Work

Silver–Histidine-Immobilized Laponite Nanoclays as Antibacterial Agents in Food Coatings for Controlling Bacterial Contamination on Green Grapes

Year: 2026

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide In this study, silver–histidine-immobilized Laponite nanodisks are developed for use as alternative antibacterial agents for food contact materials. The silver–histidine complex [Ag(HHis)] + is immobilized onto Laponite RD nanoparticles through an ion-exchange reaction. The resulting silver–histidine-immobilized Laponite nanodisks ([Ag(HHis)] + LP) are characterized by inductively coupled plasma optical emission spectroscopy, X-ray diffraction, transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy, dynamic light scattering, and zeta potential analysis to confirm the successful immobilization of the [Ag(HHis)] + complex onto the Laponite surfaces. The transparent antibacterial food coatings based on [Ag(HHis)] + LP nanodisks and cellulose nanofibers (CNF) are subsequently developed. The antibacterial activities of the [Ag(HHis)] + LP dispersion, the [Ag(HHis)] + LP-CNF dispersion, and the [Ag(HHis)] + LP-CNF nanocomposite films are evaluated against E. coli and S. aureus using minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays, Modify BSEN 1276:2019 method, and the JIS Z 2801:2010 method, respectively. The [Ag(HHis)] + LP-CNF nanocomposite films exhibit favorable mechanical, optical, and barrier properties, and the nanocomposite coatings can be applied to green grape berries as a model fruit without altering their genuine physical appearance. Furthermore, the migration test of the coated green grape berries reveals that residual silver ions detected in the grape pulp are below the ICP-OES detection limit of 0.0076 ppm, and the coatings are fully removable with water. Notably, the optimal [Ag(HHis)] + LP-CNF nanocomposite coating, formulated with an initial Ag + concentration of 100 ppm, can effectively suppress bacterial contamination and extend the shelf life of green grape berries up to 21 days.

Source: ACS Omega

DOI: 10.1021/acsomega.6c00622

Authors: Sutthida Sukaiem, Nutthaphol Khupsathianwong, Chanikan Sonklin, Tewarak Parnklang

Institution: King Mongkut's University of Technology North Bangkok

Language: English

Topic: Nanocomposite Films for Food Packaging

Subfield: Biomaterials

Field: Materials Science

Domain: Physical Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $1,935