10.1021/acs.nanolett.6b00502.s001 Hannelore Bové Hannelore Bové Christian Steuwe Christian Steuwe Eduard Fron Eduard Fron Eli Slenders Eli Slenders Jan D’Haen Jan D’Haen Yasuhiko Fujita Yasuhiko Fujita Hiroshi Uji-i Hiroshi Uji-i Martin vandeVen Martin vandeVen Maarten Roeffaers Maarten Roeffaers Marcel Ameloot Marcel Ameloot Biocompatible Label-Free Detection of Carbon Black Particles by Femtosecond Pulsed Laser Microscopy American Chemical Society 2016 WL emission CB particles illumination Carbon Black Particles fluid detection Femtosecond Pulsed Laser Microscopy 2016-04-22 11:50:08 Journal contribution https://acs.figshare.com/articles/journal_contribution/Biocompatible_Label_Free_Detection_of_Carbon_Black_Particles_by_Femtosecond_Pulsed_Laser_Microscopy/3189058 Although adverse health effects of carbon black (CB) exposure are generally accepted, a direct, label-free approach for detecting CB particles in fluids and at the cellular level is still lacking. Here, we report nonincandescence related white-light (WL) generation by dry and suspended carbon black particles under illumination with femtosecond (fs) pulsed near-infrared light as a powerful tool for the detection of these carbonaceous materials. This observation is done for four different CB species with diameters ranging from 13 to 500 nm, suggesting this WL emission under fs near-infrared illumination is a general property of CB particles. As the emitted radiation spreads over the whole visible spectrum, detection is straightforward and flexible. The unique property of the described WL emission allows optical detection and unequivocal localization of CB particles in fluids and in cellular environments while simultaneously colocalizing different cellular components using various specific fluorophores as shown here using human lung fibroblasts. The experiments are performed on a typical multiphoton laser-scanning microscopy platform, widely available in research laboratories.