PolymerXâ„¢ RP-1 consists of microporous (100 Ã…) polystyrene divinylbenzene (PSDVB), which is inherently similar to reversed phase chemistries, displaying similar selectivity characteristics as C18-bonded silica columns. Because bare PSDVB shows similar selectivity to a C18 column, no surface ligands are bonded to the polymer. In turn, this means no phase collapse under high aqueous conditions, no bonded phase bleed at high temperature, and no phase hydrolysis.