.beta.-Cyclodextrin-bonded silica for direct injection analysis of drug enantiomers in serum by liquid chromatography

Abstract

A new beta-cyclodextrin (CD) bonded silica has been designed for direct injection analysis of drug enantiomers in serum for liquid chromatography. The new beta-CD bonded silica is synthesized by three steps: introduction of a 3-glycidoxypropyl phase, introduction of a beta-CD carbamate-bonded phase, and hydrolysis of the oxirane ring to a diol phase. Although the recovery of serum proteins from only a beta-CD bonded silica (having no diol phase) was poor, they were completely recovered from a mixed functional silica having beta-CD and diol phases. Direct injection analysis of drug enantiomers in serum can be attained with the mixed functional silica support over the eluent pH range of 3-7. The recovery of racemic drugs from serum was almost 100%.