Synthesis, characterization and application of spherical and uniform molecularly imprinted polymeric nanobeads as efficient sorbent for selective extraction of rosmarinic acid from plant matrix

Abstract

This work reports the synthesis and application of uniform and spherical molecularly imprinted polymeric (MIP) nanobeads for selective and efficient preconcentration of Rosmarinic acid (RA). The as-prepared RA MIP nanobeads were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) techniques. As analyzed, nano-sized particles of MIP with spherical and uniform shape and the average size of 88 nm were synthesized. The prepared MIP nanobeads were used in an ultrasonic-assisted dispersive solid phase extraction approach (UA-DSPE) for extraction of RA as a natural antioxidant specie from the extract of Salvia Officinalis leaves. In UA-DSPE process, the RA content of the samples was determined using high-performance liquid chromatography (HPLC). The highest recovery percentage (>90%) was observed after loading of RA solution (pH 5.7) and after elution with 3 mL of acetic acid aqueous solution, followed by 6 min sonication. The selectivity studies demonstrated a selective and high affinity binding of the template molecule (i.e. RA) toward MIP sorbent compared to other compounds such as gallic acid, caffeic acid, and pyrocatechol.