DNA-functionalized nanoparticles for drug delivery

• Main Author: Ong, Onn Shaun.
• Other Authors: School of Materials Science and Engineering
• Format: Final Year Project
• Language: English
• Published: 2012
• Subjects: DRNTU::Engineering::Materials::Biomaterials
• Online Access: http://hdl.handle.net/10356/48394
• Institution: Nanyang Technological University

The use of nanoparticles for drug delivery is an emerging nanotechnology that has generated much interest in overcoming challenges of current drug delivery systems (DDS) and replacing them. Mesoporous silica nanoparticles (MSNs) can be modified to provide for dual-stimulus responsive drug release. The capping mechanism involves short single stranded DNA (ssDNA) and long complementary single stranded DNA (cDNA). ssDNA was immobilized onto the MSN surface. For every two ssDNA, a single cDNA is hybridized with them to form double stranded DNA (dsDNA). The hybridization of these two kinds of DNA shows the capacity to cap the mesopores. In this project, the DNA-functionalized MSNs bridged with disulfide bonds (MSNs-SS-dsDNA) were synthesized and characterized. One mode for controlled release of MSNs-SS-dsDNA loaded with model drug fluorescein isothiocyanate (FITC) was carried out by cleaving the pre-installed disulfide linkage between the nanoparticle surface and dsDNA. The other mode for controlled release was achieved by direct heating to denature the hybridized dsDNA on the surface. The potential application of the on-demand drug delivery mechanism making use of dsDNA properties was also investigated, showing encouraging preliminary results. Therefore, the use of nucleic acids as capping agents has proved to be a promising prospect in the development of on-demand DDS.