Extraction of methylparaben in cosmetics using dispersive liquid-liquid microextraction based on solidification of floating organic drop coupled with gas chromatography flame ionization detector; [Pengekstrakan metilparaben dalam kosmetik menggunakan pengekstrakan mikro cecair-cecair serakan berdasarkan pemejalan organik terampai berganding dengan kromatografi gas pengesan nyala pengionan]

• Published in: Malaysian Journal of Analytical Sciences
• Main Author: Shukri D.S.M.; Hamedan N.A.; Hussin N.S.; Nawawi W.I.
• Format: Article
• Language: English
• Published: Malaysian Society of Analytical Sciences 2017
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85039756553&doi=10.17576%2fmjas-2017-2106-10&partnerID=40&md5=6ee59c566f9c4d933d69ec22ba063a86

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.