Red‐Emitting Upconverting Nanoparticles for Photodynamic Therapy in Cancer Cells Under Near‐Infrared Excitation

Abstract

Upconverting nanoparticles (UCNPs) have attracted considerable attention as potential photosensitizer carriers for photodynamic therapy (PDT) in deep tissues. In this work, a new and efficient NIR photosensitizing nanoplatform for PDT based on red-emitting UCNPs is designed. The red emission band matches well with the efficient absorption bands of the widely used commercially available photosensitizers (Ps), benefiting the fluorescence resonance energy transfer (FRET) from UCNPs to the attached photosensitizers and thus efficiently activating them to generate cytotoxic singlet oxygen. Three commonly used photosensitizers, including chlorine e6 (Ce6), zinc phthalocyanine (ZnPc) and methylene blue (MB), are loaded onto the alpha-cyclodextrin-modified UCNPs to form Ps@UCNPs complexes that efficiently produce singlet oxygen to kill cancer cells under 980 nm near-infrared excitation. Moreover, two different kinds of drugs are co-loaded onto these nanoparticles: chemotherapy drug doxorubicin and PDT agent Ce6. The combinational therapy based on doxorubicin (DOX)-induced chemotherapy and Ce6-triggered PDT exhibits higher therapeutic efficacy relative to the individual means for cancer therapy in vitro.

Upconversion nanoparticle-mediated photodynamic therapy induces THP-1 macrophage apoptosis via ROS bursts and activation of the mitochondrial caspase pathway

“…7 PDT has also been used to treat cardiovascular pathologies, including AS and restenosis, 8,9 and our group previously testified that 5-aminolevulinicacid-mediated PDT both decreases macrophage content and inhibits plaque progression in rabbit carotid artery AS models. 10 However, a drawback of conventional therapy is the requirement of direct illumination of the tissue by either visible (VIS) or ultraviolet (UV) light to excite the photosensitizers, which have limited penetration depth due to both the absorption and scattering of light by biological tissues, thereby resulting in ineffective therapeutic effects.…”

pH-Sensitive self-assembling nanoparticles for tumor near-infrared fluorescence imaging and chemo–photodynamic combination therapy

“…S2(B), ESI †) of Ce6. 35 The final product was filtered through a 0.45 µm pore-size microporous membrane. The Entrapment Efficiency (EE) and Drug-Loading (DL) capacity were calculated using the following equations:…”

A Hollow NaGdF4/AFn Nanosystem Based on “Relay Race” Release for Therapy

“…[27][28][29][30] The cytotoxicity of NaGdF 4 -AFn-FA was therefore studied by using standard 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays with the MCF-7 cell line, and the results are shown in Figure 4A.M CF-7 cells were incubated with variousN aGdF 4 -AFn-FAc oncentrations, ranging from 6.25 to 200 mgmL…”