The delivery of drugs to focal sites is a central goal and a key challenge in the development of nanomedicine carriers. This strategy can improve the selectivity and bioavailability of the drug while reducing its toxicity. To ensure the specific release of nitric oxide at the site of a bacterial infection without damaging the surrounding normal tissue, we designed a host-guest molecule containing a host molecule with a target moiety and a nitric oxide donor to release nitric oxide. The boronic acid group in the structure of this nanoparticle interacts strongly and specifically with the surface ofE. coli. In addition, the quaternary amine salt can interact electrostatically with bacteria, indicating a large number of negatively charged cell membranes; altering the molecular structure of the cell membrane; increasing the permeability of the cell membrane; and causing cytoplasmic diffusion and cell lysis, resulting in lethal activity against most bacteria. The synthesised molecules were characterised by1H NMR and mass spectrometry. The strong specific interaction of the boronic acid moiety with the surface ofE. coliand the electrostatic interaction of the quaternary amine salt with the cell membrane were confirmed by antibacterial experiments on molecules with and without the targeting moiety. The targeting group-modified micelles enhanced the antibacterial effect of the micelles very effectively through specific interactions and electrostatic interactions. In addition, in vitro skin wound healing experiments also confirmed the targeting and antimicrobial effect of micelles. These results suggest that the specific release of nitric oxide at the site of bacterial infection is an important guide to further address the emergence of antibiotic-resistant strains of bacteria.Keywords:nitric oxide;targeted antimicrobial;wound healing
Chao Wang,Zuyu He,Yunhao Liu,Chuang Zhou,Jing Jiao,Puwang Li,Dequan Sun,Liyun Lin,Ziming Yang
Halloysite nanotubes (Hal) are naturally occurring tubular clay nanomaterials that have a unique tubular structure and surface modifiability. In order to increase the stability and to achieve controlled release of fertilizers, chitosan (CS) was assembled on the surface of Hal as a valve for preparing Hal@CS and to control the mesoporous surface and lumen ports. Transmission electron microscopy (TEM), X-ray diffraction, Fourier transform infrared, thermogravimetric analysis and nitrogen adsorption isotherm analysis were conducted to confirm the successful grafting of CS onto the surface of the Hal. The cumulative release ratio of urea from the Hal@CS in vitro after 96 h was 34.37% without glutathione (GSH). After introducing GSH the rate of release of urea from the Hal@CS increased. The uptake, translocation, and distribution of the Hal@CS in the epidermal layer and endodermis of root tissue were detected by fluorescence labeling and TEM. We conclude that Hal@CS are a potential controlled-release carrier and delivery system for agricultural fertilizers.
Liver fibrosis (LF) is a leading cause of liver-related mortality worldwide. Although antifibrotic drugs are commonly used in clinical practice, their efficacy remains limited. Excessive reactive oxygen species (ROS) in the fibrotic liver microenvironment play a crucial role in LF progression. Nanozymes, owing to their enzyme-mimicking catalytic activity and antioxidant properties, offer a promising strategy for LF treatment. Vanadium-based nanozymes exhibit ROS-scavenging capabilities and promote fibrosis reversal, while zirconium (Zr)-based metal–organic frameworks (MOFs), such as UiO-66, possess excellent biocompatibility and catalytic activity. However, the therapeutic efficacy of nanozymes is hindered by their intrinsic catalytic limitations. Ultrasound (US), a non-invasive therapeutic modality, has been shown to enhance nanozyme activity and improve treatment outcomes. In this study, we developed a dual-nanozyme composite (UiO-66/V 2 C/L-Arg/pPB, UVLp) with targeted ROS-scavenging and L-arginine (L-Arg) delivery capabilities. Upon ultrasound exposure, UVLp releases L-Arg and nanozymes, facilitating nitric oxide (NO) generation, alleviating oxidative stress, and mitigating liver fibrosis. This work introduces a novel ultrasound-activated nanozyme platform for LF therapy, providing valuable insights for clinical translation.
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