Bio-Rad protein assay protocol

   - Protein purification
     - Introduction
     - Step-by-Step
     - Common sense
     - Protocols
       - Stock solutions
       - Cell disruption
       - Protamin sulphate treatment
       - Analytical AM cut
       - Preparative AM cut
       - Protein precipitation by AM
       - Protein recovery from AM
       - Solubility of expression
       - Solubility of expression
       - Protein concentration
       - Protein concentration
     - Charts & Tables
     - Appendix
   - Crystallisation

   - Chemistry
   - Protein
   - Peptide
   - Amino Acids

- CCP4BB

Protocols and tips in protein purification or How to purify protein in one day.

Sveta's adaptation of the Bio-Rad micro assay procedure

Place 1-20 µl of protein solution, containing approximately 1-10 µg of protein into a plastic cuvette (1.6 ml volume).
1.Add 0.8 ml of milliQ water and 0.2 ml of Bio-Rad Dye Reagent Concentrate.
Seal cuvette with parafilm and mix carefully by tipping upside down and right way up again.
Measure OD₅₉₅. It should be between 0.1 and 0.7.
If readings are higher, dilute protein solution or take smaller volume, if they are lower, increase volume of protein solution taken for test and decrease the volume of water accordingly to keep total volume of test within 1 ml.
Calculate Protein concentration using formula:

(OD₅₉₅ x 15)/(volume of protein (µl)) = protein concentration (mg/ml).