Fabrication of litchi-like lignin/zinc oxide composites with enhanced antibacterial activity and their application in polyurethane films | JoVE Visualize

Fabrication of litchi-like lignin/zinc oxide composites with enhanced antibacterial activity and their application in polyurethane films

Yuanyuan Wang¹, Huan Wang¹, Zhixian Li²

¹School of Chemistry and Chemical Engineering, Guangdong Provincial Engineering Research Center for Green Fine Chemicals, South China University of Technology, 381 Wushan Road, Tianhe District, Guangzhou 510641, China.

Journal of Colloid and Interface Science|March 27, 2021

View abstract on PubMed

Summary

Quaternized lignin/zinc oxide nanostructured composites (QLS/ZnO NCs) show enhanced antibacterial activity against E. coli and S. aureus. These green materials offer improved performance in polyurethane films, demonstrating potential for various applications.

Area of Science:

Materials Science
Nanotechnology
Biotechnology

Background:

Lignin offers a green and effective approach for modifying zinc oxide (ZnO)-based materials.
Developing novel antibacterial agents is crucial for public health and material preservation.

Purpose of the Study:

To synthesize quaternized lignin/zinc oxide nanostructured hybrid composites (QLS/ZnO NCs).
To evaluate the antibacterial efficacy and mechanisms of QLS/ZnO NCs.
To investigate the performance of QLS/ZnO NCs incorporated into polyurethane films.

Main Methods:

Facile hydrothermal synthesis of QLS/ZnO NCs.
Quaternization of sodium lignosulfonate (LS) to impart positive charges.
Characterization of morphology, particle size, and antibacterial activity.
Determination of minimal inhibition concentrations (MICs) and minimal bactericidal concentrations (MBCs).

Main Results:

QLS/ZnO NCs exhibited a litchi-like morphology with nanorods (5-10 nm diameter) and good dispersion.
QLS/ZnO NCs demonstrated significantly enhanced antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) compared to bare ZnO, achieving sterilization rates of 97.54% and 99.55%, respectively.
Antibacterial activity was attributed to electrostatic interactions, cell membrane damage, and light-activated reactive oxygen species (ROS) production.
MICs were 100 μg/mL for both bacteria, and MBCs were 100 μg/mL (E. coli) and 200 μg/mL (S. aureus).
Polyurethane films incorporating QLS/ZnO NCs showed excellent antibacterial properties, enhanced tensile strength, and improved UV blocking.

Conclusions:

QLS/ZnO NCs represent a highly effective green antibacterial agent due to their unique morphology and surface charge.
The composite materials offer a promising solution for developing advanced antibacterial coatings and films with multiple functionalities.
Further research into optimizing QLS/ZnO NCs for specific applications is warranted.