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In recent years, photodynamic therapy (PDT) has been frequently applied in the treatment of bacterial infections. However, reactive oxygen species (ROS) produced by PDT have a short lifetime and operating distance, resulting in a generally inadequate therapeutic efficacy. Herein, we report the fabrication of a nanostructure-based PDT amplifier composite coating via self-assembly between MIL-96 (Ga) particles, dopamine (DA), and methylene blue (MB). The coatings exhibited a bacterial inhibition rate of over 99% after 5 min of red light exposure. Based on the chelation between Ga3+ and DA, these metal–organic frameworks (MOFs) can stably adhere to surfaces of various substrates, such as polyurethane (PU), nonwoven, and titanium (Ti) alloy. The Ga-MOF can slowly and consistently release Ga3+, avoiding the rapid hydration of Ga3+. Furthermore, after loading MB, the nanostructure-based Ga-MOF composite coating exhibits PDT capability triggered by red light (660 nm). By blocking of bacterial iron metabolism through Ga3+, the coating disrupts bacterial antioxidant systems and significantly enhances PDT efficacy. In addition, the iron block antibacterial therapy (IBAT)/PDT coating also shows excellent in vitro biocompatibility. This work provides an innovative antibacterial strategy for medical device surfaces. [ABSTRACT FROM AUTHOR]

Antibacterial surfaces that provide synergetic photothermal/photodynamic therapy (PTT/PDT) offer a promising avenue for combating bacterial infections but generally require a time-consuming and cumbersome chemical preparation procedure. Herein, a metal–organic framework (MOF) composite film with PTT/PDT antibacterial performance is realized through a surprisingly fast and sustainable chelation-induced self-assembly between ZIF-8 particles and dopamine (DA). Unlike traditional DA polymerization, usually in an alkaline medium with a long reaction time (e.g. more than 20 h), a robust and universal MOF composite film with DA as the linker can be rapidly assembled within only 0.5 h on various bulk materials under neutral (pH = 7) conditions. The resultant MOF film is extremely robust, and can even withstand harsh ultrasonic cleaning (150 W, 50 kHz, 10 min) and maintain its intact nanostructure. After being incorporated with indocyanine green (ICG), the obtained composite films achieved efficient synergetic PTT/PDT against both Gram-positive and -negative bacteria under single NIR irradiation (808 nm). This PTT/PDT antibacterial film also exhibited excellent in vitro biocompatibility, thus revealing the great potential for medical antibacterial surface applications. [ABSTRACT FROM AUTHOR]

• A coating with anti-adhesive and bactericidal properties was prepared. • Tobramycin works as a bactericidal agent and a cross-linker in polyimide networks. • The coating can be obtained via a facile one-step Schiff-base reaction. Herein, we report an effective bacterial anti-adhesive and bactericidal coating based on a Schiff-base reaction. The hydrophilic polyoxyethylene-bis-amine (PEG-bis-amine) is introduced in the system to endow the coating with valid bacterial anti-adhesive performance, while the tobramycin (Tob) with multi-amines serves as both a bactericidal agent and one of the cross-linkers for the construction of polyimide networks. The coating is obtained via a facile solvent-annealing method. This type of dual-functional antibacterial coating may provide as an excellent antibacterial platform for broad applications in bactericidal surfaces. [ABSTRACT FROM AUTHOR]

Biomaterial-associated infections critically compromise the functionality and performance of the medical devices, and pose a serious threat to human healthcare. Recently, natural DNase enzyme has been recognized as a potent material to prevent bacterial adhesion and biofilm formation. However, the vulnerability of DNase dramatically limits its long-term performance in antibacterial applications. In this work, DNase-mimicking polymer brushes were constructed to mimic the DNA-cleavage activity as well as the macromolecular scaffold of the natural DNase. The bacteria repellent efficacy of DNase-mimicking polymer brush-functionalized surface was comparable to that of the DNase-functionalized surface. More importantly, due to their inherent stability, DNase-mimicking polymer brushes presented the much better performance in inhibiting bacterial biofilm development for prolonged periods of time, as compared to the natural DNase. The as-developed DNase-mimicking polymer brush-functionalized surface presents a promising approach to combat biomaterial-associated infections. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) can function as tumor suppressors and might provide an efficient strategy for annihilating cancer. Specific miRNAs can be reintroduced into tumor cells to elicit the tumor suppressor activities. We show that systemically delivered, synthetic miRNA mimics in complex with a novel neutral lipid emulsion are preferentially targeted to lung tumors and show therapeutic benefit in mouse models of lung cancer. The delivery was demonstrated using mimics of the tumor suppressor microRNA-495 which is found downregulated in most lung cancer. Systemic treatment of a Kras-activated autochthonous mouse model of non-small cell lung cancer (NSCLC) led to a significant decrease in tumor burden. Specifically, mice treated with microRNA-495 displayed a large reduction in tumor area compared to mice treated with a miRNA control. These findings provide direct evidence that systematically delivered synthetic miRNA mimics to the mammalian lung can inhibit tumor proliferation and support the promise of miRNAs as a targeted therapy for lung cancer in future. [ABSTRACT FROM AUTHOR]

• A bactericidal shape memory polyurethanes (SMPU) composite film was prepared. • Biofilm can be detached from the surface of the film upon a thermal stimulation. • The SMPU composite film shows low cell cytotoxicity, without leaching of bactericidal species. Biofilms that are responsible for a variety of chronic infections and antibiotic resistance have drawn much attention worldwide. A new strategy for mechanically disrupting and removing biofilms by thermal-triggered shape memory polyurethanes (SMPU) film composited with zinc oxide nanoparticles (ZnO NPs) is reported here. Upon thermal triggered shape recovery, most of the adhered biofilm can be detached from the surface of the SMPU, while the incorporated ZnO NPs could efficiently eliminate the adhered initially and residual bacteria after detaching activity, without leaching of bactericidal species. Furthermore, the composite films exhibited low cytotoxicity to mammalian cells as revealed by cell viability tests. We envision that this antibacterial strategy may find unique applications in biomedical devices, especially for those biofilm-associated infections. [ABSTRACT FROM AUTHOR]