Confined structure regulations of molybdenum oxides for efficient tumor photothermal therapy

Abstract

Molybdenum oxide nanoparticles (NPs) with tunable plasmonic resonance in the near-infrared region display superior semiconducting features and photothermal properties, which are highly related to the crystalline and defective structures such as oxygen deficiencies. However, fundamental understanding on the structure-function relationship between crystalline/defective structures and photothermal properties is still unclear. To address this, herein, we have developed an "in-situ confined oxidation-reduction" strategy to regulate the defect features of molybdenum oxide NPs in the dual-mesoporous silica nanoreactor. Especially, the effects of crystalline structure/oxygen defects of molybdenum oxides on the photothermal performances were investigated by facilely tuning the amount of molybdenum resource and the reduction temperature. As a photothermal nanoagent, the optimal defective molybdenum oxide NPs encapsulated in PEGylated porous silica nanoreactor (designated as MoO 3−x @PPSNs) exhibit excellent biological stability and strong localized surface plasmon resonance effect in nearinfrared absorption range with the highest photothermal conversion efficiency up to 78.7% under 808 nm laser irradiation. More importantly, the remarkable photothermal effects of MoO 3−x @PPSNs were comprehensively demonstrated both in vitro and in vivo. Consequently, we envision that the plasmonic MoO 3−x NPs in a biocompatible porous silica nanoreactor could be used as an efficient photothermal therapy agent for photothermal ablation of tumors.

Recent Advances and Clinical Potential of Near Infrared Photothermal Conversion Materials for Photothermal Hepatocellular Carcinoma Therapy

“…There are other oxides (including manganese oxide, molybdenum oxide, titanium oxide, and so on) for precise treatment of HCC due to their simple synthesis and excellent photothermal conversion efficiency over and above those we have discussed. [78,79] Paramagnetic iron oxide nanoparticles encapsulated by polydopamine (PDA) exhibit excellent drug-loading properties and high photothermal conversion efficiency, which are often widely served as near-infrared PTAs in PTT. [80] The photothermal conversion efficiency is improved by wrapping the oxide with PDA, on the basis of which the inner oxide is changed, such as Prussian Blue (PB)/MnO 2 , to achieve high-precision temperature control as well as low damage to normal tissues.…”

A single-step plasma method for rapid production of 2D, ferromagnetic, surface vacancy-engineered MoO3−x nanomaterials, for photothermal ablation of cancer

“…Non-stoichiometric MoO 3−x (0 < x 1) with oxygen vacancies may be endowed with some extremely useful properties, like possessing metallic behaviour, having intermediate electronic states within their band gap, efficient localized surface plasmon resonance (LSPR) absorption in the NIR region and induced room-temperature ferromagnetic behavior. Due to their unique NIR light absorption characteristics, MoO 3−x is used in PTT treatment of cancer [1][2][3][4][5][6].…”

Confined Construction of Ultrasmall Molybdenum Disulfide-Loaded Porous Silica Particles for Efficient Tumor Therapy

“…Compared with organic PTAs, inorganic PTAs possess a higher photothermal conversion efficiency (PCE) and better photothermal stability . Till now, various kinds of inorganic PTAs, including noble metal particles, transition metal sulfide materials, metal oxides, and carbon-based nanosystems, , have been reported for effective tumor PTT. However, developing high-performance and biocompatible inorganic PTAs for efficient tumor therapy remains a significant challenge.…”