The study of the liquid chromatographic separation of enantiomers on immobilized bovine serum albumin

The equilibrium adsorption data of enantiomers on immobilized bovine serum albumin (BSA) exhibit bimodal retention — enantioselective and nonselective interactions. The two site bilangmuir adsorption isotherm accounts well for these interactions. Incorporating this information into the equilibrium dispersive model of chromatography, the overloaded elution band profiles for both pure enantiomers and binary mixtures of various compositions are simulated and compared to the experimental profiles. The agreement is excellent. Knowing that the band profiles can be accurately calculated, the operating conditions (the sample size, the reduced velocity and the retention parameters) are optimized in order to maximize the production rate. Following the extraction of appropriate preliminary experimental data, a maximum search method is employed saving a considerable amount of time over empirical methods, especially when examining more than one parameter. When recovery yields less than 99% are tolerated, allowing overlapping bands, a dramatic increase in the production rate is observed, compared to the touching bands condition. Also, the immobilization of bovine serum albumin on an anion exchanger by frontal analysis proves to be both a simple and an inexpensive method for generating an enantioselective column. The separation of enantiomers on these columns is investigated under analytical and overloaded conditions.