Hi Sudheer, The units for the extinction coefficient are 1/(M*cm), which match the second value you mention. I would use that number. The calculation is (OD 280nm) / (extinction coefficient). This will give you a concentration in moles. You can multiply by 10^6 to get the concentration in micromoles, which is more likely to be in the right range for your protein.
Cheers, Irit On Jan 30, 2013, at 9:33 AM, Sudheer Sangeetham wrote: > Hello everyone > > I wanted to check my protein concentration based on its extinction > coefficient by using nanodrop rather than doing Bradford or Lowry methods. > I was checking the article in one article, The protein concentrations were > estimated using the extinction coefficient of 2.70 at 280 nm for a 1mg/ml > solution, but to the same protein in another article they determined the > concentration by giving 66350 /m/cm. If i want to check my protein > concentration by using nanodrop which value I should concern and how did > they get value of 2.7 ??? > > if anyone has idea please reply me > > Thanking you in advance > > Cheers > > -- > Sudheer Babu.S > Research Fellow > Institute of Biochemistry > Biological Research Center > Szeged,Hungary. > _______________________________________________ > Methods mailing list > [email protected] > http://www.bio.net/biomail/listinfo/methods _______________________________________________ Methods mailing list [email protected] http://www.bio.net/biomail/listinfo/methods
