Heavy metals (HMs) are ubiquitous in our environment, representing a real danger both to ecosystems and human health. Pollution caused by heavy metals often arises from industrial activities; severe environmental degradation and threats to human health may result. Therefore, it is necessary to establish sensitive and small-size methods for heavy metal detection in order to determine their concentrations throughout the environment as well as any resulting health issues.
In recent years, the preferred approach for on-site heavy metal pollution screening has been electrochemical sensing methods. Electrochemical sensors are increasingly common in applications, with their excellent sensitivity and precision; long-term stability; low cost of production by means similar to those used for semiconductor integrated circuits (ICs), which results in a smaller apparatus capable of handling samples more easily than do other types. Therefore a number of smaller electrochemical devices using various nanomaterials have been designed and used in all kinds of fields.
A group of scientists from Pusan National University (PNU) in South Korea have conducted a comprehensive review on the latest developments concerning electrochemical sensors designed to detect heavy metals. Prof. Seung-Cheol Chang, the head of this research says that portable electrochemical sensors must be both economical and easy to use; for field study in particular the old methods frequently do not work since traditional analysis is too slow.
Electrochemical sensors form an important subclass of all electro-sensors. Nanomaterial-based ones have remarkable sensitivity and selectivity. These sensors make possible very accurate detection of ultra-trace amounts of heavy metals in a vast array of environmental settings. Even with these advances, the study team does admit to some limits.
On-site research is bedeviled by poor selectivity, inadequate detail and the interference of non native species. In addition, as dissolved oxygen species corrode these sensors ‘ability to sense things over time. The researchers favor the development of wearable, disposable and flexible electrochemical sensors as well as lab-on-a chip methods which can be mass produced to solve these problems.
Moreover, the team stresses that only with advanced electrochemical detection techniques can we get high precision results–and this is especially true for human biofluid samples like blood, urine or saliva. These biofluids create special difficulties and opportunities for sensing heavy metals. Detection in these matrices can have particularly important implications to people’s health.
Talking about the direction of research in electrochemical sensors for heavy metals, Professor Chang points out that it is very difficult to turn cutting-edge concepts from academic institutions or government organisations into commercial products. Nonetheless, he expresses optimism that future research in electronics and materials technology can resolve current problems with on-site heavy metal detection.
In sum, this thorough review offers some insight into the recent advances in miniaturised electrochemical sensors for heavy metal detection. As such, this study takes a critical look at these limitations and stresses the importance of taking new approaches. The findings are also very important for current work as well as that to be done in future years so that we can create an even safer healthier environment.
