VYDAC Silica, produced by a novel process, was introduced by The Separations Group in the early 1980s. Starting with pure organosilicates, as opposed to the natural silica sols employed for other silica gels, the process results in very-high-purity metal-free spheroidal silica with well-controlled characteristics and a large pore size. Derivatized by the covalent surface addition of hydrocarbon chains of various lengths, VYDAC silica proves to be an ideal medium for high-performance reversed-phase chromatography of proteins, peptides, and other large molecules that had previously been difficult to separate by reversed-phase HPLC procedures.