Doppler Spectroscopy of Intracellular Dynamics Inside Intact 3D Tissue

Intracellular dynamics are dominated by active transport driven by energetic processes far from equilibrium. Cytoskeletal restructuring, membrane motions and molecular motors use GTP and ATP to drive directed transport that is quasi-one-dimensional and produces lifetime-broadened Doppler light scattering. A new functional imaging approach called biodynamic imaging (BDI) uses low-coherence 3D digital holography to capture dynamic speckle fluctuations caused by the multiple interferences among Doppler frequencies. The omega-tau product provides a natural dividing line between Doppler and diffusive regimes, with a broad cross-over range into which many tissue-based light scattering processes fall. This talk describes the biophysical origins of fluctuation spectra from intracellular transport. Biodynamic imaging, based on changes in intracellular dynamics caused by applied therapeutics or changing environments, is expanding into multiple applications, including the selection of chemotherapy for personalized cancer care, screening of potential new therapeutics, and the selection of embryos for artificial reproductive technology. See https://works.bepress.com/ddnolte/.