Spontaneous confocal Raman microscopy--a tool to study the uptake of nanoparticles and carbon nanotubes into cells
1 CIC biomaGUNE, Paseo Miramón 182 C, 20009 San Sebastian, Spain
2 Institute of Biophysics and Medical Physics, University of Leipzig Härtelstraße 16-18, D-04107 Leipzig, Germany
Nanoscale Research Letters 2011, 6:429 doi:10.1186/1556-276X-6-429Published: 16 June 2011
Confocal Raman microscopy as a label-free technique was applied to study the uptake and internalization of poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) and carbon nanotubes (CNTs) into hepatocarcinoma human HepG2 cells. Spontaneous confocal Raman spectra was recorded from the cells exposed to oxidized CNTs and to PLGA NPs. The Raman spectra showed bands arising from the cellular environment: lipids, proteins, nucleic acids, as well as bands characteristic for either PLGA NPs or CNTs. The simultaneous generation of Raman bands from the cell and nanomaterials from the same spot proves internalization, and also indicates the cellular region, where the nanomaterial is located. For PLGA NPs, it was found that they preferentially co-localized with lipid bodies, while the oxidized CNTs are located in the cytoplasm.