Retention behaviors of polybutadiene-coated titania and comparison to bonded phase based on linear solvation energy relationships

The retention behaviors of polybutadiene-coated titania stationary phase (PBD-TiO2) are investigated by the use of linear solvation energy relationships (LSERs) of 21 solutes. The logarithmic capacity factors measured on PBD-TiO2 (log k' (PBD-TiO2)) in a methanol-water (80:20, v/v) mobile versus the solutes' four interaction descriptors, the McGowan characteristic molar volume (V-x), dipolarity/polarizability (pi(2)*), effective or overall hydrogen bond donor acidity (Sigma alpha(2)(H)) and hydrogen bond acceptor basicity (Sigma beta(2)(H)) are analyzed by multiple regression analysis and compared to conventional bonded reversed stationary phase. We find that PBD-TiO2 is very similar to conventional bonded reversed stationary phase. The descriptors, V-x, pi(2)* and Sigma beta(2)(H) are the most important parameters governing the retention, as they represent more than 96.62% of the log k' variation. Finally, we come to the conclusion that the retention of PBD-TiO2 is a partition mechanism.