| Description | Product InfoQuality Control Tests:For catenated KDNA substrate, at least 90% of the DNA will be retained in the well of a 1% agarose gel.Decatenation of each batch of kDNA is tested with purified topoisomerase II.DescriptionAssays employing crude extracts for topo II activity based upon relaxation Product InfoQuality Control Tests:For catenated KDNA substrate, at least 90% of the DNA will be retained in the well of a 1% agarose gel.Decatenation of each batch of kDNA is tested with purified topoisomerase II.DescriptionAssays employing crude extracts for topo II activity based upon relaxation of supercoiled DNA can be complicated due to the presence of topo I in partially purified fractions. Additional complications arise with contaminating nuclease activity (due to Mg++) which degrade or nick the supercoiled substrate. These problems can be avoided by using a catenated DNA substrate prepared from the kinetoplast of the insect trypanosome Crithidia fasciculata. KDNA is an aggregate of interlocked DNA minicircles (mostly 2.5 kb) that form extremely large networks of high molecular weight. As a result, these networks fail to enter an agarose gel. Upon incubation with topo II, which engages DNA in a double stranded breaking and reunion cycle, minicircular DNAs are effectively released (decatenated). The decatenated minicircles move rapidly into the gel owing to their small size. This reaction will not occur with topoisomerase I. TopoGEN has modified the original gel system described by Miller et al. (see below) to allow additional discrimination of activities using kDNA. Shipping&storageThe marker is shipped at ambient temperature and should be stored a 4°C... Read More | 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 | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export | EPOCROSTM is a reactive polymer with an oxazoline group on the side chain and is used as a cross-linking agent for water-based resins. Among the water-based polymers developed to address environmental issues and the increasing use of water-based products due to VOC regulations and desolventing, the EPOCROSTM is a reactive polymer with an oxazoline group on the side chain and is used as a cross-linking agent for water-based resins. Among the water-based polymers developed to address environmental issues and the increasing use of water-based products due to VOC regulations and desolventing, the EPOCROSTM WS series is a “water-soluble type” with the following structure.Features and PropertiesHigher reactivity than water-based epoxy, melamine, blocked isocyanateVOC free (EPOCROS™ WS-300 and EPOCROS™ WS-700)High crosslinking density with a small amount addedOne-pack type with long usage timeImproves water resistance, solvent resistance, heat resistance, and the strength of films, etc.Adhesion-imparting possible to PET, OPP, PVC, etc.Fast dryingLow toxicity (Ames Test: Negative, Primary Skin Irritation Test: No irritation)WS Series Product LineupApplicationsNonwoven fabric bindersPigment printingCoatings (metals, films, leather)Paint and coatings, Primers (plastics, building materials, vehicles)AdhesivesMethodASSAY for Product Code DILW:One unit equals a decrease in absorbance of 1.0 per minute at 25°C at pH 7.5 with 2,6-dichlorophenolindophenol as the chromogen.Reagents0.2 M Tris⋅HCl buffer, pH 7.50.006 M NADH. Prepare fresh daily.0.0012 M Dichlorophenolindophenol (DCPIP) Prepare fresh daily.EnzymePrepare a 10 mg/ml solution of enzyme in 0.2 M Tris⋅HCl, pH 7.5.Dilute further immediately before use to give ΔA/min of 0.15-0.20.ProcedureAdjust spectrophotometer to 600 nm and 25°C.Pipette into cuvettes as follows:Mix quickly and measure the decrease in absorbance at 600 nm for 2-3 minutes.Determine the ΔA/min. from the initial linear portion of the curve. (Use portion of curve from t=0 to t=1 minute; the rate is linear for 1/2 to 1 minute.)Calculation... Read More | Malic Dehydrogenase is a ubiquitous enzyme, which exists in two isoforms in eukaryotic cells.Malic dehydrogenase exists as a dimer with each subunit containing an NAD-binding domain and a substrate-binding carboxy-terminal domain required for activity. Malic dehydrogenase is a cytoplasmic isozyme Malic Dehydrogenase is a ubiquitous enzyme, which exists in two isoforms in eukaryotic cells.Malic dehydrogenase exists as a dimer with each subunit containing an NAD-binding domain and a substrate-binding carboxy-terminal domain required for activity. Malic dehydrogenase is a cytoplasmic isozyme and an important catalyst in the tricarboxylic acid cycle.ReagentsA. 0.1 M Tris-HCl buffer (pH7.8)B. 0.01 M Phosphate buffer (KH2PO4-NaOH, pH 7.0)C. Triton X-100 solution (50 mg/ml)D. 0.01 M Phosphate buffer containing 0.1% Triton X-100 (KH2PO4-NaOH, pH 7.0)Dilute 20 ml of Triton X-100 solution (C) with approx. 800 ml of 0.01M Phosphate buffer (B). Fill up to 1,000 ml with 0.01M Phosphate buffer (B).E. NADH soluton Weigh 9 mg of NADH and dissolve in 0.1M Tris-HCl bufer (A). Fill up to 50 ml with 0.1M Tris-HCl Buffer (A). (Can be used for 5 days if kept refrigerated)F. Substrate solutionWeigh 11 mg of oxaloacetic acid and dissolve in 0.1M Tris-HCl buffer (A). Fill up to 50 ml with 0.1M Tris-HCl buffer (A) (Make a fresh solution for each use.)G. Enzyme solutionWeigh out Malate Dehydrogenase and dissolve in chilled 0.01M Phosphate Bufer containing 0.1% Triton X-100 (D). Enzyme solution should be prepared so that the value of AOD/minute becomes in the range of 0.025 ± 0.010.ProcedurePipette 2.0 ml of NADH solution (E) and 0.90 ml of Substrate solution (F) respectively into a quartz cell (d=10 mm) and keep at 25 + 0.5'℃ for 5 minutes. Then, pipete 0.10 ml of Enzyme solution (G) into the quartz cell and mix well immediately. Keep the reaction mixture at 25 ±0.5'C.Exaclly at 2 minutes and 5 minutes after the addition of Enzyme solution (G), measure the absorbances of the reaction mixture at 340 nm(A2 and A5).As a blank, pipette 0.01M Phosphate buffer (D) into another quartz cel (d=10 mm) instead of the Enzyme solution (G) and follow the same procedure described above (Ab2 and Ab5).CalculationMalate dehydrogenase activity (u/mg)=[(A2-A5)-(Ab2-Ab5)]/3*(1/6.22)*(n/0.1) ApplicationThis enzyme is used for the enzymatic determination of L-malate and gluamate oxalo-acetate transaminase(GOT)in clinical diagnosis... Read More |