Thermo x series quadrupole icp ms

For the cellular uptake experiments, A375 human melanoma cells (ca. 1 × 10⁶ cells/5 mL) were seeded into t25 flasks and allowed to adhere overnight in a 5% CO₂ incubator at 37 °C. Cells settled for 24 h, followed by the addition of RuCB1 and RuCB2, at a concentration equivalent to their IC₅₀ values found for 24 h challenge at 37 °C. After incubation, cells were washed with ice-cold PBS and treated in order to obtain a cellular pellet. The cytosol, membranes/particulate, cytoskeletal and nuclear fractions were extracted using a FractionPREP™ (BioVision, USA) cell fractionation kit according to the manufacturer's protocol. The Ru (¹⁰²Ru) and B (¹⁰B) content in each fraction was measured by a Thermo X-Series Quadrupole ICPMS (Thermo Scientific) after digestion of the samples and using a procedure similar to a previously described.^{76 (link)}