Molecular Diffusion and Optical Properties of Implantable Collagen Materials

The effects of optical clearing of implantable collagen materials were studied using optical clearing agents (OCAs) based on aqueous glucose solutions of various concentrations. By measuring the kinetics of the collimated transmission spectra, the diffusion D and permeability P coefficients of the OCAs of collagen materials were determined as D = (0.22 ± 0.05) × 10^-6 to (1.41 ± 0.05) × 10^-6 cm²/c and P = (0.55 ± 0.04) × 10^-4 to (1.77 ± 0.07) × 10^-4 cm/c. Studies with optical coherence tomography (OCT) confirmed that each of the OCAs used had an effect on the optical properties of collagen materials, and allowed us to quantify the group refractive indices of the collagen of various samples, which turned out to be in the range from n_c = 1.476 to n_c = 1.579.