4 - SPME Commercial Devices and Fibre Coatings

Abstract

This chapter focuses on the types and properties of the various commercially available solid-phase microextraction (SPME) coatings and devices. It provides a guide on how to select the appropriate fiber for application needs. There are several important criteria that are fundamental for the acceptance of SPME as an extraction technique. These criteria include ease of use and solvent-free extraction capability. The performance of SPME is critically dependent on the availability and selection of appropriate coating. The SPME fiber coating is primarily responsible for the extraction of analytes. Because SPME is capable of extracting a wide range of analytes from volatile to non-volatile and from polar to non-polar, it is important to have fiber coatings that can extract this range of analytes. To accomplish this, different coating types have been developed which enable extraction of a variety of analytes with enhanced selectivity. The reproducibility between fibers and the durability of the coatings are very important for SPME to be widely accepted as a qualitative and quantitative extraction technique. These two criteria allow the analyst to use one fiber for multiple extractions and to obtain similar results when multiple fibers are used. If the coating maintains its integrity, the repeated extractions of some samples should yield reproducible results. If the preparation of the fibers is reproducible, the new fiber should produce similar results compared to the replaced fiber.