Biosensors Made of Synthetic Functional Nucleic Acids Toward Better Human Health.

Abstract

The invention of the in vitro selection technique, or SELEX (Systematic Evolution of Ligands by EXponential enrichment), in the early 1990s, identified single-stranded (ss) nucleic acid molecules with catalytic or binding properties from random-sequence nucleic acid libraries.1–3 This technique has given rise to intensive examinations of synthetic functional nucleic acids (aptamers and nucleic acid enzymes) for wide-ranging applications including biosensors, diagnostics and therapeutics.4–9After nearly three decades of research by many groups around the world, many functional nucleic acids have been isolated and characterized. A few well-known examples are provided in Figure 1, including two RNA-cleaving DNAzymes (8-17 and 10-23),10 a peroxidase-mimicking DNAzyme (PS2.M),11 two DNA aptamers that bind human α-thrombin (TBA15 and TBA29),12,13 a DNA aptamer that binds ATP,14 and a modified nucleic acid aptamer that binds human VEGF-165 (Pegaptanib).15 Thousands of papers have been published describing the us...