Trace Detection of Mercury(II) Using Gold Ultra-Microelectrode Arrays

✍ Scribed by Olga Ordeig; Craig E. Banks; Javier del Campo; Francesc Xavier Muñoz; Richard G. Compton

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 411 KB
• Volume: 18
• Category: Article
• ISSN: 1040-0397
• DOI: 10.1002/elan.200503437

✦ Synopsis

The electroanalytical detection of trace mercury(II) at gold ultra-microelectrode arrays is reported. The arrays consist of 256 gold microelectrodes of 5 mm in diameter in cubic arrangements which are separated from their nearest neighbor by 100 mm. The array was utilized in nitric acid using linear sweep voltammetry where a linear response from mercury additions over the range 10 mg L À1 À 200 mg L À1 (10 À8 À 10 À6 M) was observed with a sensitivity and detection limit of 0.11 nC/mg L À1 and 3.2 mg L À1 (16 nM) respectively from using a deposition time of 30 s at À 0.2 V (vs. SCE). This methodology was explored in 0.1 and 1 M chloride media over the mercury range 10 mg L À1 À 200 mg L À1 (5 Â 10 À8 À 10 À6 M) where similar sensitivities of 0.087 nC/mg L À1 and 0.078 nC/mg L À1 were observed with an identical detection limit. The protocol is demonstrated to be useful for the determination of mercury for analysis of environmental water samples.