Peptide Conc @215 and 225nm? - (Sep/04/2012 )

Hi Guys,

I have a peptide with one tyrosine and no Try or Cys.
I used the nanodrop previously but it seems that the accuracy wasn't good to measure the affinity using ITC.
-I want to measure the concentration using the Absorbance at 215 nm and 225nm then use this equation: ug/ml=144*(215-225)
So I need to know the concentration by uM. How can I convert to molar concentation. The MWt of the peptide is about 3237.3 Da.
- The other question related to 215/225 I think the abo should be less than 1.5 to be accurate, is it right.

Thank you so much

This might be of some help to you, I use it all the time. Promega Biomath Protein Molar Conversions Calculator