Modulation of Tissue Optical Properties through Lipid Disruption and Refractive Index Matching

Light scattering limits how deeply we can image into living tissue. A major source of this scattering is the mismatch in refractive index between lipid-rich structures and surrounding aqueous regions, which causes photons to deviate as they cross microscopic boundaries. We investigate a transient clearing strategy that couples two mechanisms: surfactants that disrupt lipid bilayers, reducing the density of scattering sites, and the absorbing dye tartrazine, which alters the refractive index of the interstitial medium to promote improved optical matching. To evaluate these effects, we use a controlled illumination-detection setup to monitor changes in light transmission over time, showing how lipid disruption and index tuning together alter bulk photon transport. These results demonstrate that specific chemical agents can be used to actively modulate scattering and absorption, establishing a phsyics-based pathway toward accelerated transparency and deeper in vivo optical access