title: A novel miniaturized zinc oxide/hydroxylated multiwalled carbon nanotubes as a stir-brush microextractor device for carbamate pesticides analysis.
abstract: A novel miniaturized "stir-brush microextractor" was prepared using a zinc oxide/hydroxylated multiwalled carbon nanotubes (ZnO/MWCNTs-OH) coated stainless steel brush connected to a small dc motor. The synthesized zinc oxide on each strand of stainless steel had a flower-like nanostructure when observed by a scanning electron microscope (SEM). This structure produced a large surface area before it was coated with the hydroxylated multiwalled carbon nanotubes sorbent. Under optimal conditions, the developed device provided a good linearity for the extraction of carbofuran and carbaryl, in the range of 25-500 ng mL(-1) and 50-500 ng mL(-1), respectively, with low limits of detection of 17.5 ± 2.0 ng mL(-1) and 13.0 ± 1.8 ng mL(-1). It also provided a good stir-brush-to-stir-brush reproducibility (% relative standard deviation < 5.6%, n = 6). The device was applied for the extraction and preconcentration of carbamate pesticides in fruit and vegetable samples prior to analysis with a gas chromatograph coupled with a flame ionization detector (GC-FID). Carbofuran was found at 9.24 ± 0.93 ng g(-1) and carbaryl was detected at 7.05 ± 0.61 ng g(-1) with good recoveries in the range of 73.7 ± 10.0% to 108.4 ± 2.6% for carbofuran and 75.7 ± 10.0% to 111.7 ± 5.7% for carbaryl.
authors.affiliation: Trace Analysis and Biosensor Research Center, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand; Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand.
authors.forename: Fonthip
authors.initials: F
authors.lastname: Makkliang
authors.affiliation: Trace Analysis and Biosensor Research Center, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand; Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand.
authors.forename: Proespichaya
authors.initials: P
authors.lastname: Kanatharana
authors.affiliation: Trace Analysis and Biosensor Research Center, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand; Department of Physics, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand.
authors.forename: Panote
authors.initials: P
authors.lastname: Thavarungkul
authors.affiliation: Trace Analysis and Biosensor Research Center, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand; Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand. Electronic address: chongdee.t@psu.ac.th.
authors.forename: Chongdee
authors.initials: C
authors.lastname: Thammakhet
mesh_terms: D002219:Carbamates / Q000032:analysis*; D002849:Chromatography, Gas; D006900:Hydroxylation; D008855:Microscopy, Electron, Scanning; D008904:Miniaturization; D037742:Nanotubes, Carbon; D010575:Pesticides / Q000032:analysis*; D015203:Reproducibility of Results; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D002219:Carbamates; D037742:Nanotubes, Carbon; D010575:Pesticides; D015034:Zinc Oxide
keywords: Carbamate pesticides; Miniaturized solid phase extraction; Multiwalled carbon nanotubes; Trace analysis; Zinc oxide