Cytotoxicity of free or nanoparticulate flurbiprofen. bEnd.3 cells were treated with the indicated concentrations of free flurbiprofen (A) or PLA-flurbiprofen nanoparticles (B) for 72 hours. The cytotoxicity was assessed after a four hour incubation with 1 × alamarBlue®. The absorbance was measured and the cell viability was calculated as a percentage of absorbance in relation to vehicle control treated cells. The data represent mean ± SEM of n ≥3. PLA, polylactide; SEM, standard error of the mean.