Development of a Novel Ultrasound Vacuum-Assisted Headspace Solid-Phase Microextraction Approach for Determination of Solvent Residuals in Pharmaceuticals and Comparison with Traditional Headspace Solid-Phase Microextraction Method.

In this report, an ultrasonication and vacuum-assisted headspace solid-phase microextraction procedure followed by gas chromatography-flame ionization detection (UVA-HS-SPME-GC-FID) was proposed for direct extraction of solvent residuals, including benzene, toluene, ethyl benzene, m,p-xylene and o-xylene, in pharmaceutical matrices. A novel robust, reliable and durable nanocomposite solid-phase microextraction (SPME) fiber was prepared by layer-by-layer coating of 3-aminopropyltriethoxysilane-functionalized graphene on a stainless-steel wire. Then, the proposed fiber was used for headspace SPME and trapping of toluene as a residual solvent in solid penicillin, ampicillin and cefazolin vials followed by gas chromatography-flame ionization detection. UVA-HS-SPME-GC-FID achieves better validation parameters, including the limit of detection, limit of quantification, linearity, recovery and repeatability, in comparison with conventional HS-SPME-GC-FID. The UVA-HS-SPME-GC-FID strategy is very effective for quantitatively tracing volatile and semivolatile solvent residuals in various pharmaceutical drugs.