High performance liquid chromatographic selectivity

Abstract

Chromatography is one of the most powerful techniques available in the analytic chemist's arsenal to identify and measure components in complex sample matrixes. An elementary description of chromatography would be a technique to separate analytes based on chemical or physical differences, often containing two or more "environments" that each analyte has an affinity towards. If chosen wisely, the analytes needing to be separated will partition in each environment and the result ends with them being either separated in time or space depending on the chromatographic technique used. In the field of HPLC, the most used separation mode is reverse-phase and is estimated to represent 65-90% of all separations. The scope, versatility, simplicity, and durability have been all key reasons for the success of reverse-phase chromatography. Chromatographic selectivity can be influenced by a number of different factors and is the core result all separation scientists seek when they are doing chromatography. This thesis seeks to investigate the fundamentals of reverse phase separations, variables of stationary phase and mobile phase, and the use of detectors for special selectivity. Reverse phase selectivity and separations are often done with C18 columns and the association of hydrophobic separation and its relationship with selectivity for reverse phase separations is the standard that most chromatographers use to evaluate stationary phases. This thesis will investigate and evaluate if this approach is fundamentally correct and/or if there is a better way to conceptualise stationary phase selectivity. Different models in both understanding and prediction are reviewed and future studies are suggested.

Date of Award	2016
Original language	English