A review on designing biosensors for the detection of trace metals

摘要

Surface mining is one of the main activities that affects the environment, economy and society in its surrounding region. Therefore, it is important to investigate the results of this activity on the basis of sustainability assessment. One of fundamental issues in mining activities is the pollution caused by the presence of trace metals that can spread through the soil and infiltrate water, thereby directly affecting the environmental index of sustainability. There are many methods that can be used for the detection of trace metals in soil and water, such as inductively coupled plasma (ICP) and X-ray fluorescence (XRF) techniques, but most of these strategies suffer from certain drawbacks which prevent their on-site use for the detection of trace metals. Many efforts have been made to introduce portable sensors for controling trace metal concentrations in the environment. A conventional sensor for the specific detection of an analyte, comprises two main parts namely, the transducer and sensing elements. In this regard, incorporation of novel structures into sensors like nanostructures can lead to significant improvements in the efficiency of devices with respect to sensitivity, selectivity, multiplexed detection capability and portability. Besides, sensing elements such as small molecules, DNA, proteins and bacteria, have been integrated into sensor design inorder to selectively bind to trace metals as molecular recognition probes. This review presents recent advances in the design of sensor, type of transducer and sensing elements for the detection of trace metals. Regarding the type of transducer, optical, chemical, electrochemical and field-effect transistor sensors will be discussed. Furthermore, different types of specific sensing elements for binding to trace metals are also highlighted.