PCR quantification of SiO₂ particle uptake in cells in the ppb and ppm range via silica encapsulated DNA barcodes.

There is a strong interest in studying the cellular uptake of silica nanoparticles, particularly at medically relevant concentrations (ppb-ppm range) to understand their toxicology. At present, uptake analysis at these exposure levels is impeded by the high silica background concentration. Here we describe the use of DNA encapsulated within silica particles as a tool to quantify silica nanoparticles in in vitro cell-uptake experiments at low concentrations (down to 10 fg cell(-1)).