Recent advances on the electrochemical transduction techniques for the biosensing of pharmaceuticals in aquatic environments

Abstract

The presence of pharmaceuticals in the aquatic environment (e.g. rivers, lakes, sewage, estuarine and marine water) merits special attention due to its significant impact as potentially harmful pollutants.1 The worldwide concern on this issue is due to the concentration in which these substances have been found in water bodies (from nanogram per liter to microgram per liter),2 overcoming the acceptable levels to ensure the safety of aquatic organisms.3 The source of these pollutants comprises the human and animal healthcare, which tends to continuously be rising as a function of the advances in the medical treatments, the larger amount of medicines available to combat well known and recently discovered diseases, affordability, the growing number of people in the world and their respective larger life expectancy.4 Pharmaceuticals and personal care products are considered emerging contaminants, which means that just in the past two decades they have been studied and deeply investigated. Moreover, the fragility of the current analytical tools to detect these molecules at low concentrations hinders the regulation and monitoring of drinking water supplies.3 Puckowski et al.,2 complement that few information concerning the presence of pharmaceuticals in the biota are available possibly because of the complexity of the experimental setup to analyze the contaminated samples and due to the possibility of bioaccumulation in the surrounding areas. Therefore, the development of new technologies and techniques that are more efficient in the detection and analyses of pharmaceuticals is required. Recently, the biosensor technology has been an important method-of-choice for this purpose due to its particularly interesting characteristics, such as its portability, capability of on-site detection, the low time of response and the advantageous lower price in comparison to traditional laboratory techniques.5 Within this scenario, this mini review presents the types of biosensors currently available, the newest researches performed in the area, the challenges still faced in the monitoring of pharmaceuticals in the aquatic ecosystems, promising futures perspectives as well as the open fields for new researches in this field.