title: Quantitative analysis of methyl parathion pesticides in a polydimethylsiloxane microfluidic channel using confocal surface-enhanced Raman spectroscopy.
abstract: A fast and ultra-sensitive trace analysis of methyl parathion pesticides in a polydimethylsiloxane (PDMS) microfluidic channel was investigated using confocal surface-enhanced Raman spectroscopy (SERS). A three-dimensional PDMS-based passive micromixer was fabricated for this purpose. This PDMS micromixer showed a high mixing efficiency because a strong chaotic advection was developed by the simultaneous vertical and transverse dispersion of the confluent streams. The confocal SERS signal was measured after methyl parathion pesticides were effectively adsorbed onto silver nanoparticles while flowing along the upper and lower alligator-teeth-shaped PDMS channel. A quantitative analysis of the methyl parathion pesticides was performed based on the measured peak height at 1246 cm-1. Our method has a detection limit of 0.1 ppm. This value satisfies the requirement recommended by the Collaborative International Pesticides Analytical Council (CIPAC) for the determination of methyl parathion in pesticide formulations. This study demonstrates the feasibility of using confocal SERS for the highly sensitive detection of methyl parathion pesticides in a PDMS microfluidic channel.
authors.affiliation: Department of Applied Chemistry, Hanyang University, Ansan 426-791, South Korea.
authors.forename: Donghoon
authors.initials: D
authors.lastname: Lee
authors.forename: Sangyeop
authors.initials: S
authors.lastname: Lee
authors.forename: Gi Hun
authors.initials: GH
authors.lastname: Seong
authors.forename: Jaebum
authors.initials: J
authors.lastname: Choo
authors.forename: Eun Kyu
authors.initials: EK
authors.lastname: Lee
authors.forename: Dae-Gab
authors.initials: DG
authors.lastname: Gweon
authors.forename: Sanghoon
authors.initials: S
authors.lastname: Lee
mesh_terms: D002138:Calibration; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D008743:Methyl Parathion / Q000032:analysis*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D018613:Microscopy, Confocal / Q000379:methods*; D010575:Pesticides / Q000032:analysis*; D012680:Sensitivity and Specificity; D012828:Silicones / Q000737:chemistry*; D018030:Silver Compounds / Q000737:chemistry; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D004129:Dimethylpolysiloxanes; D010575:Pesticides; D012828:Silicones; D018030:Silver Compounds; D008743:Methyl Parathion; C013830:baysilon