Electrochemical methods for the detection of heavy metal ions: From sensors to biosensors

Naturally occurring heavy metals (HMs) present a serious risk to human health and the environment because of their toxicity, persistence, and tendency to bioaccumulate. Their presence in air, water, soil, and food can lead to a multitude of adverse effects, from acute poisoning to chronic health problems. The rapid expansion of industrialization and technology has increased HMs contamination from industrial emissions, mining, agriculture, urbanization, and e-waste, posing serious risks to ecosystems and public health. To tackle this increasing challenge, it is essential to develop highly robust, sensitive, and selective electrochemical detection methods for the rapid identification of heavy metal ions (HMIs) contaminants. This review investigates a variety of electrochemical sensors and biosensors utilizing voltammetric techniques for HMIs detection. It covers voltammetric methods such as cyclic voltammetry (CV), square wave voltammetry (SWV), differential-pulse voltammetry (DPV), normal pulse voltammetry (NPV), staircase voltammetry (SV), linear sweep voltammetry (LSV), hydrodynamic voltammetry (HV), anodic stripping voltammetry (ASV), cathodic stripping voltammetry (CSV), and adsorptive stripping voltammetry (AdSV). The review also emphasizes recent advancements in the electrochemical detection of HMIs through various sensor and biosensor platforms, including different nanomaterials and DNA aptamers. These innovations have potential applications in environmental monitoring, food and water safety, industrial waste management, and public health protection, making them vital tools for safeguarding human health and the environment from HMIs contamination.