Bacteria-targeted photothermal therapy for combating drug-resistant bacterial infections

Chitosan-modified molybdenum selenide mediated efficient killing of Helicobacter pylori and treatment of gastric cancer

Helicobacter pylori (H. pylori) is one of the major causes of gastrointestinal diseases, including gastric cancer. However, the acidic environment of the stomach and H. pylori resistance severely impair the antimicrobial efficacy of oral drugs. Here, a biocompatible chitosan-modified molybdenum selenide (MoSe2@CS) was designed for the simultaneous photothermal treatment of H. pylori infection and gastric cancer. MoSe2@CS showed a photothermal conversion efficiency was as high as 45.7 %. In the H. pylori-infected mice model, MoSe2@CS displayed a high bacteriostasis ratio of 99.9 % upon near-infrared irradiation. The antimicrobial functionality was also proved by transcriptomic sequencing study, which showed that MoSe2@CS combined with NIR laser irradiation modulated the gene expression of a variety of H. pylori bioprocesses, including cell proliferation and inflammation-related pathways. Further gut flora analysis results indicated that MoSe2@CS mediated PTT of H. pylori did not affect the homeostasis of gut flora, which highlights its advantages over traditional antibiotic therapy. In addition, MoSe2@CS exhibited a good photothermal ablation effect and significantly inhibited gastric tumor growth in vitro and in vivo. The comprehensive application of MoSe2@CS in the PTT of H. pylori infection and gastric cancer provides a new avenue for the clinical treatment of H. pylori infection and related diseases.

Research Progress on Ti3C2Tx-Based Composite Materials in Antibacterial Field

The integration of two-dimensional Ti3C2Tx nanosheets and other materials offers broader application options in the antibacterial field. Ti3C2Tx-based composites demonstrate synergistic physical, chemical, and photodynamic antibacterial activity. In this review, we aim to explore the potential of Ti3C2Tx-based composites in the fabrication of an antibiotic-free antibacterial agent with a focus on their systematic classification, manufacturing technology, and application potential. We investigate various components of Ti3C2Tx-based composites, such as metals, metal oxides, metal sulfides, organic frameworks, photosensitizers, etc. We also summarize the fabrication techniques used for preparing Ti3C2Tx-based composites, including solution mixing, chemical synthesis, layer-by-layer self-assembly, electrostatic assembly, and three-dimensional (3D) printing. The most recent developments in antibacterial application are also thoroughly discussed, with special attention to the medical, water treatment, food preservation, flexible textile, and industrial sectors. Ultimately, the future directions and opportunities are delineated, underscoring the focus of further research, such as elucidating microscopic mechanisms, achieving a balance between biocompatibility and antibacterial efficiency, and investigating effective, eco-friendly synthesis techniques combined with intelligent technology. A survey of the literature provides a comprehensive overview of the state-of-the-art developments in Ti3C2Tx-based composites and their potential applications in various fields. This comprehensive review covers the variety, preparation methods, and applications of Ti3C2Tx-based composites, drawing upon a total of 171 English-language references. Notably, 155 of these references are from the past five years, indicating significant recent progress and interest in this research area.

Nanotechnology-driven strategies to enhance the treatment of drug-resistant bacterial infections

The misuse of antibiotics has led to increased bacterial resistance, posing a global public health crisis and seriously endangering lives. Currently, antibiotic therapy remains the most common approach for treating bacterial infections, but its effectiveness against multidrug-resistant bacteria is diminishing due to the slow development of new antibiotics and the increase of bacterial drug resistance. Consequently, developing new a\ntimicrobial strategies and improving antibiotic efficacy to combat bacterial infection has become an urgent priority. The emergence of nanotechnology has revolutionized the traditional antibiotic treatment, presenting new opportunities for refractory bacterial infection. Here we comprehensively review the research progress in nanotechnology-based antimicrobial drug delivery and highlight diverse platforms designed to target different bacterial resistance mechanisms. We also outline the use of nanotechnology in combining antibiotic therapy with other therapeutic modalities to enhance the therapeutic effectiveness of drug-resistant bacterial infections. These innovative therapeutic strategies have the potential to enhance bacterial susceptibility and overcome bacterial resistance. Finally, the challenges and prospects for the application of nanomaterial-based antimicrobial strategies in combating bacterial resistance are discussed. This article is categorized under: Biology-Inspired Nanomaterials > Nucleic Acid-Based Structures Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease.

Nanogold-coated stent facilitated non-invasive photothermal ablation of stent thrombosis and restoration of blood flow

In-stent restenosis (ISR) and stent thrombosis (ST) are the most serious complications of coronary angioplasty and stenting. Although the evolution of drug-eluting stents (DES) has significantly restricted the incidence of ISR, they are associated with an enhanced risk of ST. In the present study, we explore the photothermal ablation of a thrombus using a nano-enhanced thermogenic stent (NETS) as a modality for revascularization following ST. The photothermal activity of NETS, fabricated by coating bare metal stents with gold nanorods generating a thin plasmonic film of gold, was found to be effective in rarefying clots formed within the stent lumen in various in vitro assays including those under conditions mimicking blood flow. NETS implanted in the rat common carotid artery generated heat following exposure to a NIR-laser that led to effective restoration of blood flow within the occluded vessel in a model of ferric chloride-induced thrombosis. Our results present a proof-of-concept for a novel photothermal ablation approach by employing coated stents in the non-invasive management of ST.

Novel Antibacterial Materials and Coatings-A Perspective by the Editors

The fight between humans and bacteria has escalated to a new level.