DEVELOPMENT AND APPLICATION OF MINIATURIZED SAMPLE PREPARATION TECHNIQUES COMBINED WITH GAS CHROMATOGRAPHY-MASS SPECTROMETRY IN ENVIRONMENTAL ANALYSIS

Abstract

This dissertation presents the development and application of miniaturized sample preparation techniques for environmental analysis. For sorbent-based microextraction, the applicability and feasibility of graphene or modified graphene as sorbent was investigated and evaluated. The possibility of graphene serving as sorbent was first explored in micro-solid-phase extraction. To further investigate its extraction capability, well-dispersed graphene was applied in a variation of solid-phase microextraction (SPME), which was assembled with a commercially-available plunger-in-needle microsyringe, in which the plunger was coated with graphene. With this setup, a ready-made SPME device resembling a commercial system, was conveniently devised. A liquid-phase microextraction (LPME) approach was developed: plunger-in-needle LPME, based on similar concept as plunger-in-needle SPME. A hydrofluoric acid-etched stainless steel plunger was used as organic solvent holder and support. The aforementioned miniaturized and environmentally friendly sample preparation methods were demonstrated to be simple, fast and cost-effective for the analysis of organic pollutants from environmental aqueous samples.