Screen-printed Electrochemical Sensors and Biosensors for Monitoring Metal Pollutants

The present review (with 231 references) focuses on developments made in the area of screen-printed biosensors and sensors for the determination of metal ions in industrial, environmental and biomedical applications. The year 2012 represents the twentieth anniversary of the first reported application of screen-printed electrodes for the determination of metal ions. Focus is placed on fabrication techniques, operating details and performance characteristics for the selected applications. The greater proportion of articles have utilised the technique of stripping voltammetry, gaining detection limits in the low ng/mL (ppb) region. An increasing percentage of these have explored bismuth as an alternative to mercury for the modification of the carbon electrode surface. However, a steady number of applications have shown the possibility of utilising the unmodified screen-printed carbon, gold or silver electrode surface. More recently the alternative approach of electrochemical biosensors has become a growing area. The majority of these have exploited the inhabitation metal ions exhibit on the enzyme activity of urease, acetylcholinesterase and glucose oxidase gaining detection limits in the sub μg/mL region, however recent applications utilising thiol-functionalised oligonucleotides have been shown the possibility of gaining detection limits as low as 120 ng/L for Hg.