Covalent organic nanospheres modified magnetic nanoparticles for extraction of blood lipid regulators in water samples.

Covalent organic nanospheres are new kind of nanospherical polymer with large specific surface area, uniform morphology, and excellent chemical and thermal stability. This material can be fabricated by a facile and rapid room temperature solution-phase strategy. In this work, magnetic nanoparticles were attached to the surface of covalent organic nanospheres, and the obtained composites were used for the extraction of blood lipid regulators such as clofibrate and fenofibrate. These composites were characterized with Fourier-transformed infrared spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. Several parameters that might affect the extraction efficiency including acetonitrile content, pH value, extraction time, and sample volume were investigated. Under optimum conditions, the proposed analytical method showed high extraction efficiency toward clofibrate and fenofibrate with enrichment factors between 60 and 83. This method exhibited outstanding analytical performance with wide linear range and excellent reproducibility and had low limits of detection in the range of 0.02-0.03 ng/mL. This method was also applied to the detection of clofibrate and fenofibrate in lake water samples, and good recoveries in the range of 92.6-112.6% was obtained.