Neodymium-doped nanoparticles for infrared fluorescence bioimaging: The role of the host

Abstract

The spectroscopic properties of different infrared-emitting neodymium-doped nanoparticles (LaF 3 :Nd 3þ , SrF 2 :Nd 3þ , NaGdF 4 : Nd 3þ , NaYF 4 : Nd 3þ , KYF 4 : Nd 3þ , GdVO 4 : Nd 3þ , and Nd:YAG) have been systematically analyzed. A comparison of the spectral shapes of both emission and absorption spectra is presented, from which the relevant role played by the host matrix is evidenced. The lack of a "universal" optimum system for infrared bioimaging is discussed, as the specific bioimaging application and the experimental setup for infrared imaging determine the neodymiumdoped nanoparticle to be preferentially used in each case. V C 2015 AIP Publishing LLC.

Neodymium‐Based Stoichiometric Ultrasmall Nanoparticles for Multifunctional Deep‐Tissue Photothermal Therapy

“…[26] At this point it should be noted that, although the same diode laser was used in both cases, for experiments involving the Nd:LaF3 NPs the diode wavelength was temperature tuned down to 802 nm in order to increase the optical absorption of Nd:LaF3 NPs (whose absorption spectrum peaks at 790 nm). [27] As we mentioned before, Nd:LaF3 NPs have been successfully used as therapeutic photothermal agents, however, their heating curve has a less pronounced slope (below 5 ºC·cm 2 ·W -1 ). [15a, 16] It is important to note that the heating efficiency of Nd:LaF3 NPs would be about 80% higher if the excitation wavelength matched the absorption peak (≈ 789 nm).…”

Revisiting the classification of NIR-absorbing/emitting nanomaterials for in vivo bioapplications

“…163 This is especially true for NPs where both the sensitizer and activator ions are susceptible to surface quenching. 164 Fortunately, lanthanide materials also have valuable Stokes emissions in the NIR spectral regions (Figures 12a-c), 165 which have been used for imaging in the NIR biological transmission window NIR, 166,167 in intentional light-to-heat and heat-totemperature [168][169][170][171] readout features in single (Figure 12d) or hybrid NP-based 'devices'. There are numerous comprehensive review articles of the physics, spectroscopy and biomedical applications or nanotoxicity of lanthanide-doped NPs, and thus the readers are referred to these articles for further information.…”

Nd 3+ ions in nanomedicine: Perspectives and applications

“…Three absorption bands, centered at around 730, 800 and 865 nm, can be clearly observed. The spectral positions of these bands, which correspond to transitions from the ground state ( 4 I 9/2 ) to the 4 F 7/2 , 4 F 5/2 and 4 F 3/2 excited states of Nd 3þ ions, does not vary greatly when embedding Nd 3þ ions in other host nanocrystals [29]. At these excitation wavelengths, water absorption is minimum and so the overheating effect is strongly reduced.…”