Aptameric Microfluidic Systems for Affinity Manipulation and Biosensing
Aptamers are oligonucleotides (DNA or RNA) that specifically bind to biochemical analyte targets via affinity interactions. Aptamers are generated by systematic evolution of ligands by exponential enrichment (SELEX), an in vitro, synthetic process in which large populations of oligonucleotides are successively selected and amplified to isolate target-binding strands. Due to the synthetic nature, aptamers can be developed for an extremely broad spectrum of analytes with high affinity (e.g., small molecules, proteins, cells, viruses, and bacteria), can possess well controlled target selectivity, and may have the ability to bind targets with predefined characteristics. As such, aptamers offer a highly attractive alternative to more commonly used affinity receptors such as antibodies and enzymes, which are typically generated from laboratory animals. Our research has involved creating microfluidic devices and systems that exploit aptamers to enable innovative applications in affinity purification and biosensing.