Protein Separations on Octyl and Diphenyl Bonded Phases

Abstract

Two new packing materials specifically designed to handle high performance liquid chromatographic separations of proteins and peptides have been made. These are built on a 300 A pore silica gel to allow access of large molecular weight species, and are exhaustively bonded, first with an octyl or a diphenyl silane and final end-capping with trimethylsilyl groups. The media are called Protesil 300 Octyl and Protesil 300 Diphenyl. Their unique selectivity is shown with various samples of dipeptides and proteins. The Octyl phase has specific affinities for alkyl functionalities, the Diphenyl phase has specific affinities for aromatic functionalities. Loading and mass recovery studies have been done on these media to show their capabilities under the elution conditions shown in the various separations. Comments regarding their correct use have also been made.