Optical Coherence Elastography—A Novel Non-Invasive Optical Method for Real-Time Determination of Substances Penetration and Associated Skin Dehydration

Non-invasive, in vivo assessment of target substances penetration into the skin remains a significant challenge in dermatology and cosmetology. While various optical methods have been employed for this purpose, each has inherent limitations. Here, we present a novel non-invasive imaging approach using optical coherence elastography (OCE) to simultaneously determine the penetration depth of topically applied osmotically active substances in biological objects and associated water content changes with high sensitivity. Most substances are osmotically active and generate osmotic pressure proportional to their concentration, inducing deformations in biological objects. These osmotic strains can be visualized similarly to mechanical or thermal strains. Using OCE, we evaluated penetration and dehydration depth profiles in polyacrylamide gel phantoms, ex vivo cartilage, and porcine ear skin samples treated with aqueous glycerol solutions of varying concentrations. Additionally, the penetration and effect of jojoba oil were assessed in treated skin samples. The results are consistent with those obtained by other established methods, confirming the reliability and applicability of OCE. This technique offers unique capabilities not achievable with other optical methods, making it a valuable complementary tool for non-invasive studies. It holds significant promise for advancing both research and clinical applications in dermatology and cosmetology, including its potential translation to in vivo assessments.