A280 - (Feb/21/2005 )

Hi, I would like to know how to estimate protein concentration by using A280 measure. Does it use any protein standard or calibration curve?
Thank you in advance!!!!!

estimation by A280 is not an accurate method beacuse it is based on the absorbance of the unmodified protein and depends on the extinction coefficient. you can use is only if you know the extinction coefficient of you protein. you will have to calculate it by using a range of protein concentrations. theoretically determined coefficients (from the sequence) quite often deviates from the observed value.

Sharath.B
Research Fellow
National Chemical Laboratory,
India