Tenofovir concentration vs.

<div><p><b>depth in tissue in the </b></p> <p><b>Transwell assay</b>. </p> <p>Confocal Raman scans were performed on tissue specimens that had been incubated under a fluid layer (containing 1% Tenofovir) in the Transwell assay for 6 h (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0085124#pone-0085124-g010" target="_blank">Figure 10</a>). After baseline correction, the intensity of the Tenofovir Raman band was normalized with respect to the intensity of the tissue band at 643 cm^-1. Normalized intensities were background-subtracted and fitted into a respective calibration curve of Tenofovir in tissue homogenate to deduce the concentration vs. depth profiles. The Raman measurements showed a decline in concentration as the depth into the tissue increased. Data shown give mean ± standard error of the mean (n=7). </p>