The selective response of a templated polymer for the cationic drug pentamidine: implications from molecular simulations and experimental data

Abstract

In this paper, we present an analysis of the surface modifications responsible for the selectivity of a new imprinted sorbent produced for the isolation of pentamidine cations. We examined the polymers formed from acrylic acid as the monomer, ethylene glycol dimethacrylate as the cross-linker and 4-methoxybenzamidine as the template. A molecular simulation showed the creation of the complex surface system joined with the protonation of the template molecule in a prepolymerization complex. Polymer cavity models enabled the adsorption process to be theoretically simulated, and the binding energies of the structurally related analytes were used as a measure of sorbent selectivity. An applicative analytical scheme for the determination of pentamidine in human urine was used to prove the utility of the templated polymer matrix. The analytical strategy involved separating the pentamidine through a molecularly imprinted solid phase extraction process and detecting it using high-performance liquid chromatography coupled with ultra-violet spectrophotometry. The experimental results demonstrated a good agreement with the theoretical evaluations.