Sorption characteristics of a wide pore, butylsiloxane-bonded silica sorbent for solid-phase extraction

Abstract

System maps for the calculation of sample processing conditions in solid-phase extraction (safe sampling volume and composition and volume of wash and elution solvents) are reported for aqueous solutions of methanol, 2-propanol, acetonitrile and tetrahydrofuran for a wide pore, butylsiloxane-bonded, silica sorbent. Solvent selectivity differences are largely governed by differences in the ease of cavity formation, hydrogen-bond acidity and phase ratio for the mobile and stationary phases. Compared to an octadecylsiloxane-bonded silica sorbent with a similar bonded phase density greater retention for the octadecylsiloxane-bonded sorbent results primarily from a more favorable cavity term and phase ratio with only small differences due to changes in selectivity for polar interactions.