Selective Adsorption of Berberine Hydrochloride Using Molecularly Imprinted Polymers with Modified Rosin as Cross-linker

Abstract

Molecularly imprinted polymers containing phenanthrene skeleton were prepared via suspension polymerization with ethylene glycol maleic rosinate acrylate (EGMRA) as a cross-linker, berberine hydrochloride as the template and methacrylic acid as the functional monomer. The binding characteristics of the molecularly imprinted polymers and their templates were evaluated via equilibrium binding, whereas those of berberine hydrochloride on molecularly imprinted polymers were evaluated via Scatchard analysis. The adsorption energy was measured via microcalorimetry, whereas the selective recognition of molecularly imprinted polymers was investigated through high-performance liquid chromatography. Scatchard plot analysis reveals the formation of two types of binding sites in the molecularly imprinted polymers, with their respective equilibrium dissociation constants at K_d1 = 0.0204 and K_d2 = 0.0507 mmol·L^-1. The heat flow curve exhibits an endothermic peak and two relatively weak exothermic peaks for the adsorption. Selective adsorption results demonstrate the high affinity and berberine hydrochloride selectivity of the molecularly imprinted polymers.