Figure 3.

Already-validated CFMEA method and the proposed MESMER method differ only at their extraction step. In both assays, cells are “loaded” with Mn by an extracellular Mn concentration. After this incubation, this extracellular Mn is washed away so that only intracellular Mn remains. In the CFMEA method, PBS with 0.1% Triton is used to lyse open the cells and release intracellular Mn, and 0.5 μm Fura-2 is also present to act as a fluorescent Mn indicator. In contrast, the MESMER assay extracts Mn using a small molecule, VU0028386, or MESM, while also in the presence of Fura-2. The last step remains the same, as Mn is quantified by measuring the quenching of the Fura-2 signal at excitation/emission 360/535 nm.