title: Design of fluorescent self-assembled multilayers and interfacial sensing for organophosphorus pesticides.
abstract: This paper details the fabrication of indole (ID) self-assembled multilayers (SAMs) and fluorescence interfacial sensing for organophosphorus (OP) pesticides. Quartz/APES/AuNP/L-Cys/ID film was constructed on L-cysteine modified Quartz/APES/AuNP surface via electrostatic attraction between ID and L-cysteine. Cyclic voltammetry indicates that ID is immobilized successfully on the gold surface. Fluorescence of the Quartz/APES/AuNP/L-Cys/ID film shows sensitive response toward OPs. The fluorescent sensing conditions of the SAMs are optimized that allow linear fluorescence response for methylparathion and monocrotophos over 5.97 x 10(-7) to 3.51 x 10(-6)gL(-1) and 3.98 x 10(-6) to 3.47 x 10(-5)gL(-1), with detection limit of 6.1 x 10(-8)gL(-1) and 3.28 x 10(-6)gL(-1), respectively. Compared to bulk phase detection, interfacial fluorescence sensing based on the SAMs technology shows higher sensitivity by at least 2 order of magnitude.
authors.affiliation: College of Material Science and Engineering, The Key Laboratory of Functional Materials for Fujian Higher Education, Huaqiao University, Quanzhou 362021, China. liumy@hqu.edu.cn
authors.forename: Xiangying
authors.initials: X
authors.lastname: Sun
authors.forename: Kaihao
authors.initials: K
authors.lastname: Xia
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000379:methods*; D003545:Cysteine / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods; D005456:Fluorescent Dyes / Q000494:pharmacology; D006046:Gold / Q000737:chemistry; D007211:Indoles / Q000032:analysis / Q000737:chemistry; D053768:Metal Nanoparticles; D008743:Methyl Parathion / Q000032:analysis; D008999:Monocrotophos / Q000032:analysis; D010755:Organophosphates / Q000032:analysis* / Q000737:chemistry; D010575:Pesticides / Q000032:analysis* / Q000737:chemistry; D011791:Quartz; D055672:Static Electricity
chemical_list: D005456:Fluorescent Dyes; D007211:Indoles; D010755:Organophosphates; D010575:Pesticides; D011791:Quartz; D008743:Methyl Parathion; D008999:Monocrotophos; D006046:Gold; D003545:Cysteine