Miniaturised stripping-based carbon modified sensor for in field analysis of heavy metals

A new miniaturised electrochemical carbon modified sensor for on-site stripping analysis of trace heavy metals is described. The graphite working electrode is modified with a cellulose-derivative mercury coating. A detailed description of the construction of the system as well as the systematic laboratory test carried out to optimise its performance is reported. Coupling this sensor with square wave (SW) anodic stripping analysis, detection limits of 0.3, 1 and 0.5 μg l −1 were found for lead(II), cadmium(II) and copper(II), respectively. Deoxygenation of sample solution is not required. The entire analysis time is shorter than 4 min. Examples of on-site environmental applications are given. In particular, on-site analysis of heavy metals was performed at a contaminated site. For this purpose, the sensor was coupled with a portable commercial electroanalytical instrumentation.