Abstract
This thesis consists of two projects: (1) characterization of fish oil capsules using triglyceride (TG) as biological marker by direct injection electrospray ionization mass spectrometer (ESI-MS); (2) classification of bacterial causing food poison by magnetic nanoparticles concentration and liquid chromatography (LC) ESI-MS detection. The first project uses simple pretreatment coupled with direct injection to rapidly analyze fish oil capsules by sparing liquid chromatography. Furthermore, ESI-MS/MS was also exploited to characterize TG. A comprehensive TG list was established and used to infer the TG structure successfully. The method was successfully used to classify real fish oil capsules samples, which were consisted of two categories. One contains high concentration polyunsaturated fatty acid (PUFA) and the other contains low concentration PUFA. However, the three shark liver oil samples were failed to be detected by ESI-MS. Two of the three displayed unusual mass spectra and were presumably being adulterated. The second project pertains to rapidly detect bacterial. The Vancomycin-coupled magnetic nanoparticles which interact with Gram-positive bacterial only were prepared and used to concentrate bacterial from matrix. The concentrated bacterial were classified using protein as biological marker by LC ESI-MS. The dual results of molecular mass and retention time of proteins are advantageous to ubiquitous identification of bacterial.