Surface characterization of commercial fibers for solid-phase microextraction and related problems in their application

The surfaces of commercially available polydimethylsiloxane (PDMS) and Carb oxen-PDMS fibers for solid-phase microextraction (SPME) were investigated b y optical and electron microscopy, Damage to the coating as well as contami nation of new fibers and a highly variable number of pores in Carboxen-PDMS coatings were observed, Together with the contamination of the fibers duri ng their use with metallic particles originating from the SPME fiber holder they are possible explanations for the problems encountered in the analysi s of organolead, organotin and organosulfur compounds, such as artifact for mation and low repeatability.