Evaluating Cytotoxicity of PAMAM Dendrimers

BMDCs were seeded at a density of 1 × 10⁴ cells per well in a 96-well plate in 180 μl per well of complete RPMI 1640 cell culture media. After incubation for a few hours, cells were treated with an increasing concentration of PMG5 (50, 100, 200, 400, 800, and 1600 μg/ml). Also, corresponding concentrations of soluble PAMAM G5 (6.25, 12.50, 25, 50, 100, and 200 μg/ml) were tested. Plates were then incubated at 37°C with 5% CO₂ for 48 hours. Next, Cell Titer 96 aqueous MTS reagent [3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide, purchased from Promega Corporation, San Luis Obispo, CA] was added to the cells following the manufacturer’s instructions (63 (link), 68 –70 (link)). After incubation for 2 hours, cell viability (%) was calculated on the basis of the absorbance measured at 490 nm using a SpectraMax Plus spectrophotometer (Molecular Devices, San Jose, CA).