P. Dorenbos - Academia.edu (original) (raw)
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Papers by P. Dorenbos
Using spectroscopic data on lanthanide ions in Al x Ga 1Àx N (0 6 x 6 1) and recently developed m... more Using spectroscopic data on lanthanide ions in Al x Ga 1Àx N (0 6 x 6 1) and recently developed methods, the 4f ground state energy for each divalent and trivalent lanthanide relative to the valence and conduction band is established. The obtained energy level schemes provide a complete description of relevant optical and luminescence properties of lanthanide doped Al x Ga 1Àx N (0 6 x 6 1). Especially, the relation between thermal quenching of Eu 3+ or Tb 3+ emission and the location of the energy levels is explained. The schemes reveal which trivalent lanthanide ions are able to trap electrons in their 4f-shell and which lanthanide ions are potential hole traps.
Optical Materials, 2010
We will provide a method to place the levels of all trivalent lanthanides with respect to the top... more We will provide a method to place the levels of all trivalent lanthanides with respect to the top of the valence band and bottom of the conduction band in oxides containing transition metal complexes. The method will be applied to CaTiO 3 , YVO 4 , LaVO 4 , CaNb 2 O 6 , YNbO 4 , CaWO 4 , YTaO 4 , and LaTaO 4 , but in principle can be applied to any oxide containing transition metal complexes with lanthanide dopants on either rare earth or alkaline earth sites. Crucial to place the energy levels is the energy for intervalence charge transfer between a lanthanide (Pr 3þ and Tb 3þ ) and a transition metal ion (Ti 4þ ; V 5þ ; Nb 5þ ; Mo 6þ ; Ta 5þ ; W 6þ ) that can be observed in luminescence excitation spectra. The quenching of Pr 3þ emission from the 3 P 0 state and of Tb 3þ emission from the 5 D 3 and 5 D 4 states provides complementary information.
Optical imaging for biological applications requires more sensitive tools. Near-infrared persiste... more Optical imaging for biological applications requires more sensitive tools. Near-infrared persistent luminescence nanoparticles enable highly sensitive in vivo optical detection and complete avoidance of tissue autofluorescence. However, the actual generation of persistent luminescence nanoparticles necessitates ex vivo activation before systemic administration, which prevents long-term imaging in living animals. Here, we introduce a new generation of optical nanoprobes, based on chromiumdoped zinc gallate, whose persistent luminescence can be activated in vivo through living tissues using highly penetrating lowenergy red photons. Surface functionalization of this photonic probe can be adjusted to favour multiple biomedical applications such as tumour targeting. Notably, we show that cells can endocytose these nanoparticles in vitro and that, after intravenous injection, we can track labelled cells in vivo and follow their biodistribution by a simple whole animal optical detection, opening new perspectives for cell therapy research and for a variety of diagnosis applications.
Using spectroscopic data on lanthanide ions in Al x Ga 1Àx N (0 6 x 6 1) and recently developed m... more Using spectroscopic data on lanthanide ions in Al x Ga 1Àx N (0 6 x 6 1) and recently developed methods, the 4f ground state energy for each divalent and trivalent lanthanide relative to the valence and conduction band is established. The obtained energy level schemes provide a complete description of relevant optical and luminescence properties of lanthanide doped Al x Ga 1Àx N (0 6 x 6 1). Especially, the relation between thermal quenching of Eu 3+ or Tb 3+ emission and the location of the energy levels is explained. The schemes reveal which trivalent lanthanide ions are able to trap electrons in their 4f-shell and which lanthanide ions are potential hole traps.
Optical Materials, 2010
We will provide a method to place the levels of all trivalent lanthanides with respect to the top... more We will provide a method to place the levels of all trivalent lanthanides with respect to the top of the valence band and bottom of the conduction band in oxides containing transition metal complexes. The method will be applied to CaTiO 3 , YVO 4 , LaVO 4 , CaNb 2 O 6 , YNbO 4 , CaWO 4 , YTaO 4 , and LaTaO 4 , but in principle can be applied to any oxide containing transition metal complexes with lanthanide dopants on either rare earth or alkaline earth sites. Crucial to place the energy levels is the energy for intervalence charge transfer between a lanthanide (Pr 3þ and Tb 3þ ) and a transition metal ion (Ti 4þ ; V 5þ ; Nb 5þ ; Mo 6þ ; Ta 5þ ; W 6þ ) that can be observed in luminescence excitation spectra. The quenching of Pr 3þ emission from the 3 P 0 state and of Tb 3þ emission from the 5 D 3 and 5 D 4 states provides complementary information.
Optical imaging for biological applications requires more sensitive tools. Near-infrared persiste... more Optical imaging for biological applications requires more sensitive tools. Near-infrared persistent luminescence nanoparticles enable highly sensitive in vivo optical detection and complete avoidance of tissue autofluorescence. However, the actual generation of persistent luminescence nanoparticles necessitates ex vivo activation before systemic administration, which prevents long-term imaging in living animals. Here, we introduce a new generation of optical nanoprobes, based on chromiumdoped zinc gallate, whose persistent luminescence can be activated in vivo through living tissues using highly penetrating lowenergy red photons. Surface functionalization of this photonic probe can be adjusted to favour multiple biomedical applications such as tumour targeting. Notably, we show that cells can endocytose these nanoparticles in vitro and that, after intravenous injection, we can track labelled cells in vivo and follow their biodistribution by a simple whole animal optical detection, opening new perspectives for cell therapy research and for a variety of diagnosis applications.