Simultaneous Determination of Zoalene and Its Metabolite in Chicken Muscle and Liver by SPE and UPLC-MS-MS

Lipoproteins, especially high-density lipoproteins (HDL), very low-density lipoproteins (VLDL) and small, dense low-density lipoprotein (sdLDL), are believed to play an important role in the development of atherosclerosis. In this work, a simple, selective and sensitive method for the simultaneous monitoring of these lipoproteins in human serum using microchip capillary electrophoresis was developed. Gold nanoparticles were used as an additive to the running buffer to obtain the absolute separation of the lipoproteins. Under optimised conditions, the linear ranges of large buoyant low-density lipoproteins, sdLDL, VLDL and HDL were 10-800, 10-800, 40-1,000 and 20-800 mu g L-1, and their limits of detection were 5, 5, 15 and 8 mu g L-1, respectively. The intraassay and interassay relative standard deviation of lipoprotein peak areas were in the range of 3.8-7.4%. For practical application, variations in the serum lipoprotein of coronary heart disease patients were monitored by microchip-based CE. The results showed that the method was applicable for routine clinical use and allowed the rapid detection of different lipoprotein classes as well as their subclasses, thus greatly improving the analysis of atherosclerotic risk factors.