Preparation of Functional Aptamer Films Using Layer-by-Layer Self-Assembly

Department of Chemistry, Carleton University, Ottawa-Carleton Chemistry Institute, 1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6.
Biomacromolecules (Impact Factor: 5.75). 05/2009; 10(5):1149-54. DOI: 10.1021/bm8014126
Source: PubMed


Advances in many aptamer-based applications will require a better understanding of how an aptamer's molecular recognition ability is affected by its incorporation into a suitable matrix. In this study, we investigated whether a model aptamer system, the sulforhodamine B aptamer, would retain its binding ability while embedded in a multilayer polyelectrolyte film. Thin films consisting of poly(diallyldimethylammonium chloride) as the polycation and both poly(sodium 4-styrene-sulfonate) and the aptamer as the polyanions were deposited by the layer-by-layer approach and were compared to films prepared using calf thymus DNA or a random single-stranded oligonucleotide. Data from UV-vis spectroscopy, quartz crystal microbalance studies, confocal microscopy, and time of flight secondary ion mass spectrometry confirm that the aptamer's recognition of its target is retained, with no loss of specificity and only a modest reduction of binding affinity, while it is incorporated within the thin film. These findings open up a raft of new opportunities for the development and application of aptamer-based functional thin films.

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Available from: Maria C Derosa, Oct 14, 2015
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    • "We concentrate on ultrathin polymer films on a dielectric substrate. We choose to work with polyelectrolyte films because their self-assembly as bilayers on surfaces is well understood and provides a way of producing uniform films of known thickness in a simple and reproducible manner [15]. The thickness is determined by the number of bilayers and can be controlled incrementally on a nanometer scale [16]. "
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