Engineering of Nanovectors for Multimodal Medical Imaging

Abstract

newlineIn this thesis, multiple contrast agents for application in multimodal imaging was fabricated based on various nanovectors. The core focus of the works presented were based on the limitations posed by the traditional contrast agents employed in various diagnostic imaging modalities. Additionally, cross-referenced diagnoses among imaging modalities with the availability of a single imaging agent for multimodal applications was of essence in the presented studies. Nanovectors based on manganese ferrite magnetic nanoparticles were chosen as the core nanomaterial with the aim of optimizing the manganese and iron ratios for dual T1-T2 magnetic resonance imaging applications while nano-silver coating was used to generate contrast differences in CT imaging. Surface modifications with dendrimers and serum proteins were made for their unique features in order to make the core magnetic nanoparticles biocompatible. A unique approach in the synthesis of magnetic nanoclusters with protein stabilization was developed to generate inherent fluorescence properties enabling the application of these nanoclusters in MRI as well as in optical imaging modalities. The abilities of the fabricated nanovectors to act as a multifunctional agent was also analyzed through their drug carrying capabilities and antitumoral activities leading to their applications in theranostics. Targeted delivery of the engineered nanovectors was enumerated using folic acid that enables receptor mediated endocytosis. The properties of these nanovectors were characterized at each stage using various techniques including XRD, FTIR, UV-visible spectrophotometer, particle size analysis, SEM and TEM. Phantom and in vivo imaging studies using MRI, CT and optical imaging were engaged to confirm the contrasting abilities of the engineered nanovectors for their application in multimodal diagnostic imaging.