Decoupling Theranostics with Rare Earth Doped Nanoparticles

Abstract

Theranostic nanoagents targeted for personalized medicine provide a unified platform for therapeutics and diagnostics. To be able to discretely control each individually, allows for safer, more precise, and truly multifunctional theranostics. Rare earth doped nanoparticles can be rationally tailored to best match this condition with the aid of core/shell engineering. In such nanoparticles, the light‐mediated theranostic approach is functionally decoupled—therapeutics or diagnostics are prompted on‐demand, by wavelength‐specific excitation. These decoupled rare earth nanoparticles (dNPs) operate entirely under near‐infrared (NIR) excitation, for minimized light interference with the target and extended tissue depth action. Under heating‐free 806 nm irradiation, dNPs behave solely as high‐contrast NIR‐to‐NIR optical markers and nanothermometers, visualizing and probing the area of interest without prompting the therapeutic effect beforehand. On the contrary, 980 nm NIR irradiation is upconverted by the dNPs to UV/visible light, which triggers secondary photochemical processes, e.g., generation of reactive oxygen species by photosensitizers coupled to the dNPs, causing damage to cancer cells. Additionally, integration of NIR nanothermometry helps to control the temperature in the vicinity of the dNPs avoiding possible overheating and quenching of upconversion (UC) emission, harnessed for photodynamic therapy. Overall, a new direction is outlined in the development of state‐of‐the‐art rare earth based theranostic nanoplatforms.

Rational Design of Ratiometric Luminescence Thermometry Based on Thermally Coupled Levels for Bioapplications

“…After then, NIR‐to‐NIR nanothermometers LiYF 4 :Nd 3+ coated with Amphiphilic chlorin e 6 photosensitizer were constructed with the improved sensitivity of 0.22% K –1 , where the cellular temperature was controlled to avoid overheating effects during the photodynamic therapy. [ 161 ] Recently, NIR emissions around 1050 nm (BW‐II) of CaF 2 :Nd 3+ , Y 3+ NPs were reported by Quintanilla et al. for real‐monitoring the temperature of gold nanorods in deep tissues under 808 nm excitation, where the incorporation of Y 3+ ions improved both NIR intensity and thermal sensitivity.…”

Wavelength‐Dependent Singlet Oxygen Generation in Luminescent Lanthanide Complexes with a Pyridine‐Bis(Carboxamide)‐Terthiophene Sensitizer

“…A NP doped with Yb III , Er III , and Tm III was decorated with a 1 O 2 ‐generating bacteriochlorin derivative and an orange‐emitting 1,8‐naphthalimide derivative; it could be selectively excited in the NIR for safer tracking . In addition, a NP with an Yb III /Tm III ‐doped core and a Nd III ‐containing shell was explored for its functionality as a 1 O 2 generator, and as an optical contrast agent and nanothermometer, using NIR luminescence …”

Multifunktionale Einzelmolekülmagnete auf Lanthanoidbasis in neuem Licht

“…Ungeachtet dessen war dies das erste Beispiel eines SMM auf der Basis von Yb 3+ ,d er das Potenzial fürd ie Lumineszenz-Thermometrie hat. Wirmçchten auch die Verwendung eines im NIR emittierenden Ions hervorheben, was eine äußerst wünschenswerte Eigenschaft bei biologischen Anwendungen ist, [134,135] die den Wegf ürw eitere Untersuchungen in dieser Richtung ebnet. In einer zweiten Studie erreichten wir eine vollständige Harmonisierung der magnetischen Eigenschaften und der Lumineszenzeigenschaften, indem eine Überlappung der Bereiche der langsamen magnetischen Relaxation und der Lumineszenz-Thermometrie realisiert wurde.…”