Take a 96-well enzyme-labeled plate and add reagents according to the following table. Tube number 1 2 3 4 5 6 7 8 standard protein solution (μl) distilled water (μl)

BCA reagent (μl)

Protein concentration (mg/ml) 0

twenty

200

0 1

19

200

0.025 2

18

200

0.05 4

16

200

0. 1 8

12

200

0.2 12

eight

200

0.3 16

four

200

0.4 20

200

0.5 After adding the above reagents, accurately suck 20μl of sample solution into the enzyme-labeled hole, add 200μl of BCA reagent, gently shake it, keep the temperature at 37℃ for 30-60min, cool it to room temperature, compare the color with blank as control, and draw a standard curve on the enzyme-labeled instrument at 590nm, with bovine serum albumin content as abscissa and absorbance as ordinate. Taking the blank of the standard curve as the control, the protein content of the sample was found out from the standard curve according to the absorption value of the sample.