Aptamer Utility in Sensor Platformsfor the Detection of Toxins and Heavy Metals

Nucleic acid research has expanded in recent years through the development of an in vitro methodology for the derivation of functional nucleic acids, capable of binding to specific targets with high specificity and sensitivity. These activities are similar to those of antibodies, yet the single-stranded oligonucleotide, called aptamer, can be readily created on a large-scale using solid-phase oligonucleotide synthesis. This relative ease of synthesis has made aptamers a highly versatile tool for the detection of important targets for applications in imaging, diagnostics and therapeutics. Aptamers are able to show high fidelity to specific targets due to their selective affinities. They undergo structural alteration and topological changes when they bind to specific targets and most sensors using aptamers today leverage on this characteristic to record a detectable signal. The use of aptamers in modern applications is vast and cannot possibly be covered in a single review. This review explicitly focuses on DNA aptamers used for detecting toxins and heavy metals, and outlines their utility in contemporary sensor designs, and their future prospects as analytical tools.