New antibacterial films are designed with the capability to reversibly regulate their killing and repelling functions in response to variations in environmental pH. These systems consist of porous polystyrene surfaces as the main components and a copolymer bearing pH-sensitive thiazole and triazole groups as the minor components. These pH-sensitive groups, located on the surfaces, can be partially protonated at acidic pH levels, increasing the positive charge density of the surfaces and their antibacterial activity. Similarly, their bacterial adhesion and killing efficiencies in response to changes in pH are evaluated by analyzing the bacterial viability of Staphylococcus aureus bacteria on the surfaces under acidic and neutral pH values. It is demonstrated that after only 1 h of incubation with the bacterial suspension in acidic conditions, the surfaces killed the bacteria, while at pH = 7.4, some of the adhered bacteria are removed. Furthermore, the surface topography exerts an important role by intensifying this response.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/mabi.201900127 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Polymer Ligands with Multi-Nitrogen Heterocyclic Carbenes for Enhanced Stability and Reactivity in Nanoparticle Surface Functionalization.
Angew Chem Int Ed Engl
January 2025
Fudan University, Department of Macromolecular Science, 2205 Songhu Rd, 200438, Shanghai, CHINA.
Nitrogen heterocyclic carbenes (NHCs) are emerging as effective substitutes for conventional thiol ligands in surface functionalization of nanoparticles (NPs), offering exceptional stability to NPs under harsh conditions. However, the highly reactive feature of NHCs limits their use in introducing chemically active groups onto the NP surface. Herein, we develop a general yet robust strategy for the efficient surface functionalization of NPs with copolymer ligands bearing various functional groups.
View Article and Find Full Text PDFQuantum Chemical NMR Spectroscopic Structural Analysis in Solution: The Investigation of 3-Indoleacetic Acid Dimer Formation in Chloroform and DMSO Solution.
Magn Reson Chem
January 2025
Laboratório de Química Computacional e Modelagem Molecular (LQC-MM), Departamento de Química Inorgânica, Instituto de Química, Universidade Federal Fluminense (UFF), Niterói, Rio de Janeiro, Brazil.
We present a DFT-PCM NMR study of 3-indoleacetic acid (3-IAA), used as a working example, including explicit solvent molecules, named PCM-nCHCl, PCM-nDMSO (n = 0, 2, 4, 8, 14, 20, and 25), to investigate the dimer formation in solution. Apart from well-known cyclic (I) and open (II) acetic acid (AA) dimers, two new structures were located on DFT-PCM potential energy surface (PES) for 3-IAA named quasicyclic A (III) and quasicyclic B (IV), the last one having N-H…O hydrogen bond (instead of O-H…O). In addition, four other structures having π-π type interactions named V, VI, VII, and VIII were also obtained completing the sample on the PES.
View Article and Find Full Text PDFComputational Insights Into Corrosion Inhibition Mechanism: Dissociation of Imidazole on Iron Surface.
J Comput Chem
January 2025
Department of Chemistry, National University of Singapore, Singapore.
Corrosion inhibitors are widely used to mitigate safety risks and economic losses in engineering, yet post-adsorption processes remain underexplored. In this study, we employed density functional theory calculations with a periodic model to investigate the dissociation mechanisms of imidazole on the Fe(100) surface. Imidazole was found to adsorb optimally in a parallel orientation, with an adsorption energy of -0.
View Article and Find Full Text PDFCryo-EM SPR structures of Salmonella typhimurium ArnC; the key enzyme in lipid-A modification conferring polymyxin resistance.
Protein Sci
February 2025
Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada.
Polymyxins are last-resort antimicrobial peptides administered clinically against multi-drug resistant bacteria, specifically in the case of Gram-negative species. However, an increasing number of these pathogens employ a defense strategy that involves a relay of enzymes encoded by the pmrE (ugd) loci and the arnBCDTEF operon. The pathway modifies the lipid-A component of the outer membrane (OM) lipopolysaccharide (LPS) by adding a 4-amino-4-deoxy-l-arabinose (L-Ara4N) headgroup, which renders polymyxins ineffective.
View Article and Find Full Text PDFUltrasound-Based Local Lung Motion Assessment Using Synthetic Lateral Phase.
J Clin Ultrasound
January 2025
JD Hamilton Consulting, Brighton, Michigan, USA.
Background: Ultrasound lung surface motion measurement is valuable for the evaluation of a variety of diseases. Speckle tracking or Doppler-based techniques are limited by the loss of visualization as a tracked point moves under ribs or is dependent.
Methods: We developed a synthetic lateral phase-based algorithm for tracking lung motion to overcome these limitations.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!