Background and Aims: Although metal and metal oxide nanoparticles are used in different medical applications, they may have considerable toxicity on various cells, such as myocytes. Therefore, this study aimed to evaluate the toxicity of the naked and serum-treated silver nanoparticles (Ag NPs) and magnesium oxide nanoparticles (MgO NPs) on the cardiomyocytes.

Materials and Methods: Cardiomyocytes were separately exposed to different concentrations of the naked and serum-treated nanoparticles for 24 hours at 37ºC. Then, MTT assay, cell metabolism assay and LDH assay were performed.

Results: Naked Ag NPs and MgO NPs had more toxicity than serum-treated nanoparticles. The highest cardiomyocyte toxicity was observed for naked Ag NPs, whereas the minimum toxicity was seen for the serum-treated MgO NPs.

Conclusions: Coating of nanoparticles with serum components leads to decrease in toxicity for cardiomyocytes, and MgO NPs have less toxicity on the myocytes than Ag NPs.