Aptamers as molecular tools for bioanalytical methods.

Aptamers are single-stranded DNA or RNA ligands that can be selected from large libraries containing randomly created nucleic acids and used to target various molecules, ranging from proteins to small organic dyes. Because of the unique characteristics (eg, versatility, specificity and synthetic nature) of aptamers, mainly derived from their nucleic acid composition, these molecules represent ideal ligands for bioanalytical applications. In this review, the evolving use of aptamers in bioanalytical methods by exploiting their biochemical properties, for example, the use of aptamers in combination with nanoparticles in electrochemical and optical techniques, is discussed, with an emphasis on the most original, recently published aptamer-based studies.