A Novel Molecularly Imprinted Polymer for the Solid-Phase Extraction of Tanshinones from Serum

Abstract

A molecularly imprinted polymer (MIP) was synthesized by precipitation polymerization with tanshinone IIA as the template and used as an adsorbent for solid-phase extraction (SPE). A simulation was employed to predict the most suitable polymerization solvent, the functional monomer, and the molar ratio of template to monomer. The obtained imprinted materials were evaluated by transmission electron microscopy, scanning electron microscopy, rebinding experiments, exhibiting good morphology, and high binding to tanshinone IIA. Compared with nonimprinted polymers, the imprinted material exhibited a higher sorption capacity, up to 34.09 µmol g⁻¹, and better selectivity for tanshinone IIA and its structural analogs. The imprinted polymer was successfully employed for SPE coupled with high-performance liquid chromatography for the determination of tanshinone IIA, cryptotanshinone, and tanshinone I in fortified serum. The mean recoveries were between 91.5% and 95.1% with relative standard deviations less than 4.9%. These results demonstrate a highly selective isolation and determination of tanshinones.

Keywords:

• High-performance liquid chromatography
• Molecularly imprinted polymer
• Precipitation polymerization
• Solid-phase extraction
• Tanshinone IIA

Notes

Note: Binding properties were determined by adding 5.0 mL chloroform with 2.0 mmolL⁻¹ tanshinone IIA in 20 mg polymer for 3.0 h. EGDMA = ethylene glycol dimethacrylate; TRIM = trimethylolpropane trimethacrylate.

^aThe molar ratio refers to template:monomer:crosslinker.