Optical sensing of macromolecules and microparticles distribution in tissues

This paper describe a highly systematic set of experiments demonstrating capability of Optical Coherence Tomography (OCT) technique for depth-resolved, real-time and truly noninvasive analysis of complex diffusion processes of macromolecules in epithelial and vascular tissues as well to image and detect magnetic microparticles (stationary and moving) under the skin with single-particle sensitivity. For example, we demonstrate that the permeation of VLDL, LDL, HDL, and glucose in normal and diseased human carotid endarterectomy tissues could be quantified that supported previous suggestions of an enhanced transport mechanism specific to LDL. Additionally, we investigated sensitivity of OCT to assess magnetic microbead (d=2.8 um) count under the skin, which could the basis for development of continuous glucose sensing platform.