Application of a novel sol-gel polydimethylsiloxane-poly(vinyl alcohol) solid-phase microextraction fiber for gas chromatographic determination of pesticide residues in herbal infusions.

A simple and environmentally friendly methodology for headspace solid-phase microextraction (HS-SPME) using a new fiber coated with polydimethylsiloxane-poly(vinyl alcohol) (PDMS/PVA) is reported for the trace determination of organochlorine (OCP) and organophosphorus (OPP) pesticides in herbal infusions of Passiflora L. by GC-ECD. The capacity of the PDMS/PVA coating for the pesticides was compared to that of commercial PDMS fibers, with advantageous results.

Preparation and characterization of polydimethylsiloxane/poly(vinylalcohol) coated solid phase microextraction fibers using sol-gel technology.

The applicability of a composite composed of polydimethylsiloxane (PDMS) and poly(vinyl alcohol) (PDMS/PVA) as coating sorbent for SPME fibers is demonstrated here. Fused silica (FS) fibers were coated with PDMS/PVA composite through a sol-gel process, using methyltrimethoxysilane as reticulating agent. The chemical and physical properties of the sol-gel PDMS/PVA composite were determined by infrared spectroscopy and thermogravimetric analysis.