in peptide mixtures, were the second choice. Zip-tips and spincolumns
removed a high amount of ampholytes, but a significant
number of peptides still could not be recovered. Another alternative
was the use of RP-HPLC. After optimization, it was possible to separate
peptide fractions from ampholytes using a monolithic column.
Peptides were observed just in the first five wells which demonstrated
the presence of mainly acidic peptides in SBIF. Collected fractions
were evaporated, redissolved, and assayed using OPAand ABTS
methods