Efficient voltammetric platform combining a molecularly imprinted polymer and silver-nanoparticle-decorated black phosphorus nanosheets for selective determination of Gatifloxacin

An ultrasensitive and selective voltammetric platform combined a molecularly imprinted poly(pyrrole) membrane with Ag-nanoparticle-functionalized black phosphorus nanosheets (MIP/BPNS-AgNPs) was developed for trace GAT detection. The physicochemical properties of the MIP/BPNS-AgNPs were studied by various spectroscopic and electrochemical techniques. BPNS-AgNPs improved the ambient stability and electrochemical activity of the BPNS and possessed a large surface area for accommodating abundant templates to produce specific imprinted sites. The resulting MIP/BPNS-AgNP-modified glassy carbon electrode (GCE) greatly enhanced voltammetric responses for GAT. The MIP/BPNS-AgNP/GCE exhibited admirable GAT determination performance, with two linear responses (0.001-1 and 1-50 μM), high sensitivity (9.965 and 0.5378 μA μM-1), and a low detection limit of 0.2 nM. In addition, the MIP electrode could selectively detect GAT in complex matrices and retain roust responses for a month. The applicability of MIP/BPNS-AgNP/GCE toward the detection of GAT in pharmaceutical formulations, milk, and human serum was verified with satisfactory results.

Recent progress in gold-derived nanomaterials for tumor theranostics

It is widely acknowledged that gold-based materials are of significant interest in the field of biomedicine. Consequently, considerable efforts have been devoted to identifying gold nanoparticles that exhibit effective performance in tumor diagnosis and treatment. However, the underlying reasons for the enhanced efficacy of these gold-based nanomaterials in cancer therapy and diagnosis remain unclear, primarily due to the lack of an in-depth understanding of the mechanisms involved. Therefore, it is essential to summarize the progress in the field to facilitate the rational design of more efficient nanodevices. In this review, we present recent achievements drawn from the latest research to demonstrate the broad applications of gold-based materials. We begin by illustrating the mechanisms of gold-derived nanoparticles during therapeutic and diagnostic processes, including photothermal therapy, photodynamic therapy, sonodynamic therapy, photoacoustic tomography, fluorescence imaging, and X-ray computed tomography. We then summarize the advancements of gold-based nanomaterials in cancer diagnosis and treatment while also analyzing the factors contributing to their enhanced performance. Finally, we highlight key descriptors for evaluating the efficacy and strategies for designing high-performance nanomaterials. This review aims to pave the way for addressing future challenges and outlines directions for the advancement of gold-based biomedicine.

Current advances in black phosphorus-based antibacterial nanoplatform for infection therpy

Black phosphorus (BP) has attracted much attention due to its excellent physiochemical properties. However, due to its biodegradability and simple antibacterial mechanism, using only BP nanomaterials to combat bacterial infections caused by drug-resistant pathogens remains a significant challenge. In order to improve the antibacterial efficiency and avoid the emergence of drug resistance, BP nanomaterials have been combined with other functional materials to form black phosphorus-based antibacterial nanoplatform (BPANP), which provides unprecedented opportunities for the treatment of drug-resistant infections. This article reviews the performance of BPANP and its multiple antibacterial mechanisms while emphatically introducing its design direction and latest application progress in antibacterial fields. Moreover, this paper additionally summarizes and discusses the current challenges and inadequacies of BPANP that need to be improved in future research. We believe that this review will provide researchers with an up-to-date and multifaceted reference, and provide new ideas for designing effective strategies against drug-resistant bacteria.

Nanomaterials for the treatment of bacterial infection by photothermal/photodynamic synergism

In the past few decades, great progress has been made in the field of nanomaterials against bacterial infection. However, with the widespread emergence of drug-resistant bacteria, people try their best to explore and develop new antibacterial strategies to fight bacteria without obtaining or increasing drug resistance. Recently, multi-mode synergistic therapy has been considered as an effective scheme for the treatment of bacterial infections, especially the combination of photothermal therapy (PTT) and photodynamic therapy (PDT) with controllable, non-invasive, small side effects and broad-spectrum antibacterial characteristics. It can not only improve the efficiency of antibiotics, but also do not promote antibiotic resistance. Therefore, multifunctional nanomaterials which combine the advantages of PTT and PDT are more and more used in the treatment of bacterial infections. However, there is still a lack of a comprehensive review of the synergistic effect of PTT and PDT in anti-infection. This review first focuses on the synthesis of synergistic photothermal/photodynamic nanomaterials and discusses the ways and challenges of photothermal/photodynamic synergism, as well as the future research direction of photothermal/photodynamic synergistic antibacterial nanomaterials.

Polydopamine-functionalized selenium nanoparticles as an efficient photoresponsive antibacterial platform

A photoresponsive therapeutic antibacterial platform was designed and constructed using polydopamine-functionalized selenium nanoparticles as a carrier loaded with indocyanine green (Se@PDA-ICG). The therapeutic platform was confirmed by characterization and the antibacterial activity of Se@PDA-ICG against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) was investigated. Under 808 nm laser irradiation, the antibacterial rate of Se@PDA-ICG against E. coli and S. aureus was 100% at 125 μg mL-1. Furthermore, in a mouse wound infection model, the wound closure rate of the Se@PDA-ICG photoresponse group was 88.74% compared with 45.8% for the control group after 8 days of treatment, indicating that it could effectively kill bacteria and dramatically accelerate the wound healing process. These results suggested that Se@PDA-ICG could be a promising photo-activated antibacterial candidate material for biomedical applications.

Magnetic Composite Rapidly Treats Staphylococcus aureus-Infected Osteomyelitis through Microwave Strengthened Thermal Effects and Reactive Oxygen Species

It is difficult to effectively treat bacterial osteomyelitis using photothermal therapy or photodynamic therapy due to poor penetration of light. Here, a microwave (MW)-excited magnetic composite of molybdenum disulfide (MoS₂ ) / iron oxide (Fe₃ O₄ ) is reported for the treatment of bacteria-infected osteomyelitis. In in vitro and in vivo experiments, MoS₂ /Fe₃ O₄ is shown to effectively eradicate bacteria-infected mouse tibia osteomyelitis, due to MW thermal enhancement and reactive oxygen species (ROS) (¹ O₂ and ·O₂ ^- ) production under MW radiation. In addition, the mechanism of MW heat generation is proposed by MW network vector analysis. By the density functional theory and finite element method, the ROS generation mechanism is proposed. The synergy or conductive network between dielectric MoS₂ and magnetic Fe₃ O₄ can reach both enhancement of the dielectric and magnetic attenuation capability. In addition, abundant interfaces are generated to enhance the attenuation of electromagnetic waves by MoS₂ and Fe₃ O_4, introducing multiple reflections and interfacial polarization. Therefore, MoS₂ /Fe₃ O₄ has excellent MW absorption ability based on the synergy or conductive network between MoS₂ and magnetic Fe₃ O₄ as well as multiple dielectric reflections and interfacial polarization.

Applications of Antimicrobial Photodynamic Therapy against Bacterial Biofilms

Antimicrobial photodynamic therapy and allied photodynamic antimicrobial chemotherapy have shown remarkable activity against bacterial pathogens in both planktonic and biofilm forms. There has been little or no resistance development against antimicrobial photodynamic therapy. Furthermore, recent developments in therapies that involve antimicrobial photodynamic therapy in combination with photothermal hyperthermia therapy, magnetic hyperthermia therapy, antibiotic chemotherapy and cold atmospheric pressure plasma therapy have shown additive and synergistic enhancement of its efficacy. This paper reviews applications of antimicrobial photodynamic therapy and non-invasive combination therapies often used with it, including sonodynamic therapy and nanozyme enhanced photodynamic therapy. The antimicrobial and antibiofilm mechanisms are discussed. This review proposes that these technologies have a great potential to overcome the bacterial resistance associated with bacterial biofilm formation.