| Description | Asp-Tyr-Lys-Asp-Asp-Asp-Asp-LysGently elutes FLAG fusion proteins from ANTI-FLAG? M1 and M2 affinity resins. Usual working concentration is 100 µg/ml. Will not elute 3X FLAG fusion proteins. For this application, use 3X FLAG Peptide | Inquire | Product introduction：Aladdin ® SE is a kind of fluorescent dye with amino reactive activity. The SE group of these dyes can react with the amino group to produce a stable amide bond. Compared with other similar dyes on the market, aladdin ® is a new generation of fluorescent dyes Product introduction：Aladdin ® SE is a kind of fluorescent dye with amino reactive activity. The SE group of these dyes can react with the amino group to produce a stable amide bond. Compared with other similar dyes on the market, aladdin ® is a new generation of fluorescent dyes with stronger stability, better water solubility and better fluorescence intensity. Product parameters： Absmax/Em(nm)：648/664；Absmax/Em(nm)：0.03；Extinction coefficient(ε)：240000；Optimal DOL(IgG)：3-6； Usage:1. Experimental materials(1) IgG: IgG must not contain amine chemicals that can react with dyes, such as amino acids, Tris, BSA, gelatin, etc. If IgG contains such chemicals, PBS buffer with pH~7.4 should be used for pre dialysis treatment. The presence of azide compounds does not affect the labeling reaction.(2) Anhydrous DMSO(3) NaHCO3(4) Sephadex gel G-25 dialysis column(5) PBS buffer (pH~7.4)(6) NaN3(7) BSA2. Marking methods and steps(1) Prepare to label antibodiesDilute the antibody with 0.1 M NaHCO3 solution (pH~8.3) to a final concentration of 2.5 mg/mL. If the product is pre diluted with phosphate buffer, such as PBS buffer (without amino compounds), approximately 1/10 volume of 1M NaHCO3 mother liquor can be directly added to the buffer to achieve a final NaHCO3 concentration of 0.1 M.Note: When the protein concentration is 2.5 mg/mL, the labeling efficiency is approximately 35%. Protein concentrations below 2.5 mg/mL can also be used for labeling, but the labeling efficiency will decrease. When the protein concentration is higher than 5 mg/mL, the labeling efficiency may be higher. Due to differences in buffer and protein purity, more precise labeling efficiency is determined by practical operating conditions. If the protein concentration is too low, it can be concentrated by ultrafiltration.(2) Prepare dye storage solutionPreheat one tube at room temperature µ YF of Mole ® SE, add 0.1 mL of anhydrous DMSO to the tube, thoroughly vortex dissolve the dye, and prepare a dye storage solution with a concentration of 10 mM. If a trace amount of protein is used for labeling reactions, the dye needs to be diluted to a lower concentration.Note: a The remaining dye storage solution should be stored at a low temperature of -20 ℃ for future use. If anhydrous DMSO is used to prepare dye storage solution, the dye can be stored for at least one month.b. Dyes can also be prepared with deionized water, but due to the slow hydrolysis of dyes in water, it is best to prepare water based storage solutions for immediate use.(3) Mark reaction stepsa. Stir or vortex the protein solution, gradually adding 15-25 drops µ L dye storage solution (10 mM), with a molar ratio of dye/protein in the range of 9:1 to 15:1. YF ® Please refer to the table above for the range of DOL (number of dyes bound to each protein molecule) for SE labeled IgG antibodies.b. Stir the reaction at room temperature for 1 hour, and for trace labeling, shake and incubate on a shaker for 1 hour.Note: At the same time of the binding reaction, proceed to step 2 (4) to balance the dextran gel G-25 dialysis column.(4) Isolation of marker proteins from reaction solutiona. PBS buffer (pH~7.4) was used to balance the dextran gel G-25 dialysis column (10 mm × 300 mm).b. Add the reaction solution from step 3 (b) to the column and elute with 1 x PBS buffer.The first washed out chromophore is a dye protein complex.Note: a For small-scale labeling reactions, in order to avoid excessive dilution of the product, ultrafiltration devices can be used to remove free dyes from the complex.b. After the binding reaction is completed, if the dye protein complex is not separated in time, 50 can be added µ Terminate the reaction with L 1M lysine. In most cases, this operation is not necessary because the remaining unreacted dyes have been fully hydrolyzed at the end of the reaction.3. Determine DOL(1) The determination of protein concentration and antibody concentration can be calculated using the following formula:C (mg/mL)={[A280- (Amax x x Cf)]/1.4} x dilution factor;a. C refers to the concentration of antibodies collected in the experiment;b. Dilution factor refers to the dilution factor used in photometric measurements;c. A280 and Amax refer to the absorbance at 280 nm and the absorbance at the absorption wavelength, respectively;d. Cf is the correction factor, YF ® Please refer to the table above for the Cf value of SE dyes;Note: The protein solution eluted through the column may have a high concentration when used directly for absorbance detection, so it needs to be diluted to approximately 0.1 mg/mL. The dilution factor (i.e. dilution factor) needs to be determined from the initial number of antibodies (e.g. 5 mg) and the overall elution of protein solutionEstimate based on the product.(2) Estimation of DOLDOL is calculated using the following equation:DOL=(Amax x x Mwt x Dilution Factor)/（ ε X C)a. Amax, dilution factor, C value has been clearly defined in 3 (1);b. Mwt refers to the molecular weight of IgG (150000);C. c ε It's YF ® The molar absorption coefficient of SE, refer to the table on the first page;d. Mark YF ® The optimal DOL value for SE IgG antibodies can be found in the table on the first page. Although DOL values may fluctuate, good experimental results can also be achieved.Matters needing attention：1. if the labeled protein needs long-term storage, it is recommended to add 5-10 mg/ml BSA and 0.01-0.03% NaN3 to prevent protein denaturation and microbial breeding. Store at 4 ℃ away from light. If glycerol with a final concentration of 50% is added, it can be stored at -20 ℃. It can be stably stored for more than one year. 2. keep away from light during operation. The mixing speed should be appropriate to avoid bubbles. 3. when installing the chromatographic column, try to make the column body uniform, the column surface flat, and free of bubbles and cracks. 4. pay attention to adding the sample when the column top buffer is tangent to the gel plane. When eluting, add the eluent when the sample is tangent to the gel plane. 5. other factors affecting the labeling efficiency also include temperature, reaction time, pH, the amount of fluorescent dye and protein, etc., which should be controlled. 6. for your safety and health, please wear laboratory clothes and disposable gloves.Scope of application：Protein nucleic acid labeling dye... Read More | Inquire | Reverse transcriptases are enzymes encoded in retroviruses viral genome. The enzyme is responsible for transcription of the viral RNA to produce a dsDNA that can be inserted into the host genome.Reverse transcriptases are multifunctional enzymes. These enzymes exhibit an RNA and DNA directed Reverse transcriptases are enzymes encoded in retroviruses viral genome. The enzyme is responsible for transcription of the viral RNA to produce a dsDNA that can be inserted into the host genome.Reverse transcriptases are multifunctional enzymes. These enzymes exhibit an RNA and DNA directed polymerase activity. In addition reverse transcriptases catalyze the degradation of RNA in an RNA-DNA hybrid. The exonucleolytic activity proceeds in a 5' ---> 3' direction. The RNA or DNA directed activity requires a template (RNA or DNA) and a primer. The following is a schematic illustration of the reaction:Unit definition: One unit incorporates 1 nanomole of tritiated dTMP into acid insoluble productsusing poly(A)•oligo(dT) 12-18 as the template-primer in 20 minutes at 37° C.ApplicationsHIV reverse transcriptase is used for research on the AIDS primer. However it can be substituted for AMV reverse transcriptase, which is mainly used to transcribe mRNA into double stranded cDNA, that can be inserted into prokaryotic vectors. The enzyme can also be used with either single stranded DNA or RNA templates to make probes for use in hybridization experiments. It can be used for labeling the termini of DNA fragments with protruding 5' termini. The enzyme can also be used to sequence DNAs by the dideoxy chain termination method of Sanger when the Klenow fragment of E. coli DNA polymerase I, or the T7 DNA polymerase yield unsatisfactory results.Reagents0.05 M Tris, pH 8.3, containing 0.008 M MgCl21 mg/ml polyadenylic acid in water (poly A)DNA primer:Oligo d(T)12-181 µ mole dTTP/mL stock solution[methyl-3H]-Thymidine 5'-triphosphate (3H-dTTP)dTTP-3H-dTTP working mix: Add 1-2 µL 3H-dTTP per mL of 100 nmol/mL dTTP in order to obtain 1 to 1.5 x 105 cpm/mL1% bovine serum albumin10% perchloric acid1% perchloric acidBuffer substrate reaction mixture: Prepare fresh, immediately before use:For each 1mL of reaction mixture required mix:0.7 mL Tris/HCl, pH 8.3, 0.008M MgCl20.3 mL 1 mg/mL poly(A) RNA template0.005 mL 0.02 mg/mL oligo d(T)12-18 DNA primer0.02mL 1% BSAEnzymedilute as needed wtih 0.05M Tris/HCl, pH 8.3, 0.008M MgCl2 containing 0.1 mg/mL (1%) BSAProcedurePipette into each tube as follows:Buffer substrate mix：0.1 mLdTTP-3H3-dTTP：0.1 mLEnzyme：5-10 µLIncubate 20 minutes at 37° C. Stop reaction by adding 1 ml 10% cold perchloric acid. Filter through 0.2µ manifold filters used with Millipore vacuum manifold. Wash four times using 2mL 1% cold perchloric acid/wash. Transfer filter to scintillation vials. Add 2mL Cellosolve (or 2-methoxyethanol) to dissolve filter. Filters become opaque upon addition of Cellosolve. Make sure filters are dissolved before proceeding. Add 10mL scintillation cocktail and count.Calculation... Read More |