Cobalt Chloride Induced Hypoxia in OCCM-30 Cells

For hypoxic experiments, OCCM-30 cells were cultivated supplemented with 100 μM or 400 μM cobalt (II) chloride hexahydrate (CoCl₂) for indicated time periods to mimick the different hypoxic culture conditions [28 (link)]. Briefly, CoCl₂ (C8661, Sigma-Aldrich, Taufirchen, Germany) was dissolved directly to the growth medium and sterilized through a sterile 0.2 μm spare membrane filter (Z333905-1EA, Merck, Darmstadt, Germany) to reach final concentrations of 100 μM or 400 μM. These concentrations are based on the hypoxic concentration established in previous studies [22 (link),28 (link)]. Cells cultured without CoCl₂ served as the normoxic control.