The carbon quantum dots: Preparation, antibacterial mechanisms, and application in food packaging

In recent years, food spoilage and deterioration caused by microbial contamination have become increasingly serious. Traditional food packaging materials can inhibit the growth and reproduction of microorganisms, thereby extending the shelf life of food. Unfortunately, traditional packaging materials have limitations, including limited antibacterial performance, easy environmental pollution, and poor biocompatibility. Hence, the development of food packaging materials with antibacterial properties has become a research hotspot. Carbon quantum dots (CQDs), as emerging food packaging materials, have excellent antibacterial activity, good biocompatibility, and low toxicity. Therefore, CQDs show broad application prospects in the field of food packaging. This paper initially reviews the preparation methods (arc discharge, laser etching, electrochemical exfoliation, etc.) of CQDs and the selection of carbon sources (carbon-based materials, small molecule organic compounds, and biomass carbon sources). Subsequently, this review systematically summarizes the antibacterial mechanisms of CQDs. Finally, this article comprehensively outlines the application of CQDs in the packaging of fruits and vegetables, meats, seafood, grains, and dairy products. The findings provide theoretical support for the further application of CQDs in the field of food packaging.