Electrochemical Sensors

Abstract

This review covers publications related to electrochemical sensors that appeared in print during the years 2006 and 2007. The focus of the review is on the development of electrochemical sensing principles including potentiometric and chronopotentiometric sensors, reference electrodes, voltammetric sensors, and electrochemical biosensors.References were collected by searching electrochemical sensor-related work using ACS SciFinder and ISI Science Citation Index. In addition, the tables of contents of several analytical journals were reviewed manually to identify relevant articles. Only original and review articles written in English were considered. Patents, book chapters or book series, and conference proceedings or abstracts were not considered for this review. The number of references was limited to 200 and as a result only a fraction of relevant work is covered. Specifically, the review was written to focus on fundamental aspects of electrochemical sensor research emphasizing new chemical concepts and not simply the application of electrochemical sensors. On the basis of these guidelines, several hybrid systems whereby electrochemical detection schemes were combined with a separation technique such as microdialysis, electrophoresis, chromatography, and lab-on-a-chip were not included in this review.We ask that our readers note that our review is not a comprehensive coverage of the above topics, but rather a snapshot of research conducted over the past two years. Obviously, electrochemical sensor research is still expanding and of interest to a number of disciplines beyond traditional chemistry. As such, it was not possible to cover all manuscripts published. We apologize to the authors of manuscripts that were not included in this review. POTENTIOMETRIC SENSORS ReviewsBakker and Pretsch published a broad review on modern potentiometry describing techniques for improving sensor performance, miniaturizing sensor platforms, and expanding the application of potentiometric sensors for environmental trace analysis and biosensing (98 citations). 1 Likewise, Pretsch provided a general overview on ion-selective electrodes (ISEs) focusing on improving detection limits and understanding non-classical (i.e., non-equilibrium) potentiometry for monitoring clinical relevant polyions such as heparin and protamine (81 citations). 2 De Marco et al. reviewed ISE methodologies for the analysis of trace metals and anions (e.g., F − , CN − , NO 3 − , NO 2 − , and Cl − ) in environmental samples. 3