Joint forces of direct, single particle, CE- and HPLC-inductively coupled plasma mass spectrometry techniques for the examination of gold nanoparticle accumulation, distribution and changes inside human cells.
Intracellular localization and transformation of gold nanoparticles (AuNPs) are one of the crucial aspects in terms of future application in cancer therapy. In the frame of the study, the inductively coupled plasma mass spectrometry (ICP-MS) based techniques were effectively applied to reveal the fate of AuNPs internalized into the cancerous MCF-7 cells. Direct ICP-MS was used to obtain the quantitative information about the distribution rate of gold from AuNPs in cells, namely their membranes, cytosol, as well as, nuclei. Moreover, the hyphenations of capillary electrophoresis and reversed-phase liquid chromatography with ICP-MS were probed and compared as tools for effective monitoring of the speciation changes of gold-containing forms in the cytosol. The chemical nature (ionic vs. nano) of metal detected in the cytosol was verified by ICP-MS in single-particle mode, confirming the stability of nanomaterial and no presence of ionic gold forms inside the cells.