Nonlinear laser scanning microscopy for imaging of the cells labeled by upconverting NaYF4:Yb,Er nanoparticles

Abstract

The Nonlinear Laser Scanning Microscopy (NLSM) contributes to the cell labeling through addressing two main issues: photobleaching and phototoxicity. Moreover, an increase of the penetration depth and a reduction of background autofluorescence are achieved.We have used a multidisciplinary approach combining expertise in material science, nanoparticles synthesis and characterization, cancer cell and tissue labeling, and high resolution imaging, in order to accomplish in vitro imaging of the cancer cells. We have imaged the oral squamous carcinoma cells and human gingival cells. We have demonstrated that we are able to take high contrast images. We have shown position of the nanoparticles in cells, through colocalization of the cell auto-fluorescence and the nanoparticles up-conversion.We plan to improve our abilities through further optimization of the up-converting nanoparticles (smaller and brighter particles) and microscopy technique.