High-performance thin-layer chromatography for the evaluation of voacamine intracellular concentration related to its cytotoxic effect.
Previous investigations demonstrated that pretreatment with non-cytotoxic concentrations of voacamine had a chemosensitizing effect on cultured multidrug resistant osteosarcoma cells exposed to doxorubicin whereas when used alone at high concentrations voacamine induced apoptosis-independent cell death on both sensitive and resistant cells. To gain insight into the mechanism of action of voacamine at the subcellular level, we developed an analytical high-performance thin-layer chromatography technique to assess the intracellular content of voacamine that could be correlated with the induction of cell death and consequent morphological and ultrastructural changes. The results of the quantitative analysis not only did allow us to measure both the amount of unmodified voacamine molecules (determined by the method) and the amount of molecules which reacted with cellular components (undetectable), but also to confirm the findings of our previous studies and support the validity of this method.