Label-Free Measurements of Tenofovir Diffusion Coefficients in a Microbicide Gel Using Raman Spectroscopy.

ABSTRACT: Confocal Raman spectroscopy was implemented in a new label-free technique to quantify molecular diffusion coefficients within gels. A leading anti-HIV drug, tenofovir, was analyzed in a clinical microbicide gel. The gel was tested undiluted, and in 10%-50% wt/wt dilutions with vaginal fluid simulant to capture the range of conditions likely occurring in vivo. The concentration distributions of tenofovir in gel over time and space were measured and input to a mathematical diffusion model to deduce diffusion coefficients. These were 3.16 ± 0.11 × 10^-6 cm²/s in undiluted gel, and increased by 11%-46% depending on the extent of dilution. Results were interpreted with respect to traditional release rate measurements in devices such as Franz cells. This comparison highlight

SUBMITTER: Chuchuen O 

PROVIDER: S-EPMC5503201 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature