Continuous preparation of antimony nanocrystals with near infrared photothermal property by pulsed laser ablation in liquids

Application of photothermal effects of nanomaterials in food safety detection

Numerous nanomaterials endowed with outstanding light harvesting and photothermal conversion abilities have been extensively applied in various fields, such as photothermal diagnosis and therapy, trace substance detection, and optical imaging. Although photothermal detection methods have been established utilizing the photothermal effect of nanomaterials in recent years, there is a scarcity of reviews regarding their application in food safety detection. Herein, the recent advancements in the photothermal conversion mechanism, photothermal conversion efficiency calculation, and preparation method of photothermal nanomaterials were reviewed. In particular, the application of photothermal nanomaterials in various food hazard analyses and the newly established photothermal detection methods were comprehensively discussed. Moreover, the development and promising future trends of photothermal nanomaterial-based detection methods were discussed, which provide a reference for researchers to propose more effective, sensitive, and accurate detection methods.

A novel method for ZnO@NiO core-shell nanoparticle synthesis using pulse laser ablation in liquid and plasma jet techniques

Given their versatile nature and wide range of possible applications, core-shell nanoparticles (NPs) have received considerable attention. This paper proposes a novel method for synthesizing ZnO@NiO core-shell nanoparticles using a hybrid technique. The characterization demonstrates the successful formation of ZnO@NiO core-shell nanoparticles, which have an average crystal size of 13.059 nm. The results indicate that the prepared NPs have excellent antibacterial activity against both Gram-negative and Gram-positive bacteria. This behavior is primarily caused by the accumulation of ZnO@NiO NPs on the bacteria's surface, which results in cytotoxic bacteria and a relatively increased ZnO, resulting in cell death. Moreover, the use of a ZnO@NiO core-shell material will prevent the bacteria from nourishing themselves in the culture medium, among many other reasons. Finally, the PLAL is an easily scalable, cost-effective, and environmentally friendly method for the synthesis of NPs, and the prepared core-shell NPs could be used in other biological applications such as drug delivery, cancer treatment, and further biomedical functionalization.

2D antimonene-integrated composite nanomedicine for augmented low-temperature photonic tumor hyperthermia by reversing cell thermoresistance

The overexpression of heat shock proteins (HSPs) in tumor cells can activate inherent defense mechanisms during hyperthermia-based treatments, inducing thermoresistance and thus diminishing the treatment efficacy. Here, we report a distinct "non-inhibitor involvement" strategy to address this issue through engineering a calcium-based nanocatalyst (G/A@CaCO₃-PEG). The constructed nanocatalyst consists of calcium carbonate (CaCO₃)-supported glucose oxidase (GOD) and 2D antimonene quantum dots (AQDs), with further surface modification by lipid bilayers and polyethylene glycol (PEG). The engineered G/A@CaCO₃-PEG nanocatalyst features prolonged blood circulation, which is stable at neutral pH but rapidly degrades under mildly acidic tumor microenvironment, resulting in rapid release of drug cargo in the tumor microenvironment. The integrated GOD effectively catalyzes the depletion of glucose for reducing the supplies of adenosine triphosphate (ATP) and subsequent down-regulation of HSP expression. This effect then augments the therapeutic efficacy of photothermal hyperthermia induced by 2D AQDs upon irradiation with near-infrared light as assisted by reversing the cancer cells' thermoresistance. Consequently, synergistic antineoplastic effects can be achieved via low-temperature photothermal therapy. Systematic in vitro and in vivo evaluations have demonstrated that G/A@CaCO₃-PEG nanocatalysts feature potent antitumor activity with a high tumor-inhibition rate (83.92%). This work thus paves an effective way for augmenting the hyperthermia-based tumor treatments via restriction of the ATP supply.

Antimony Nanopolyhedrons with Tunable Localized Surface Plasmon Resonances for Highly Effective Photoacoustic-Imaging-Guided Synergistic Photothermal/Immunotherapy

Antimony (Sb), a typical group VA semimetal, has rarely been studied both experimentally and theoretically in plasmonic photothermal therapy, possibly due to the lack of effective morphology-controllable methods for the preparation of high-quality Sb nanocrystals. In this study, an effective ligand-guided growth strategy to controllably synthesize Sb nanopolyhedrons (Sb NPHs) with ultrahigh photothermal conversion efficiency (PTCE), good photothermal stability, as well as biocompatibility is presented. Furthermore, the modulation effect of different morphologies on localized surface plasmon resonance (LSPR) of Sb NPHs in experimentation is successfully observed. When the resonance frequency of the Sb NPHs is matched well with the excitation wavelength (808 nm), the PTCE of the Sb NPHs is as high as 62.1%, which is noticeably higher compared to most of the reported photothermal agents. The Sb NPHs also exhibit good photothermal stability. In addition, Sb-NPHs-based multifunctional nanomedicines are further constructed via loading 1-methyl-d-tryptophan on PEGylated Sb NPHs for a highly efficient photoacoustic-imaging-guided synergistic photothermal/immune-therapy of tumors in vivo. This work can stimulate further theoretical and experimental investigations of Sb NPHs and other semimetal nanomaterials regarding their LSPR properties and inspire various potential applications of semimetals in biomedicine and sensors.

Biomedical applications of 2D monoelemental materials formed by group VA and VIA: a concise review

The development of two-dimensional (2D) monoelemental nanomaterials (Xenes) for biomedical applications has generated intensive interest over these years. In this paper, the biomedical applications using Xene-based 2D nanomaterials formed by group VA (e.g., BP, As, Sb, Bi) and VIA (e.g., Se, Te) are elaborated. These 2D Xene-based theranostic nanoplatforms confer some advantages over conventional nanoparticle-based systems, including better photothermal conversion, excellent electrical conductivity, and large surface area. Their versatile and remarkable features allow their implementation for bioimaging and theranostic purposes. This concise review is focused on the current developments in 2D Xenes formed by Group VA and VIA, covering the synthetic methods and various biomedical applications. Lastly, the challenges and future perspectives of 2D Xenes are provided to help us better exploit their excellent performance and use them in practice.