Determination of releasing plasticizers from dental floss using ultrasound-assisted extraction-dispersive liquid-liquid microextraction followed by gas chromatography-flame ionization detector

Recently, the wide existence of phthalate esters in healthcare products has attracted great attention from scientists due to their negative effects on human health. As a result, the current study was carried out to determine the presence of some plasticizers in dental floss such as di-n-butyl phthalate, diethyl phthalate, di-2-ethylhexyl phthalate, di-iso-butyl phthalate, and bis-2-ethylhexyl adipate. The studied analytes were extracted from dental floss by an ultrasound-assisted extraction procedure and then enriched by a dispersive liquid-liquid microextraction method. For this purpose, a piece of dental floss was immersed in acetonitrile under sonication to extract the analytes. Then, the acetonitrile phase containing the extracted analytes was mixed with a proper extraction solvent at mu L-level and injected into sodium chloride solution. The extracted analytes were determined by gas chromatography-flame ionization detector and gas chromatography-mass spectrometry. Under the best extraction conditions, limits of detection and quantification were found in the ranges 0.20-0.33 and 0.67-1.1 mu g/L in solution and 0.06-0.10 and 0.19-0.33 mu g g-1 in dental floss, respectively. Relative standard deviations were in the ranges 4.0-6.5% and 5.1-7.9% for intra-day and inter-day precisions for five replicates at 60 mu g/L of each analyte. Enrichment factors and extraction recoveries of the analytes ranged from 350 to 460 and 70-92%, respectively.