Cell viability was measured using MTT colorimetric assay after treating the cells with different concentrations (2 and 0.5 μM) of DOX, PLGA–RhB–VCAM1, and PLGA–RhB (A, B). Cell viability decreased up to 29.29 and 50.31% with 2 and 0.5 μM of DOX treatment, respectively, after 8 h (A). The toxicity study of the nanoparticles shows that the PLGA–RhB–VCAM1 nanoparticle is relatively nontoxic to the cell; here, the study was done in cells without DOX exposure. Error bar represents mean ± SD, where n = 6.