Neutron Activated ¹⁵³Sm Sealed in Carbon Nanocapsules for in Vivo Imaging and Tumor Radiotherapy

Abstract

Radiation therapy along with chemotherapy and surgery remain the main cancer treatments. Radiotherapy can be applied to patients externally (external beam radiotherapy) or internally (brachytherapy and radioisotope therapy). Previously, nanoencapsulation of radioactive crystals within carbon nanotubes, followed by end-closing, resulted in the formation of nanocapsules that allowed ultrasensitive imaging in healthy mice. Herein we report on the preparation of nanocapsules initially sealing “cold” isotopically enriched samarium (152Sm), which can then be activated on demand to their “hot” radioactive form (153Sm) by neutron irradiation. The use of “cold” isotopes avoids the need for radioactive facilities during the preparation of the nanocapsules, reduces radiation exposure to personnel, prevents the generation of nuclear waste, and evades the time constraints imposed by the decay of radionuclides. A very high specific radioactivity is achieved by neutron irradiation (up to 11.37 GBq/mg), making the “hot” nanocapsules useful not only for in vivo imaging but also therapeutically effective against lung cancer metastases after intravenous injection. The high in vivo stability of the radioactive payload, selective toxicity to cancerous tissues, and the elegant preparation method offer a paradigm for application of nanomaterials in radiotherapy.

Nanotechnologies for enhancing cancer immunotherapy

“…H22 and UM-SCC-7 tumor-bearing mice model [40] Remodel TME DOX-AuNPs-GNPs with Losartan 4T1 subcutaneous tumor model [41] Radio-therapy Radiosensitizer Zr-MOF-QU+RT (inhibit CA IX) A549 tumor-bearing BALB/c nude mice [42] Imaging Closed-ended 152 Sm-filled carbon nanocapsules B16F10-Luc tumor-bearing C57BL/6 mice [43] Gene therapy DNA DNA-Au@MNPs A549 subcutaneous tumor model [44] miRNA PCX/(anti-miR-210+siKRAS G12D ) nanoparticles KPC8060 orthotopic pancreatic tumor model [45] siRNA pMSNC/DOX/(T-type Ca 2+ channel) siRNA Orthotopic MCF-7/ADR tumor-xenografted mice model [46] Immuno-therapy Vaccines DC-All-in-one polymersomal nanoformulation (CCPS/HPPH/DOX) MC38 tumor-bearing mice model [47] Peptide-Peptide/pPAA nanoplexes B16 melanoma-bearing mice model [48] Nucleic acid-Au-SGSH-pCMV-MART1 nanoplex B16 melanoma-bearing mice model [49] RNA hurt human body to different degrees. The emergence of characteristic nanoparticle (NP) platforms combined with drugs or markers bring hopes to cancer treatment, imaging, and diagnostic methods [9].…”

“…Nitrosylated maytansinoid DM1-NO poly(lactide-co-glycolic)-block-poly (ethylene glycol) (PLGA-b-PEG) nanoparticles synergistically enhanced RT effect via the inhibition of microtubule polymerization and enrichment of cells at the G2/M phase [94]. Improving imaging capability is the third way, taking isotopesealed nanocapsules which are switchable from "cold" to "hot" under neutron radiation as an example [43]. Multifunctional polymer nanoparticles that designed for heat generation in hyperthermia are more precise diagnostic tools complemented for traditional imaging and diagnostic abilities [95].…”

A Review of the Current State of Nanomedicines for Targeting and Treatment of Cancers: Achievements and Future Challenges

“…A number of studies have reported a wide distribution of various types of nanoparticles following IV administration, including the tumor tissue, liver, and spleen, whereas the amount of NMs is less in other tissues. [ 47,49–53 ] The majority of studies show less accumulation of nanoparticles in the xenograft tumor tissues than other organs, particularly the liver and spleen, following IV administration. An exception is a study by Zhang et al.…”

Nanobiosensor Reports on CDK1 Kinase Activity in Tumor Xenografts in Mice

“…[ 26 ] In particular, thanks to their high specific surface area, they constitute functionalizable platforms, scaffolds of choice for immobilization, or covalent conjugation of a wide variety of bioactive molecules including peptides, antibodies, and protein receptors. [ 27–30 ] CNTs have shown a remarkable capacity to be internalized in cells through crossing the cell membranes within minutes by direct translocation into the cytoplasm or via an energy‐dependent mechanism, such as endocytosis. [ 31 ] In addition, precise control of their surface chemistry enables engineering of multimodal nanotubes and reduction of their pathogenicity.…”