Nitric oxide integrated polyethylenimine-based tri-block copolymer for efficient antibacterial activity

Area of Science:

• Biomaterials Science
• Antimicrobial Research
• Polymer Chemistry

Background:

• Antibiotic resistance necessitates novel antimicrobial strategies.
• Nitric oxide (NO) possesses potent antimicrobial properties.
• Developing biocompatible NO-releasing materials is crucial for therapeutic applications.

Purpose of the Study:

• To synthesize and characterize a novel nitric oxide (NO)-releasing polymeric material.
• To evaluate the in vitro antibacterial efficacy of the synthesized material against Gram-negative and Gram-positive bacteria, including resistant strains.
• To assess the biocompatibility and mechanism of bacterial membrane disruption.

Main Methods:

• Synthesis of a thermosensitive polymer (Pluronic F68) functionalized with branched polyethylenimine (BPEI) and N-diazeniumdiolates (NONOates).
• In vitro antibacterial assays using Gram-negative Escherichia coli (E. coli), Gram-positive Staphylococcus aureus (S. aureus), and methicillin-resistant S. aureus (MRSA).
• Confocal microscopy and Transmission Electron Microscopy (TEM) for evaluating antibacterial activity and bacterial membrane integrity.

Main Results:

• Successful synthesis of F68-BPEI-NONOates, a biocompatible NO-releasing polymer.
• Demonstrated significant killing of E. coli, S. aureus, and MRSA under physiological conditions.
• Confocal microscopy confirmed potent antibacterial activity, while TEM revealed bacterial membrane destruction.
• Exhibited low in vitro cytotoxicity, indicating good biocompatibility.

Conclusions:

• F68-BPEI-NONOates is an effective NO-releasing material with broad-spectrum antibacterial activity.
• The material demonstrates a promising strategy for combating drug-resistant bacterial infections.
• Its biocompatibility and efficient bacterial killing mechanism highlight its therapeutic potential.