Figure 3. Raman spectra for clinical 1% Tenofovir (TFV) gel.

Fresh porcine buccal tissue specimens (7-mm diameter, 1-mm thickness) were incubated by fully submerging them in 1% Tenofovir test gel (solid line) and HEC placebo gel (dotted line) for 6 h at 37°C and 5% CO₂ in a Heracell incubator. The recorded Raman spectra demonstrated that the Tenofovir band was clearly distinguishable from Raman peaks due to the gel and tissue. β, bending; ν, stretching ; τ, twisting; r, rocking.