Factorial experimental design optimization of solid phase microextraction (SPME) conditions for analysis of butylated hydroxytoluene (BHT) in bottled water

Abstract

BHT is an antioxidant utilized as additive in some foods and in packaging plastics, and its presence in bottled mineral water is possible due to its migration from bottle walls to the contents. A factorial experimental design was utilized to obtain the optimum values for the main operational parameters in the analysis of butylated hydroxytoluene (BHT) in bottled water using headspace and direct solid-phase microextraction (SPME) in the pre-concentration step. The parameters optimized were sample pH, temperature and ionic strength. The separation, detection and quantitation of the extracts were performed by gas chromatography coupled to mass spectrometry. Preliminary experiments were made to select the best fiber for the extraction procedure. Polydimethylsiloxane (PDMS) fibers were selected, and the optimized methodology was successfully applied to the extraction and quantitation of BHT in real samples of mineral and mineralized bottled water.