POLYMERIC MEMBRANE DEVICES AND AUTOMATION - DESIGNS FOR INNOVATIVE STUDY IN MICROSCALE ANALYTICAL TECHNIQUES FOR ENVIRONMENTAL ANALYSIS

Abstract

This dissertation presents the development of miniaturized sample preparation techniques and procedures for environmental analysis. Various applications of the developed techniques are also demonstrated. The miniaturized sample preparation approaches under study comprise of electromembrane extraction (EME), in-syringe dynamic liquid-phase microextraction (LPME) and two-phase LPME. The main focus of this work was to design polymeric membrane devices suitable for convenient sample pretreatment and to incorporate automation into the miniaturized sample preparation procedures. Novel designs of membrane envelopes and membrane sacs were described for the first time in this work. Further steps were also taken to design and implement fully-automated LPME-gas chromatography-mass spectrometric (GC-MS) systems, which allowed multiple and consecutive experiments to be carried out sequentially, without any human intervention between experiments. The methodologies developed were highly efficient and convenient, which served to address the increasing demand for simplicity and automation in the sample preparation field. In EME, the hitherto unprecedented simultaneous extraction of more than a single class of analytes (acidic, basic and neutral compounds) in a single extraction was also accomplished.