Multifunctional Core–Shell Upconverting Nanoparticles for Imaging and Photodynamic Therapy of Liver Cancer Cells

Abstract

Lanthanide-doped upconversion nanoparticles (UCNPs) have attracted considerable attention for their application in biomedicine. Here, silica-coated NaGdF(4):Yb,Er/NaGdF(4) nanoparticles with a tetrasubstituted carboxy aluminum phthalocyanine (AlC(4)Pc) photosensitizer covalently incorporated inside the silica shells were prepared and applied in the photodynamic therapy (PDT) and magnetic resonance imaging (MRI) of cancer cells. These UCNP@SiO(2)(AlC(4)Pc) nanoparticles were uniform in size, stable against photosensitizer leaching, and highly efficient in photogenerating cytotoxic singlet oxygen under near-infrared (NIR) light. In vitro studies indicated that these nanoparticles could effectively kill cancer cells upon NIR irradiation. Moreover, the nanoparticles also demonstrated good MR contrast, both in aqueous solution and inside cells. This is the first time that NaGdF(4):Yb,Er/NaGdF(4) upconversion-nanocrystal-based multifunctional nanomaterials have been synthesized and applied in PDT. Our results show that these multifunctional nanoparticles are very promising for applications in versatile imaging diagnosis and as a therapy tool in biomedical engineering.

Preparation and upconversion luminescence cell imaging of O-carboxymethyl chitosan-functionalized NaYF4:Yb3+/Tm3+/Er3+ nanoparticles

“…As depicted in Figure 3(a), the emission peaks of the as-prepared nanoparticles in the wavelength region of 300900 nm are assigned to the transitions of 1 respectively [21,36]. The inset of Figure 3(a) showed the corresponding red UC luminescence photographs of UCNPs dispersed in water.…”

Magnetic and fluorescent Gd₂O₃:Yb³⁺/Ln³⁺ nanoparticles for simultaneous upconversion luminescence/MR dual modal imaging and NIR-induced photodynamic therapy

“…A popular host material is NaYF 4 , which exhibits high upconversion efficiency due to the low phonon cutoff energy, 15 thus attracting much interest in UCNs-based PDT and upconversion luminescence (UCL) imaging. [16][17][18][19] Other fluorides containing Yb 3+ (NaYbF 4 ) and Gd 3+ (NaGdF 4 ) ions, which also function as computed tomography (CT) and magnetic resonance imaging (MRI) contrast agents, [20][21][22][23][24] have been utilized to achieve simultaneous dual-or multimodal bioimaging with high sensitivity and high spatial resolution. These multifunctional nanoparticles can satisfy the high efficiency and accuracy requirements of clinical cancer theranostics.…”

Upconversion nanoparticle as a theranostic agent for tumor imaging and therapy

“…76,115,[123][124][125][126][127][128] They used photosensitizer for PDT, and UCL or other imaging method for particle/tumor localization. The integration improves the treatment e®ects and gives a promising biomedicine application strategy.…”