2.7 Cytotoxic effects of nanoreactors
Breast tumor cell cytotoxic effects of GOx nanoreactors were studied by means of an in vitro assay. Two cell lines were exposed to different nanoreactor amounts. First, human embryonic kidney (293T) as a human healthy cell model; second 4T1 (murine breast cancer tumor). The nanoreactor-exposed cells were analyzed by an MTT colorimetric assay (TOX-1, Sigma-Aldrich, St. Louis, MO) to estimate the cytotoxic effect. Firstly, the cells were cultured in 96 well-plates; for 293T, 10,000 cells/well; for 4T1, 4,000 cells/well at 37°C and 5% CO2. After 24 h, the cells were treated with different nanoreactor amounts. Finally, 48 h later starting the cultures, the MTT reagent (methyl-134-thiazolyl-tetrazolium) was added to the cells, and the absorbance (570 nm) showed in the well-plate was measured with a Multiskan GO spectrophotometer (Thermo Scientific). The resulting absorbance from negative control (cell media) was established as 100% of cell survival. Then, experimental groups were compared to estimate a survival rate.