Materials:

• BSA (bovine serum albumin) standard solution stored with a concentration of 1.4 mg/ml
• Bradford reagent (dye-binding reagent)
• Test samples containing protein
• 96 well Microplate
• Spectrophotometer

Procedure:

• Prepare the BSA standard solutions of different concentrations (e.g., 0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6 µg/µL) by diluting the BSA stock solution with distilled water as follows.
  
  BSA standard preparation for working concentration 1mg/ml
• 45 µL (BSA 1.4 mg/ml in DDW) +18 µL DDW

Final BSA Concentration µg/µL	Volume BSA from 1 mg/ml (µL)	Volume DDW (µL)
0	0	25
0.05	1.25	23.75
0.1	2.5	22.5
0.2	5	20
0.3	7.5	17.5
0.4	10	15
0.5	12.5	12.5
0.6	15	10

• Add 10 µL of each BSA standard solution to the 96-well microplate in duplicates.
• Lysates diluted 1:10 in DDW, e.g., 3 µL Lysate + 27 µL DDW.
• Add 10 µL of each diluted lysate in duplicates.
• Add 150 µL of Bradford reagent using a multi-channel pipette.
• Measure Immediately OD at 595 nm using a spectrophotometer.

PRO TIP: Practice proper pipetting technique as it is clearly presented here.