Hi, If you have the correct (experimentally-determined) extinction coefficients, the accuracy is usually very good. Often, however, people use calculated extinction coefficients, which can be off (usually not by more than 25%, so still OK for many purposes).
One of the best practical ways to experimentally determine accurate extinction coefficients is the Edelhoch method. You can read about it here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2143013/pdf/8563639.pdf -Tom ----------------------- Thomas Cleveland NIST Center for Neutron Research Gaithersburg, MD On Sun, Aug 20, 2017 at 10:14 AM, anita patil < 0000153960d6533c-dmarc-requ...@jiscmail.ac.uk> wrote: > > > > > Dear Members, > How well is extinction coefficient based protein concentration measurement > accuracy established. It seems that several monograph based protein HPLC > assays use 214 for the same. How accurate are extinction coefficients for > the same proteins. Is there any consensus if which one is more accurate for > estimation. Some glycoprotein monographs use extinction coefficients. > > Thanks ahead > > Anita Ramdas Patil, Ph.D. > Group Leader, ADL > Wockhardt Research Center, > Aurangabad, > INDIA Email: patilramdasan...@yahoo.com > Mobile# 91+8980217260 > > >
