Upconversion-Magnetic Carbon Sphere for Near Infrared Light-Triggered Bioimaging and Photothermal Therapy

Abstract

Nanoparticle-based theranostics combines tumor imaging and cancer therapy in one platform, but the synthesis of theranostic agents is impeded by chemical groups on the surface and the size and morphology of the components. Strategies to construct a multifunctional platform for bioimaging and photothermal therapy (PTT) are urgently needed. A new upconversion-magnetic agent (FeCUPs) based on hollow carbon spheres, which is both a photothermal agent and a dual carrier of luminescent and magnetic nanoparticles, provides an effective approach for tumor elimination. Methods: The morphology of FeCUPs was characterized for the construction and size adjustment of the theranostic agent using transmission electron microscopy, high-resolution transmission electron microscopy, energy dispersive spectroscopy and high angle annular dark field scanning transmission electron microscopy. The distribution of FeCUPs was tracked under in-situ upconversion luminescence (UCL) imaging and magnetic resonance imaging (MRI) in vivo . Photothermal therapy was carried out on tumor-bearing mice, after which the toxicity of PTT was evaluated by a blood biochemistry test and histological section analysis. Results: Stable and uniform loading of luminescent nanocomposites on three-dimensional carbon materials is reported for the first time. Based on the mechanism of synthesis, the size of the hybrid particles was adjusted from micrometers to nanometers. External magnetic field-enhanced photothermal therapy with multi-model imaging was accomplished using FeCUPs. Moreover, no cancer recurrence was found during 14 days of recovery without PTT. Conclusions: Hollow carbon spheres, photothermal agents loaded with upconversion nanoparticles inside and magnetic nanoparticles outside were prepared for photothermal therapy. The aggregation of FeCUPs in tumors by the local magnetic field was verified by MRI and UCL imaging, and PTT was enhanced.

Tailoring Iron Oxide Nanoparticles for Efficient Cellular Internalization and Endosomal Escape

“…For instance, the early diagnosis of Alzheimer’s disease has been attempted with the aid of ION/UCNPs (BaYF 5 host matrix with Yb 3+ , Er 3+ ions) conjugated with the Aβ 0 aptamer (DNA1) and the complementary oligonucleotide of the Aβ 0 aptamer (DNA2) [ 333 ]. ION/UCNPs (NaGdF 4 host matrix with Yb 3+ , Er 3+ and Tm 3+ ions) based on hollow carbon spheres have also been employed for tumor elimination and MRI [ 334 ]. Similarly, ION/UCNPs with a Mn 2+ doped NaYF 4 :Yb/Er outer shell showed promising potential for MRI diagnostics [ 335 ].…”

<p>Pathological Mechanism of Photodynamic Therapy and Photothermal Therapy Based on Nanoparticles</p>

“…12 Wang et al proposed that an upconversion Magnetic Agent (FeCUPs) mediated by Hollow carbon spheres provides a dual-function platform of PTT and biological imaging for tumor elimination. 13 The third generation is metal and non-metallic compounds such as CuS and ZnS, which are in the most exciting part of the research. 14,15 It has high photothermal performance and low cost, can be easy to prepared, but it is usually non-fluorescent and lacks the ability of tumortargeted ablation, which limits the rapid real-time fluorescence imaging and localization of primary tumors and lymph node metastases.…”

Energy‐converting biomaterials for cancer therapy: Category, efficiency, and biosafety

“…In addition to Ce‐based scintillating biomaterials, the gadolinium tungstate matrix could serve as an X‐ray antenna and transfer energy to Tb 3+ ions for X‐ray‐induced radio/PDT (Yu et al, 2019). Furthermore, other types of radiation‐driven ROS‐ECBs, such as UCNPs (Fan et al, 2016; Wang et al, 2019; Zhang et al, 2015) and rare earth‐doping nanosystems (Hu et al, 2019; Kotb et al, 2016) have also been explored for enhancing the RT.…”