Protein Detection Methods
Aug 28, 2022
Source: Cainiu Health
Dr. Yang Shuwen
Introduction
If protein detection is required, the biuret method can be used. Specifically, 12 test tubes are each filled with standard protein solution and diluted with distilled water to a final volume of 1 mL; then, 4 mL of biuret reagent is added to each tube. After thorough mixing and allowing the mixture to stand, absorbance is measured at 540 nm to construct a standard curve, which is subsequently used to determine the protein concentration in the sample.
If protein detection is required, the biuret method can be employed. The procedure is as follows:
1. Prepare 12 test tubes, divided into two groups. Add varying volumes (0, 0.2, 0.4, 0.6, 0.8, and 1.0 mL) of standard protein solution to each tube. Then add distilled water to bring the total volume in each tube to 1 mL, followed by the addition of 4 mL of biuret reagent.
2. Thoroughly mix the contents of each tube, then allow them to stand at room temperature (20–25°C) for 30 minutes. Subsequently, measure the absorbance of each tube at a wavelength of 540 nm.
3. Use the tube containing no protein solution as the blank control. Calculate the average absorbance values from the two groups, and construct a standard curve with protein concentration (μg/mL) on the x-axis and absorbance on the y-axis.
4. Repeat the same procedure using 2–3 additional test tubes to determine the protein concentration in the sample.
