Aptamer: The Science of Synthetic DNA

Abstract

Aptamers are synthetic molecules (DNA/RNA) and have shown immense potential in the field of diagnostics and therapeutics. They are easy to produce and their manufacturing cost is very low, further they can be selected against toxic molecules which otherwise be not possible with antibodies. Synthetic aptamers have shown selectivity and sensitivity which is comparable to monoclonal antibodies. Tuerk and Gold used an iterative method also known as Systematic Evolution of Ligand by Exponential Enrichment (SELEX) for selection of an aptamer against bacteriophage T4 DNA polymerase. Since then many more aptamers are selected through SELEX that are specific to wide variety of molecules. Initial version of SELEX was time consuming and difficult to perform. To make process fast and more reliable advance version of SELEX has been developed. Till date only two aptamers have commercialized, Macugen (RNA aptamer) for treatment of macular degeneration and aptamer based bioassay for detection of Ochratoxins. The development in nanotechnology and immobilization techniques for aptamer tagging on different format of diagnostic techniques has made fast and sensitive detection method development. However despite of its advantages constrains such as nuclease sensitivity and less efficient working in vivo condition needs to be addressed so that aptamers can be used as an alternate to monoclonal antibody in near future.