Degree Type
Dissertation
Date of Award
2004
Degree Name
Doctor of Philosophy
Department
Chemistry
First Advisor
Victor Shang-Yi Lin
Abstract
The central theme of this dissertation is represented by the versatility of mesoporous silica nanomaterials in various applications such as catalysis and bio-applications, with main focus on biological applications of Mesoporous Silica Nanospheres (MSN). The metamorphosis that we impose to these materials from catalysis to sensing and to drug and gene delivery is detailed in this dissertation. First, we developed a synthetic method that can fine tune the amount of chemically accessible organic functional groups on the pores surface of MSN by exploiting electrostatic and size matching between the cationic alkylammonium head group of the CTAB surfactant and various anionic organoalkoxysilane precursors at the micelle-water interface in a base-catalyzed condensation reaction of silicate.;Aiming nature imitation, we demonstrated the catalytic abilities of the MSNs. We utilized an ethylenediamine functional group for chelating Cu 2+ as a catalytic functional group anchored inside the mesopores. Thus, a polyalkynylene-based conducting polymer (molecular wire) was synthesized within the Cu-functionalized MSNs silica catalyst.;For sensing applications, we have synthesized a poly(lactic acid) coated mesoporous silica nanosphere (PLA-MSN) material that serves as a fluorescence sensor system for detection of amino-containing neurotransmitters in neutral aqueous buffer. We exploited the mesoporosity of MSNs for encapsulating pharmaceutical drugs. We examined bio-friendly capping molecules such as polyamidoamine dendrimers of generations G2 to G4, to prevent the drug leaching. Next, the drug delivery system employed MSNs loaded with Doxorubicin, an anticancer drug. The results demonstrated that these nano-Trojan horses have ability to deliver Doxorubicin to cancer cells and induce their death.;Finally, to demonstrate the potential of MSN as an universal cellular transmembrane nanovehicle, we anchored positively charged dendrimers on the surface of MSN and utilize them to complex cationic DNA. The p-EGFP-C1 gene-coated MSN nanocomposite was able to transfect cancer cell lines, such as human HeLa and CHO cancer cell lines. The gene carrier ability of MSNs was further proved by transfecting primary cells and cotransfecting of two different genes in cancer cell lines.;In sum, MSN are versatile partners in several types of applications, as demonstrated in the 164 pages of my dissertation.
DOI
https://doi.org/10.31274/rtd-180813-15356
Publisher
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/
Copyright Owner
Daniela Rodica Radu
Copyright Date
2004
Language
en
Proquest ID
AAI3190724
File Format
application/pdf
File Size
164 pages
Recommended Citation
Radu, Daniela Rodica, "Mesoporous silica nanomaterials for applications in catalysis, sensing, drug delivery and gene transfection " (2004). Retrospective Theses and Dissertations. 1704.
https://lib.dr.iastate.edu/rtd/1704