Information on drug-protein interactions and free drug fractions could help scientists better understand the adsorption, distribution, metabolism and excretion of drugs in the human body. This dissertation uses various affinity chromatographic techniques, such as frontal analysis, peak profiling and chromatographic immunoassays to examine drug-protein systems.

The first part of this dissertation involves the detection of heterogeneity in biomolecular interactions by frontal analysis. It was found that double-reciprocal plots could be used more easily than traditional isotherm plots for the initial detection of binding site heterogeneity. The factors influencing heterogeneity detection were studied and evaluated. The experimental conditions needed to observe heterogeneity were also determined.

The second part of this dissertation examines the kinetics of drug-protein binding by peak profiling method. The elution profile of a drug and a nonretained species on an HSA column and control column were analyzed. This approach was expanded to make it suitable for the study of multi-site interactions. Nonspecific binding of a drug to a support was corrected in each study. Peak profiling was found to provide a high-throughput and accurate method for kinetics studies in pharmaceutical research.

The last part of this dissertation explores the development of a reverse displacement immunoassay for the analysis of free phenytoin fractions. This approach used a microcolumn containing an immobilized drug analogue and near-infrared fluorescent F_ab fragment labels. The free fraction of phenytoin in serum was measured by this method.