Kit Components:

Product Introduction:

The Coomasylan G-250 dye is bound to the protein in an acidic solution so that the position of the dye's maximum absorption peak (Imax) changes from 465nm to 595nm, and the absorbance value A595 measured is proportional to the protein concentration within a certain concentration range. The protein concentration determined by Bradford method is not affected by the chemical substances in most samples. The concentration of merhydryl ethanol in the sample can be as high as 1M, and the concentration of dithithreitol can be as high as 5mM. However, affected by a slightly high concentration of detergent, it is necessary to ensure that the concentration of SDS is less than 0.1%, and that of Triton X-100 is less than 0.1%. The Tween 20, 60 and 80 were below 0.06%. For samples containing detergents, the BCA protein concentration assay kit produced by Solarbio is recommended.

Operation Instructions:

one. 1. Completely dissolve the protein standard, take 10ul, dilute to 250ul, and make the final concentration 0.2mg/ml. In what solution is the protein sample to be tested, the standard product should also be diluted with what solution. However, for simplicity, the standard can also be diluted with 0.9%NaCl or PBS. 2. Before use, please reverse and mix the 5×G250 dyeing solution 3-5 times, take 1ml of 5×G250 dyeing solution, add 4ml of double steaming water, and mix into 1×G250 dyeing solution. The 1×G250 dyeing solution can be stored at 4℃ for one week. 3. Add the standard product to the 96-well plate at the rate of 0,2,4,6,8,12,16,20 microliters, and add PBS diluent to make up to 20 microliters. 4. Dilute the sample appropriately (preferably do several gradients, such as 2 times, 4 times, 8 times dilution), and add 20 microliters to the sample hole of the 96-well plate. Due to the error of the pipette when taking a small amount, the point in front of the standard line may not be very accurate, so as far as possible, let the sample point fall 1/2 behind the standard line. 5. Add 200 microliters of diluted 1×G250 dyeing solution to each hole and leave for 3-5 minutes at room temperature. 6. The absorbance of A595, or other wavelengths between 560-610nm, is determined with an enzyme marker. 7. Calculate the protein concentration in the sample according to the standard curve. two. Spectrophotometer If there is no enzyme label, the dyeing reaction can be carried out in the centrifuge tube, and the reaction liquid is mixed and added to the colorimetric dish, and the light absorption value is determined by spectrophotometer. The steps are as follows: 1. Take eight (or more) clean 10ml centrifuge tubes and mark them. 2. Add 100ulBSA to PBS 2.4ml and dilute until the final concentration is 0.2mg/ml. 3. Before using the 5×G250 dyeing solution, please reverse and mix it for 3-5 times. Take 10ml of the 5×G250 dyeing solution, add 40ml of double steaming water, and mix it into 1×G250 dyeing solution, which can be stored at 4℃ for one week.

5. OD value was measured after reaction for 3 minutes. For the accuracy of the experiment, a tube of dyeing solution can be added every 2 minutes, and the OD value of a tube can be measured every 2 minutes. The following table:

Note：Product information may be optimized and upgraded. Please refer to the actual label information for accuracy.