Comparative evaluation of nano and bulk tin dioxide cytotoxicity on dermal fibroblasts by real-time impedance-based and conventional methods

Abstract

In this study, the possible cellular effects of tin dioxide ($SnO_2$) nanoparticles, together with its bulk form, on mouse dermalfibroblasts (DFs) were revealed using in vitro assays. Particle characterizations were carried out with AFM, Braun–Emmet–Teller, andDLS analyses. The cells were treated with nano and bulk $SnO_2$ at concentrations of 0.1, 1, 10, 50, and 100 μg/mL for 6, 24, and 48 h. Atthe end of the exposure periods, the morphology, viability, particle uptake, and membrane leakage statuses of the cells were evaluated.Furthermore, real-time monitoring of cell responses was performed by using an impedance-based label-free system. Findings showedthat at concentrations of 0.1–10 μg/mL, cells had similar doubling time to that of control cells (20.4 ± 2.6 h), while the doubling time ofcells exposed to 100 μg/mL of nano and bulk $SnO_2$ increased slightly (P ˃ 0.05) to 25.1 ± 3.9 h and 26.2 ± 5.9 h, respectively. The resultsindicated that DFs exhibited a similar toxicity response to nano and bulk $SnO_2$; thus, 50 and 100 μg/mL of nano and bulk $SnO_2$ hadmild toxic effects on DFs. In conclusion, this study provides information and insight necessary for the safe use of $SnO_2$ in medical andconsumer products.