1. The problem statement, all variables and given/known data I am to calculate the molar extinction coefficient for Bovine serum albumin 2. Relevant equations ε = (nW×5500) + (nY×1490) + (nC×125) for coefficients around 280nm 3. The attempt at a solution I know how to solve this by adding up the tryptophan, tyrosine, and cytosine for the peptide sequence of BSA, but for the lab I am running we are testing absorbance at 595 nm, not 280nm. Also I know that the Practical Handbook of Biochemistry and Molecular Biology cites most extinction coefficients at 280. Can I still use my calculation for the formula that is supposed to be at 280nm. When I do the math I get: (3*5500) + (21*1490) + ( 34*125) = 52040 M ^-1 cm^ -1 this seems too high though, as most sources I'm finding say the extinction coefficent should be around 44,000. I used an amino acid sequence my prof gave me.