Optical Coherence Microscopy (OCM) towards tomography
Final Report Abstract
During the second phase of this research project, we have prepared novel biopolymers with various functionalities attached to the backbone such as polyethyleneglycol chains to enhance solubility and stability, positively charged amino groups to facilitate interactions with cellular membranes, TAT peptides to initiate cellular uptake and endosomal release as well as triphenylphosphonium groups for mitochondria targeting. After coating, the gold nanoparticles were uptaken into cells and released into the cytosol. We could prove that they trafficked into mitochondria and we have assessed dynamic processes of mitochondria with spatial and temporal resolution microscopy over extended time periods at sub- cellular scales. Imaging mitochondrial dynamics was accomplished by photo-thermal optical lock-in OCM (poli-OCM). within living cell in all three dimensions. The preparation of gold nanoparticles with customized surface functions providing cellular uptake, endosomal release and trafficking into mitochondria was essential for reaching the desired sensitivity and resolution. In addition, we have prepared an entirely novel biopolymer that also combined phototoxic ruthenium complexes. Gold nanoparticles coated with this biopolymer could induce the formation reactive oxygen species in mitochondria by irradiation. These studies would be of great interest to elucidate the impact of oxidative stress on mitochondria dynamics. Overall, this interdisciplinary project resides on the broad variety of technologies, materials, tools and skills shared between both research teams. 15 publications have been published over the entire funding period (over four years) by the German team and some of these were coauthored by both teams and published in highly cited journals such as Nano Letters, Scientific Reports and Biomaterials Science.
Publications
- Combined Optical Coherence and Fluorescence Microscopy to assess dynamics and specificity of pancreatic beta-cell tracers, Scientific Reports, 5, 10385, 2015
C. Berclaz et al.
(See online at https://doi.org/10.1038/srep10385) - Longitudinal three-dimensional visualisation of autoimmune diabetes by functional optical coherence imaging, Diabetologia, 59 (3), 550-559, 2016
C. Berclaz
(See online at https://doi.org/10.1007/s00125-015-3819-x)
