Vortex-assisted liquid-liquid micro-extraction and high-performance liquid chromatography for a higher sensitivity methyl methacrylate determination in biological matrices

ABSTRACT:Avortex-assistedliquid–liquidmicro-extractioncoupledwithhigh-performanceliquidchromatography,withUV–vis,is proposed to pre-concentrate methyl methacrylate and to improve separation in biological matrices. The use of 1-octanol asextracting phase, its volume, the need for a dispersant agent, the agitation conditions and the cooling time before phaseseparation were evaluated. In optimum conditions, enrichment factors of 20 (±0.5) and enrichment recovery of 99% wereobtained. The straightforward association of this extraction pr ocess with the HPLC method, previously regulated by the Interna-tional Organization for Standardization, afforded a detection limit of 122 ng/mL and a quanti fication limit of 370 ng/mL. Thewithin-batch precision, relative standard deviation, was 3% for a sample with 1.49 μg/mL and 4% for a sample with 13.4 μg/mL.The results showed a between batch-prec ision of 21% for experiments performed on five different days, for a sample with aconcentration of 1.10 μg/mL in methyl methacrylate. Copyright © 2013 John Wiley & Sons, Ltd.Keywords: high-performance liquid chromatography; vortex-assisted liquid–liquid micro-extraction; methyl methacrylate; salivasamples