digestion solution (without EDTA) to digest the cells. Incubate at room temperature until gently blowing can remove the trypsin cell digestion solution when the adherent cells are blown down. Overdigestion of pancreatic enzymes should be avoided.Note: For adherent cells, the trypsin digestion step is crucial. If the trypsin digestion time is too short, cells need to be blown hard to detach, which can easily cause damage to the cell membrane and lead to false positives of cell necrosis; If the digestion time is too long, it can also cause cell membrane damage and false positives of cell necrosis, and even affect the binding of phosphatidylserine and Annexin V-PE on the cell membrane, thereby interfering with the detection of cell apoptosis.b. Add the cell culture medium collected in the previous step, gently blow down the cells, transfer them to a centrifuge tube, centrifuge at 1000 rpm for 5 minutes, discard the supernatant, collect the cells, gently resuspend the cells in PBS and count them.Note: Adding the cell culture medium from the previous step is very important. On the one hand, it can collect cells that have already been suspended and undergone apoptosis or necrosis. On the other hand, the serum in the cell culture medium can effectively inhibit or neutralize residual trypsin. The residual trypsin will digest and degrade the subsequently added Annexin V-PE, leading to staining failure.c. Take 5 × 104-1 × 105 resuspended cells, centrifuge at 1000 rpm for 5 minutes, discard the supernatant, and add 100 µ L of 1 × Annexin V binding buffer to gently resuspend the cells. d. Add 5 µ L Annexin V-PE and mix gently.e. Add 5 µ L of RedNucleus II staining solution and mix gently.f. Incubate at room temperature (20-25 º C) in the dark for 15 minutes. Aluminum foil can be used to avoid light. During the incubation process, cells can be resuspended 2-3 times to improve staining efficiency.3. Result analysis:(1) Flow cytometry detection:a. After incubation, 400 µ L of 1 × Annexin V binding buffer can be directly added to resuspend the cells, and immediately detected on the machine. Annexin V-PE is excited by 488 nm/566 nm laser, and the fluorescence emission spectrum is detected at 578 nm (BL2 (FL2)/YL1 channel), while the RedNucleus II channel emission spectrum is approximately at 695 nm (RL1 (FL4) channel).b. On the scatter plot of the bivariate flow cytometer, live cells are shown in the lower left quadrant, which is (Annexin V-PE -/RedNucleus II -); The lower right quadrant represents early apoptotic cells, which are (Annexin V-PE+/RedNucleus II -); The upper right quadrant represents necrotic and late stage apoptotic cells, which are (Annexin V-PE+/RedNucleus II+); The upper left quadrant displays naked nuclear cells, which are (Annexin V-PE -/RedNucleus II+).(2) Fluorescence microscopy detection:a. Centrifuge at 1000 rpm for 5 minutes, collect cells, and gently resuspend them in 400 µ L of 1 × Annexin V binding buffer. Transfer the cells to a 96 well plate and settle for a moment or perform cell smear, then observe under a fluorescence microscope.b. Annexin V-PE is compatible with PE filters. RedNucleus II can use a far red long pass filter.Matters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. to reduce the process of apoptosis, the incubation process can be operated on ice, but the incubation time should be extended to at least 30 min. 3. as apoptosis is a rapid process, it is recommended that samples be analyzed within 1 h after staining. 4. for adherent cells, digestion is a key step. If there are floating cells when adherent cells induce apoptosis, the floating cells and adherent cells should be collected and stained. Handle adherent cells with care to avoid artificial damage to cells. The trypsin digestion time is too short, and the cells need to be blown hard to fall off, which is easy to cause damage to the cell membrane and excessive intake of rednucleus II; If the digestion time is too long, the cell membrane is also prone to damage, and even affect the binding of phosphatidylserine and annexin v-pe on the cell membrane. When digesting, spread pancreatin on the bottom of the well plate, fully contact the pancreatin with the cells when shaking gently, then pour out most of the pancreatin, use the remaining small amount of pancreatin to digest for a period of time, and terminate when the gap between cells increases and the bottom of the bottle is spotted. Try not to use EDTA in the digestive juice, which will affect the binding of annexin V to PS. 5. after the adherent cells are digested with trypsin, it is recommended to stain after recovering in the optimal culture conditions and medium for about 30 min to avoid false positives. 6. in order to avoid losing cells when washing cells, you can use a large tip over a small tip to aspirate. 7. the optimal concentration of dye is determined by the specific experimental requirements. 8. fluorescent dyes have quenching problems. Please try to avoid light during storage and use to slow down fluorescence quenching. 9. for your safety and health, please wear experimental clothes and disposable gloves.Scope of application：Early apoptosis detection, annexin V Kit... Read More | Calcein AM /PI Double Staining Kitis utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stains viable and dead cells, respectively(Fig. 1). Calcein-AM, an acetoxymethyl ester of calcein, is highly Calcein AM /PI Double Staining Kitis utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stains viable and dead cells, respectively(Fig. 1). Calcein-AM, an acetoxymethyl ester of calcein, is highly lipophilic and cell membrane permeable. Though Calcein-AM itself is not a fluorescent molecule, the calcein generated from Calcein-AM by esterase in a viable cell emits a strong green fluorescence (excitationat 490 nm, emission at515 nm). Therefore, Calcein-AM only stains viable cells. On the other hand, PI, a nuclei staining dye, cannot pass through a viable cell membrane. It reaches the nucleus by passing through disordered areas of dead cell membrane, and intercalates with the DNA double helix of the cell to emit red fluorescence (excitation: 535 nm,emmision: 617 nm). Since both calcein and PI-DNA can be excited with 490 nm, simultaneous monitoring of viable and dead cells is possible with a fluorescence microscope. With 545 nm excitation, only dead cells can be observed (Fig. 1). Since optimal staining conditions differ from cell line to cell line, we recommend that a suitable concentration of PI and Calcein-AM be individually determined. Please note that PI is suspected to be highly carcinogenic;careful handling is required.Required Equipment and Materials:Microscope with 490 nm excitation filter and 530 nm emission filter；CO2incubator；10 µl and 200 µl adjustable pipettes, PBSSolution A (Calcein-AM)；Solution B (PI) Storage Condition: -20oC ；Shipping Condition: blue ice.Application:Assay Procedure1)Add 2.5 µl Solution A and 12.5 µl Solution B to 5 ml PBS to prepare assay solution.*2)Wash the cell with PBS several times to remove residual esterase activity.3)Add 100uLof assay solution to200uL105~106CELLSsolution and incubate the mixture at 37oC for 15 min.4)Detect fluorescence using a fluorescence mircoscope with 490 nm excitationfor simultaneous monitoring of viable and dead cells.With 545 nm excitation, only dead cells can be observed.*The following steps may be necessary tooptimizethe suitable concentration of each reagent:1)Prepare dead cells by 10 min incubation in 0.1% saponin or 0.1-0.5% digitonin or by 30 min incubation in 70% ethanol.2)Stain dead cells with 0.1-10 µM PI solution to find a PI concentration that stains the nucleus only, not the cytosol.3)Stain dead cells with 0.1-10 µM Calcein-AM solution to find a Calcein-AM concentration that does not stain the cytosol. Then stainviable cells with that Calcein-AM solution to check whether the viable cell can be stained... Read More | Inquire | 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 |