Single cell analysis for elucidating cellular uptake and transport of cobalt curcumin complex with detection by time-resolved ICPMS.

It is of great importance to elucidate the fate of drugs, e.g., their cellular uptake, transport and metabolism/excretion at single cell level. In the present work, cellular uptake and excretion of curcumin in HepG2 and MCF-7 cells were investigated by measuring 59Co in a curcumin cobalt complex ([Co(tpa)(cur)](ClO4)2) with inductively coupled plasma mass spectrometry (ICPMS). The uptake and distribution pattern of the metal drug complex in single cells were thoroughly studied, demonstrating extremely large discrepancy of uptake behavior among individual cells. The complex concentration-dependent uptake and excretion behavior is observed for both HepG2 and MCF-7 cells. The uptake of ([Co(tpa)(cur)](ClO4)2) by HepG2 cells is firstly increased with the concentration of the complex followed by level-off at certain level. On the other hand, however, the uptake by MCF-7 cells increases exponentially with the complex concentration within a same concentration range. The present study provides important information on the transport process of the metal drug complex at single cell level, it may be promising for further applications in the elucidation of metal drug effectiveness in vivo.