Enhanced peak responses due to solvent interactions in high-performance liquid chromatography

The liquid chromatography of a variety of pure compounds gave larger or smaller peak areas and heights (responses) depending on the injection solvent. The high-performance liquid chromatographic system was unchanged, with the pump, flow-rate, column, column temperatures and detector type and settings invariant for each comparison. Only the solvent for the analyte varied. For reversed-phase columns, the responses of each compound increased with the polarity of the solvent, and only compounds capable of forming intramolecular hydrogen bonds exhibited this effect. The retention time was not affected. Using normal-phase silica columns with steroids and essentially non-aqueous mobile phase, an analogous dependence of response on solvent was also found.