Fe₃O₄@Au@Cu_2−xS Heterostructures Designed for Tri‐Modal Therapy: Photo‐ Magnetic Hyperthermia and ⁶⁴Cu Radio‐Insertion

Abstract

Here, the synthesis and proof of exploitation of three‐material inorganic heterostructures made of iron oxide‐gold‐copper sulfide (Fe3O4@Au@Cu2−xS) are reported. Starting with Fe3O4‐Au dumbbell heterostructure as seeds, a third Cu2−xS domain is selectively grown on the Au domain. The as‐synthesized trimers are transferred to water by a two‐step ligand exchange procedure exploiting thiol‐polyethylene glycol to coordinate Au and Cu2−xS surfaces and polycatechol–polyethylene glycol to bind the Fe3O4 surface. The saline stable trimers possess multi‐functional properties: the Fe3O4 domain, of appropriate size and crystallinity, guarantees optimal heating losses in magnetic hyperthermia (MHT) under magnetic field conditions of clinical use. These trimers have indeed record values of specific adsorption rate among the inorganic‐heterostructures so far reported. The presence of Au and Cu2−xS domains ensures a large adsorption which falls in the first near‐infrared (NIR) biological window and is here exploited, under laser excitation at 808 nm, to produce photo‐thermal heat alone or in combination with MHT obtained from the Fe3O4 domain. Finally, an intercalation protocol with radioactive 64Cu ions is developed on the Cu2−xS domain, reaching high radiochemical yield and specific activity making the Fe3O4@Au@Cu2−xS trimers suitable as carriers for 64Cu in internal radiotherapy (iRT) and traceable by positron emission tomography (PET).

Magnetite‐based Janus nanoparticles, their synthesis and biomedical applications

“…(c) Thermal images acquired by the IR camera (d) Viability of CT‐26 cells incubated with Fe(16)@Au under MHT, PTT, and DUAL (MHT + PTT) (Espinosa et al, 2020). (e) Comparative heating curves obtained for Fe 3 O 4 @Au@Cu 2− x S trimers by application of alternating magnetic field (black curve) only, 808 nm laser irradiation alone (red line), and dual heating at same laser and same magnetic field parameters (blue line) (Fiorito et al, 2022). (f) Tumor photographs and Tumor growth curves of In vivo combined protein/magnetic hyperthermia therapies of Janus MMSNPs@RNaseA (Zuo et al, 2022).…”

“…Recent research has studied the combination of RT and other approaches in various investigations (Beik et al, 2021). For the first time, Fiorito et al (2022) proposed a kind of Janus heterostructure of Fe 3 O 4 @Au@Cu 2− x S as dual‐heating agents in MHT and PTT in combination with RT. In this inorganic trimer, Fe 3 O 4 NPs are suitable for MHT.…”

Rich Landscape of Colloidal Semiconductor–Metal Hybrid Nanostructures: Synthesis, Synergetic Characteristics, and Emerging Applications

“…High image contrast at the tumor sites could be observed after Au–Cu 2– x S or AuPt–CuS HNP injection, significantly larger than that of iopromide or iohexol (Figure B). ,, The hybrids of Au–Cu 2– x S and Au–Cu 2– x Se were investigated also as contrast agents for photoacoustic (PA) imaging (Figure C). ,, In another work, such HNPs were further combined with magnetic Fe 3 O 4 to form Fe 3 O 4 –Au–Cu 2– x S trimers for dual-heating agents based on photothermal and magnetic hyperthermia actuation. An intercalation protocol with radioactive 64 Cu ions on the Cu 2– x S domain reached high radiochemical yield and specific activity, making these HNP trimers suitable as carriers for 64 Cu in internal radiotherapy and traceable by positron emission tomography …”

Threatening sarcoma with combinational therapies: Magnetic hyperthermia using nanoparticles

“…A super magnetic MnFe 2 O 4 nanoparticle coated with a thermosensitive co-polymer loaded with doxorubicin was studied by Shah et al In their study, it was shown that doxorubicin was released at temperatures above the lower critical solution temperature as a result of magnetic hyperthermia, which enhances the cytotoxicity effects at higher temperatures. [109,110] The invention of core-shell structures dates back to the 1980s when heterogeneous and semiconductor materials were discovered. Utilizing a core-shell platform in cancer therapy offers numerous advantages compared to other applicable platforms for multimodal cancer therapy.…”