Quantification of the Uptake of Gold Nanoparticles in Cancer Cells Via High Order Image Correlation Spectroscopy

Abstract

The application of gold nanoparticles (AuNPs) in cancer therapeutics and diagnostics has recently reached to a clinical level. Functional use of the AuNP in theranostics first requires effective uptake into the cells, but accurate quantification of AuNPs cellular uptake in real-time is still a challenge due to destructive nature of existing characterization methods. Optical imaging-based quantification method is highly desirable. Here, we propose to use High-Order Image Correlation Spectroscopy (HICS) as an optical imaging-based nanoparticle quantification technique. Coupled with Dark Field Microscopy (DFM), a non-destructive and easy quantification method could be achieved. We demonstrate HICS analysis on 80 nm AuNPs coated with cetyltrimethylammonium bromide (CTAB) uptake in HeLa cells to calculate percentage of aggregate species (dimer) in the total uptake and their relative scattering quantum yield inside the cells, the details of which are not available with other quantification techniques. The total particle uptake kinetics measured were in a reasonable agreement with the literature.