Applications of aptasensors in clinical diagnostics

Abstract

Aptamers are artificial oligonucleotides (DNA or RNA) selected in vitro that bind a broad range of targets with high affinity and specificity; a sensitive yet simple method to utilize aptamers as recognition elements for the development of biosensors (aptasensors) is to transduce the signal electrochemically. So far, aptasensors have been applied to clinical diagnostics and several technologies are in development. Aptasensors will extend the limits of current clinical diagnostics. Although the potential diagnostic applications are unlimited, the most current applications are foreseen in the areas of biomarker detection, cancer clinical testing, detection of infectious microorganisms and viruses. This review attempts to list examples of the research progresses of aptamers in biosensor platforms that have been published in recent years; in particular, we display cases of aptasensors that are already incorporated in clinical diagnostics or have potential applications in clinical diagnostics.

Keywords: aptamer; aptasensors; biosensor; clinical diagnostics.

Scheme 1.

Schematic diagrams of preparation of the sandwich-type electrochemical aptasensor and TEM images of the hollow CoPt alloy nanoparticles decorated graphene. Reproduced with permission form Reference [25] (Abbreviations: HT, hexanethiol; GCE, glassy carbon electrode; CS-HCoPt, the chitosan-hollow CoPt alloy nanoparticle).

Scheme 2.

Schematic representation of the reusable aptamer/graphene-based aptasensor. The sensor is constructed based on graphene-modified electrode and the first clinical trials II used aptamer, AS1411. AS1411 and its complementary DNA are used as a nanoscale anchorage substrate to capture/release cells. Reproduced with permission form Reference [39]. (Abbreviations: CCG, chemical converted grapheme; EDC, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide; NHS, N-hydroxysuccinimide).