An Improved Automatic Analyzer for Organic Compounds in Water Based on Headspace Solid Phase Microextraction (SPME) Coupled to Gas Chromatography

Abstract

Recently we introduced a first prototype system for quasi-continuous analysis of organic compounds in water based on SPME coupled to GC. The system showed some disadvantages with regard to calibration and sample preparation, for example in pH adjustment. These limitations were overcome in a complete redesign of the instrumental setup (Grote et al, 1999). The instrumental set-up was now based on a stopped-flow approach. Moreover, all analytical steps (sampling, extraction and analysis) were completely automated. Finally, remote control of the analyzer was possible. The system was tested with industrial waste water (a very difficult matrix) using direct SPME (i.e., insertion of the fiber Into the aqueous phase). However, extensive testing of the automated analyzer in the field all revealed some shortcomings. As a result of the aggressive waste water matrix, the performance of the extraction fiber decreased steadily during 1–2 weeks of automated operation.