Electrochemical (Bio)sensors for Toxins Control in the Marine Environment

The effects of climate change and human-caused pollution affect the oceans’ ecosystems through factors such as warming and acidification. These effects cause the formation of harmful algal blooms (HABs) that produce marine toxins (MTs) (e.g. Tetrodotoxin, Palytoxin, Ciguatoxin, Brevetoxin), which are a serious threat to human health and a vital concern for the fishery industry. HABs also expand and consequently occur with increasing frequency in previously unaffected areas. Traditional methods for toxin analysis, despite being reliable, are laborious and expensive, and require highly specialized equipment only available in centralized laboratories. Therefore, fast and portable analytical sensors, enabled to perform in situ analysis, have emerged to circumvent these problems. Biosensors, which show high selectivity because of the use of a recognition element, represent these attractive alternatives, resulting in exceptional miniaturized devices that meet the required analytical performances. This chapter focuses on electrochemical (bio)sensors for the detection of emerging MTs. First, the importance and sources of these MTs are summarized and then, the concept of electrochemical biosensors, their main components and detection techniques, are briefly explained. Finally, an overview of the reported (bio)sensors for these toxins is included, highlighting their main characteristics regarding construction, analytical features, and applications.