title: A microscale solid-phase extraction poly(dimethylsiloxane) chip for enrichment and fluorescent detection of metal ions.
abstract: A rapid and simple enrichment system was developed on microfluidic chip which was integrated with on-line complexing and fluorescence detection. Microparticles of ion-exchange resin were trapped into the microchannel by a fabricated weir-structure in the end of the microchannel to construct a micro-solid-phase extraction (μ-SPE) device. Some commonly existing metal ions in environment were served as models to evaluate the performance of the proposed microdevice, in combination with on-line derivatization with 8-hydroxyquinolin-5-sulfonic acid (HQS) and fluorescence detection. The concentration and pH value of HQS solution were optimized for metal-HQS fluorescent derivatization. The parameters, which affected the efficiency of the developed method, including composition and concentration of eluent, pH value and the flow rate of HQS solution and elution, were also investigated. Under the optimal conditions, Ca(2+), Mg(2+), Zn(2+) and Pb(2+) were successfully determined by the μ-SPE device on-chip. The experimental enrichment factors for Ca(2+), Mg(2+), Zn(2+) and Pb(2+) were up to 520, 565, 578 and 487 folds, respectively.
authors.affiliation: Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Tsinghua University, Beijing 100084, China; Department of Applied Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, Minamiosawa, Hachioji, Tokyo 192-0397, Japan.
authors.forename: Shuhua
authors.initials: S
authors.lastname: Xue
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Hai-Fang
authors.initials: HF
authors.lastname: Li
authors.forename: Katsumi
authors.initials: K
authors.lastname: Uchiyama
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Lin
mesh_terms: D002118:Calcium / Q000302:isolation & purification*; D002413:Cations, Divalent; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007475:Ion Exchange Resins; D007854:Lead / Q000302:isolation & purification*; D008274:Magnesium / Q000302:isolation & purification*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D015125:Oxyquinoline / Q000031:analogs & derivatives / Q000737:chemistry; D052617:Solid Phase Microextraction; D013050:Spectrometry, Fluorescence; D014867:Water / Q000737:chemistry*; D015032:Zinc / Q000302:isolation & purification*
chemical_list: D002413:Cations, Divalent; D004129:Dimethylpolysiloxanes; D007475:Ion Exchange Resins; D014867:Water; D007854:Lead; D015125:Oxyquinoline; C013830:baysilon; C013053:8-hydroxyquinoline-5-sulfonic acid; D008274:Magnesium; D015032:Zinc; D002118:Calcium
keywords: 8-Hydroxyquinolin-5-sulfonic acid; Enrichment; Fluorescence detection; Microscale solid-phase extraction; Poly(dimethylsiloxane)