| Summary: | A simple and efficient method called dispersive liquid–liquid microextraction based on solidification of floating organic droplets (DLLME-SFO) method coupled with gas chromatography flame ionization detector (GC-FID) was developed for the extraction of methylparaben (MP) in cosmetics. In the optimized DLLME-SFO method, a mixture of n-hexadecane (70 μL) as an extraction solvent and methanol (0.25 mL) as a disperser solvent was rapidly injected into a 5 mL sample solution (pH 6) containing 4 % (w/v) NaCl. After 4 minutes of centrifugation at 4000 rpm, the mixture was separated into two phases with the fine droplets of n-hexadecane floating at the top of the sample solution. Then, the test tube was placed in an ice bath for cooling and solidification purposes. The solidified extract was transferred into a small vial where it melted and injected into GC-FID system. The DLLME-SFO method gave a good linearity over the concentration range from 0.1-8 μg/mL with coefficient of estimation (r2) from 0.9996. The method also provides a low limit of detections (LODs) which is 0.0048 μg/mL. Methylparaben was detected in both samples at the concentration level of 0.06 μg/mL for sample 1 and 0.42 μg/mL for sample 2 respectively. © 2017, Malaysian Society of Analytical Sciences. All rights reserved.
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