Macromolecular Crowding Agents-Assisted Imprinted Polymers For Analysis Of Glycocholic Acid In Human Plasma And Urine

Glycocholic acid (GCA) is a newly identified biomarker for hepatocellular carcinoma (HCC) patients. In this study, a method based on macromolecular crowding strategy has been applied for preparation of a molecularly imprinted polymer (MIP), which possesses high adsorption capacity for GCA. Polymethyl methacrylate was used as a macromolecular crowding agent, N-(3-aminopropyl)-methacrylamide hydrochloride as a functional monomer and ethylene dimethacrylate as a cross-linker. The morphology and binding characteristics of MIP were assessed by scanning electron microscopy and absorption experiments. The MIP was used as an adsorbent material to separate GCA, and the molecularly imprinted solid-phase extraction (MISPE) was carefully optimized. The MISPE combined with high-performance liquid chromatographic analysis was successfully used to determine the GCA in plasma and urine samples. When spiked levels ranged from 0.2 to 20 μmol L^-1 , the recoveries were between 94.3 and 100.5%. As a proof of principle, this proposed method has been validated on a small subset of HCC patients (n = 10) and healthy volunteers (n = 10). The average GCA concentrations of HCC patients in plasma and urine were about 25 and 2.8 times than that of healthy volunteers. Copyright © 2016 John Wiley & Sons, Ltd.