Figure 5.

Cytotoxic effect of investigated compounds: (a) AlaSal, (b) Co(II)–AlaSal complexes (c) Co(II) alone towards L929 cells. The cytotoxicity was assessed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)] reduction assay. The cell viability was calculated for four experiments including three repeats for each compound. Complete RMPI-1640 medium (cRPMI) was used as a positive control (C+) of cell viability (100% viable cells) and 0.03% H₂O₂ as a negative control (C⁻) of cell viability (100% dead inactive cells). Statistical significance: *•■ p < 0.05; * untreated cells vs. cells treated with tested solution (solution prepared directly); • untreated cells vs. cells treated with tested solution (solution stored for two weeks) ■ solution prepared directly vs. solution stored for two weeks.