Synthesis and characterization of stable polymer-coated C8 stationary phase with high durability under extreme pH conditions for high-performance liquid chromatography

A highly chemically stable polymer-coated silica-based C-8 stationary phase was developed by combining modification with octyl groups and a polymer coating technology. The stationary phase was prepared by the following procedure: (1) introduction of octyl groups to the silica surface-, (2) coating the C-8 silica with a silicone polymer. Si-29 solid-state NMR spectra indicated that a silicone polymer reacted not only with residual silanol groups on the silica surface, but with those generated from silanes used for the introduction of octyl groups. Column durability was evaluated with an acidic mobile phase (60 degrees C, pH 1) and a basic mobile phase (50 degrees C, pH 10) in accelerated damaging conditions. The C-8 phase showed a high durability under both conditions. (c) 2004 Elsevier B.V. All rights reserved.