Study On Fatty Acids Metabolism Related To Diabetic Nephropathy

Based on the technique of capillary gas chromatography-flame ionization detector (GC-FID), this dissertation established simultaneous quantitation methods with and without derivatization for free fatty acids in human plasma and described the application of derivatization-free method to the evaluation of free fatty acid levels in plasma of diabetic nephropathy patients during course of treatment. Develoment of thess analytical methods render useful tools for illuminating diabetic nephropathy mechanism and improving evaluation of drug proficiency.A derivatized GC-FID method was first developed as an improvement of well recognized standardized method. Fatty acids fail to separate on conventional GC columns due to high boiling points, and therefore methylation was adopted during sample preparation transforming fatty acids into fatty acid methyl esters, which were suitable for GC-FID detection. A derivatizaiton-free GC-FID method was then established employing a strongly polar capillary column, separating free fatty acids direcrtly, where the simplified sample pre-treatment procedure managed to avoid extra error and quantitate short chain free fatty acids.Above two methods managed to quantitate common free fatty acids in human plasma. The derivatized GC-FID method employed pentadecanoic acid as internal standard, while derivatization-free GC-FID mehod employed heptadcanoic acid. Method validations were carried out afterwards to assess recovery, intra-day precision, inter-day precision, sensitivity, stability, and linear range, etc.Evaluation of fifteen common free fatty acids in human plasma was achieved via derivatization-free GC-FID quantitation, where data analysis was therefore performed on clinical samples. From analysis of longitude data during course of treatment in diabetic nephropathy patients, the trend and biological significance were discussed. It revealed important relationship between diabetic nephropathy and free fatty acids metabolism, providing methodology for research of diabetic nephropathy mechanism and clinical evaluation of medicine proficiency.