title: Development of gold nanoparticles modified screen-printed carbon electrode for the analysis of thiram, disulfiram and their derivative in food using ultra-high performance liquid chromatography.
abstract: For the first time, gold nanoparticles (AuNPs) modified screen-printed carbon electrode (SPCE) was developed as working electrode in ultra-high performance liquid chromatography (UHPLC) coupled with electrochemical detection (UHPLC-ED) for simultaneous determination of thiram, disulfiram, and N,N-diethyl-N',N'-dimethylthiuram disulfide, their derivative compound. The separation was performed in reversed-phase mode using C18 column, mobile phase consisting of 55:45 (v/v) ratio of 0.05 M phosphate buffer solution (pH 5) and acetonitrile at a flow rate of 1.5 mL min(-1). For the detection part, the amperometric detection was chosen with a detection potential of 1.2 V vs. Ag/AgCl. Under the optimal conditions, the good linear relationship was obtained in the range of 0.07-15, 0.07-12, and 0.5-15 µg mL(-1) (correlation coefficient more than 0.9900) for thiram, N,N-diethyl-N',N'-dimethylthiuram disulfide, and disulfiram, respectively. The limits of detection (LODs) of thiram, N,N-diethyl-N',N'-dimethylthiuram disulfide, and disulfiram were 0.022, 0.023, and 0.165 µg mL(-1), respectively. Moreover, this method was successfully applied for the detection of these compounds in real samples (apple, grape and lettuce) with the recoveries ranging from 94.3% to 108.8%. To validate this developed method, a highly quantitative agreement was clearly observed compared to standard UHPLC-UV system. Therefore, the proposed electrode can be effectively used as an alternative electrode in UHPLC-ED for rapid, selective, highly sensitive, and simultaneous determination of thiram, disulfiram, and N,N-diethyl-N',N'-dimethylthiuram disulfide.
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok 10330, Thailand.
authors.forename: Kanokwan
authors.initials: K
authors.lastname: Charoenkitamorn
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok 10330, Thailand; National Center of Excellent of Petroleum, Petrochemicals and Advanced Materials, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand. Electronic address: corawon@chula.ac.th.
authors.forename: Orawon
authors.initials: O
authors.lastname: Chailapakul
authors.affiliation: Department of Chemistry, Faculty of Science, Srinakharinwirot University, Sukhumvit 23, Wattana, Bangkok 10110, Thailand. Electronic address: weenasi@hotmail.com.
authors.forename: Weena
authors.initials: W
authors.lastname: Siangproh
mesh_terms: D002244:Carbon / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004221:Disulfiram / Q000032:analysis*; D055664:Electrochemical Techniques; D004566:Electrodes; D005506:Food Contamination / Q000032:analysis; D005659:Fungicides, Industrial / Q000032:analysis*; D006046:Gold / Q000737:chemistry*; D006801:Humans; D018545:Lactuca / Q000737:chemistry; D057230:Limit of Detection; D027845:Malus / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D013859:Thiocarbamates / Q000032:analysis*; D013893:Thiram / Q000032:analysis*; D027843:Vitis / Q000737:chemistry
chemical_list: D005659:Fungicides, Industrial; D013859:Thiocarbamates; D013893:Thiram; C479164:dimethylthiuram disulfide; D002244:Carbon; D006046:Gold; D004221:Disulfiram
keywords: Dithiocarbamates; Fungicides; Gold nanoparticles; Screen-printed carbon electrode; Simultaneous determination; Ultra-high performance liquid chromatography