Semiconductor Nanoplatelets as Ultra-Bright Fluorophores for Two-Photon Absorption Cell Imaging br

The development of new two-photon fluorescent probes is desirable for imaging in biosystems. Semiconductor CdSe nanoplatelets are promising candidates for this purpose due to their large absorption cross sections, extremely narrow photolumines-cence emission, and high spectral brightness. Herein, we obtained water dispersible nanoplatelets (poly-NPLs) and explored their potential for intracellular imaging using commercially available Qdot 655 CdSe-based quantum dots as a control. Comparison was carried out for one- and two-photon imaging. The emission of poly-NPLs was found to be consistently higher than the one of Qdot 655at equal particle concentrations as well as at equal cadmium concentrations for both one-photon and two-photon excitations. In particular, poly-NPLs can show up to 3 orders of magnitude higher fluorescence brightness compared to Qdot 655 when excited with two-photons, which makes them interesting candidates for multiphoton imaging and single molecule detection applications