This paper describes the fabrication, characterization and application of an environment-friendly tin film/gold nanoparticles (Sn/AuNPs) modified gold microelectrode for square wave stripping voltammetric (SWSV) determination of copper, lead and zinc. The microelectrode chips were fabricated by Micro Electro-Mechanical System (MEMS) technique. The sensitivity of the modified microelectrode was largely improved due to the large surface area of AuNPs and the formation of alloys between target metals and Sn. The influence of hydrogen overflow was reduced and the current response was enhanced because AuNPs made the stripping potential shift positively and Sn extended the stripping potential range. Combining AuNPs with Sn, the obtained microelectrode exhibited satisfied linearity ranges from 5 to 500 μg L-1 for copper and lead, from 10 to 500 μg L-1 for zinc, with a limit of detection of 2 μg L-1 for copper, 3 μg L-1 for lead and 5 μg L-1 for zinc. The Sn/AuNPs/gold microelectrode was successfully applied for simultaneous detection of copper, lead and zinc in tap water sample.
