Development, fabrication, and applications of laser-induced graphene-based biosensors in food and dairy sectors

Laser-induced graphene (LIG) has emerged as a cutting-edge carbon material with a unique porous architecture and superior electrochemical properties. Owing to its promising potential to immobilize various biological analytes, LIG has gained intense interest in the development of next-generation biosensors. Direct laser scribing on natural or polymeric substrate materials produces LIG electrodes with tunable properties, offers controlled microstructures, ease surface modifications, and doping with suitable elements, making it promising for electroanalytical measurements. Furthermore, LIG technology stands out as being cost-effective and supports environmental sustainability and eco-conscious solutions. These diverse features open new frontiers, making it suitable for fundamental applications in diverse fields, particularly in the food and dairy industry, where rapid, on-site, and precise monitoring is vital. This review comprehensively discusses fabrications of LIG-based biosensors with a focus on various laser sources, substrate materials, and surface modifications. The core sensing mechanisms of LIG biosensors are thoroughly summarized which enable high sensitivity and selectivity. However, special attention is given to LIG biosensors' applications in the food and dairy industry for the monitoring of food pathogens, food ingredients, food spoilage, biogenic amines, food additives, antibiotics, chemical contaminants, and pesticides. Finally, this review discusses the current challenges of LIG-based biosensors, such as reproducibility, stability, and integration into commercial industries, while offering a future outlook for potential applications. By highlighting recent advances and summarizing knowledge gaps, this review provides new insights into LIG-based sensors and their applications in the food and dairy industry to ensure food quality and safety.