Presentation Description: This research examines the hypothesis that Raman spectroscopy offers a non-invasive and reproducible method for evaluating the bioavailability (BA) of a topically applied drug in the skin. Raman spectra were acquired with a Renishaw inVia microscope. Experiments were performed ex vivo using pig skin and three formulations (two saturated and one 25% saturated) of 4-cyanophenol (CP), which has a strong Raman signal (-C≡N vibration), in a region where the skin is spectroscopically ‘transparent’. CP disposition was assessed, as functions of skin depth and duration of dose application. The saturated formulations produced very similar profiles across the skin; when the degree of saturation was reduced to 25%, the CP profile adjusted proportionally. Overall, the Raman-based approach was able to track drug permeation to skin depths of at least 100 µm, and to compare and differentiate drug delivery from different formulations; signal attenuation due to absorption and/or scattering was mitigated by normalization.
Upon completion, participant will be able to consider Raman spectroscopic as a tool for the evaluation of skin pharmacokinetics.
Upon completion, participant will be able to consider Raman spectroscopic as a surrogate method to assess bioequivalence/bioavailability of topical drug products.
Upon completion, participant will be able to understand how to use Raman spectroscopic to track drug penetration and clearance to and from the skin.