Engineering Aptamer and SIRNA Based Drug Delivery Systems Using Polyelectrolyte Multilayer Films
Srivatsan Kidambi1, Ilsoon Lee, and Christina Chan2. (1) Department of Chemical Engineering and Materials Science, Michigan State University, 2527, Engineering Building, East Lansing, MI 48824, (2) Chemical Engineering and Material Science, Michigan State University, 2527 Engineering Building, East Lansing, MI 48824
This work describes the successful immobilization and patterning of aptamers and siRNAs on Polyelectrolyte Multilayer (PEM) films using electrostatic interaction and covalent crosslinking of nucleic acids on top of the thin films. Patterns of nucleic acids and of thrombin aptamers were formed on PEM surfaces by microcontact printing (μCP) the nucleic acids onto the PEM surfaces. This technique may be used to fabricate aptamer arrays to detect and quantitate proteins. We investigated the presence and stability of the aptamers on the PEM films with ellipsometry, FTIR, optical microscope and QCM. Our preliminary studies indicate that the FITC labeled RNAs were taken up by fibroblasts and primary hepatocytes providing confidence that this effect may be extended to aptamers and siRNA molecules attached on top of the PEM surface. Further studies focus on targeting a specific antigen with the aptamer and siRNA molecules attached on the PEM surfaces. A comparative study with several cell types, including cell lines and primary cells, were performed to determine the delivery efficiency of the DNA and RNA molecules to these different cell types. These results set the groundwork for assembling aptamers and siRNAs to create targeted delivery systems.