Polydiacetylene as a Biosensor: Fundamentals and Applications in the Food Industry

Biosensors offer the potential for real-time pathogen detection. Polydiacetylene (PDA) is an ideal choice for use as a sensor due to its unique optical properties. PDA molecules can form thin films or vesicles that change color from deep blue to red in response to different stimuli, like temperature, pH, and the presence of biological molecules. PDA films and vesicles have been proven to be promising devices for the detection of bacteria and bacterial toxins. Langmuir troughs (for films) and microcalorimetry (for vesicles) are among the many techniques used to characterize PDA films and vesicles. In order to enable more applications of PDA films, it is imperative to elucidate and gain a deeper understanding of the molecular interactions associated with their color change. In addition, it is necessary to transfer the PDA film onto a solid support like plastic in order to incorporate PDA biosensors into an intelligent packaging system. Through the use of such a system, consumers can monitor food quality, thereby preventing foodborne outbreaks. In this review, we discuss the formation of PDA films and vesicles, their characteristics, and their potential applications as biosensors. The possibility to incorporate PDA biosensors into an intelligent packaging system to be used in the food industry is also explored.