Porous silver coating fiber for rapidly screening organotin compounds by solid phase microextraction coupled with surface enhanced Raman spectroscopy

Abstract

Preclinical research reveals the risk of organotin compounds (OTCs) as potent endocrine disruptors, immunotoxicants and environmental obesogens for mammals. OTCs are commercial antifungal agents which are found extensively in clothing, female hygiene products and childcare articles. OTCs have been listed as restricted chemicals by REACH Regulation (Annex XVII). Here, a hyphenated method combining surface enhanced Raman spectroscopy (SERS) with solid phase microextraction (SPME) is proposed for rapid screening of OTCs. A porous Ag layer was synthesized in situ and served as the SERS-active SPME coating for adsorption. The SERS spectra of trimethyltin chloride, tributyltin chloride and triphenyltin chloride were investigated, the bands at 554 cm⁻¹, 1410 cm⁻¹ and 999 cm⁻¹, respectively, being selected as the characteristic peaks for quantitative determination. The extraction conditions were optimized. The good stability and uniformity of porous Ag fibers insure a high enhancement factor of 9.1 × 10⁵ and low LOD of 0.2 ppb for triphenyltin chloride. The proposed method was successfully applied to identify a mixture of OTCs in a textile matrix with satisfactory results.