Photoacoustics and Fluorescence based Nanoprobes towards Functional and Structural Imaging in vivo.

Nanoprobes;Chemical Sensing;Structural Imaging;Fluorescence;Photoacoustics;Biomedical Engineering;Engineering;Biophysics

Ray, AniruddhaOgilvie, Jennifer P. ;

University of Michigan

关键词: Nanoprobes;    Chemical Sensing;    Structural Imaging;    Fluorescence;    Photoacoustics;    Biomedical Engineering;    Engineering;    Biophysics;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/97847/rayani_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Imaging of chemical analytes and structural properties related to physiological activities within biological systems is of great bio-medical interest; it can contribute to the fundamental understanding of biological systems and can be applied to the diagnosis and prognosis of diseases, especially tumors. The work presented in this thesis focuses on the development and application of polymeric nanoprobe aided optical imaging of chemical analytes (Oxygen, pH) and structural properties in live cells and animal models. To this end, specific nanoprobes, based on the polyacrylamide nanoplatform, bearing both appropriate targeting functionalities, and high concentrations of sensing and contrast agents, have been developed. The nanoprobes presented here are biodegradable, biocompatible and non-toxic, rendering them safe for in vivo use. Furthermore the nanoprobes are designed to have variable optical properties that are dependent on the local concentration of the specific analyte of interest. Optical imaging techniques that are particularly suited for deep tissue applications, such as two-photon fluorescence and photoacoustics, were applied for non-invasive real-time imaging and sensing in cancer cells, tumor spheroids and animal models. Our results demonstrate that this technique enables high sensitive detection of chemical analytes with a sensitivity of <5 Torr for oxygen and <0.1 pH units in vivo, which is better than the currently available in vivo functional imaging techniques. This non-invasive and non-ionizing, yet low cost, method will enable morphological and functional evaluation across any tissue, with both high spatial and temporal resolution but without eliciting short- or long-term tissue damage. Currently no gold standard exists for such functional imaging. The approach presented here can be used for early detection and diagnosis of tumors, as well as for monitoring the progression of disease and therapy. This technique will also enable observing phenomena at the cellular level in vivo that would lead to a better understanding of the pathophysiology of diseases as well as the disease onset, progression, and response to therapy.