Characterization of quantum dots in cancer cytosol using ICP-MS-based combined techniques.

Knowledge of the intracellular behavior of quantum dots (QDs), which encompasses the antiproliferative effect on living cells, is still limited. For this reason, the transformations of CdSeS/ZnS-based QDs in cancer cytosol were examined using capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC) hyphenated with inductively coupled plasma MS (ICP-MS). CE-ICP-MS method revealed the dose- and time-dependent speciation changes of QDs in the cytosol, while HPLC-ICP-MS (in the size-exclusion chromatography mode) allowed further characterization of the resulting Cd species. In such an appraisal, the decent CE advantage of high resolution is well complemented by higher sensitivity of HPLC (LOD 4.0 × 10-10 and 5.4 × 10-12 mol/L Cd, respectively). Additionally, the influence of serum protein corona on the surface of QDs on their uptake by Hep G2 cancer cells was investigated by direct ICP-MS analysis that revealed that the conjugated proteins greatly reduce the particle internalization.