In this study, we report on the remarkable two-photon excited fluorescence efficiency in the "biological window" of CaF2:Tm3+,Yb3+ nanoparticles. Based on the strong Tm3+ ion emission (at around 800 nm), tissue penetration depths as large as 2 mm have been demonstrated, which are more than four times those achievable based on the visible emissions in comparable CaF2:Er3+,Yb3+ nanoparticles. The outstanding penetration depth, together with the fluorescence thermal sensitivity demonstrated here, makes CaF2:Tm3+,Yb3+ nanoparticles ideal candidates as multifunctional nanoprobes for high contrast and highly penetrating in vivo fluorescence imaging applications.
NIR-to-NIR two-photon excited CaF2:Tm3+,Yb3+ nanoparticles: multifunctional nanoprobes for highly penetrating fluorescence bio-imaging.
PEDRONI, Marco;PICCINELLI, FABIO;CONTI, GIAMAICA;SBARBATI, Andrea;BETTINELLI, Marco Giovanni;SPEGHINI, Adolfo
2011-01-01
Abstract
In this study, we report on the remarkable two-photon excited fluorescence efficiency in the "biological window" of CaF2:Tm3+,Yb3+ nanoparticles. Based on the strong Tm3+ ion emission (at around 800 nm), tissue penetration depths as large as 2 mm have been demonstrated, which are more than four times those achievable based on the visible emissions in comparable CaF2:Er3+,Yb3+ nanoparticles. The outstanding penetration depth, together with the fluorescence thermal sensitivity demonstrated here, makes CaF2:Tm3+,Yb3+ nanoparticles ideal candidates as multifunctional nanoprobes for high contrast and highly penetrating in vivo fluorescence imaging applications.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.