Synthesis of p-methoxybenzaldehyde/β-cyclodextrin inclusion complex and studies of its release properties in polylactic acid film

Nowadays, due to the rapid development of the times, the study of green controlled release active packaging film has become an integral part of food packaging industry. In order to prepare eco-friendly food green packaging with sustainable release of active ingredients, this study used saturated aqueous solution method to prepare p-methoxybenzaldehyde/β-cyclodextrin inclusion complex, and analyzed the effects of three single factors, namely inclusion temperature, mixing time and inclusion ratio, on the entrapment efficiency and loading capacity. It is found that when the inclusion temperature was 50 °C, mixing time was 4 h and inclusion ratio was 10:1, the entrapment efficiency was 75.18%, the loading capacity could reach 7.52%. Meanwhile, the molecular docking method was used to study molecular interactions, indicating that p-methoxybenzaldehyde can form stable inclusion complexes with β-cyclodextrin. Polylactic acid (PLA) was then used as the base fluid to prepare a p-methoxybenzaldehyde releasable film, which was protected by β-cyclodextrin resulting in a significantly lower release rate than that of added p-methoxybenzaldehyde directly to the film. The inclusion complex was only physical mixing and did not react with PLA, and the inclusion of β-cyclodextrin allowed for effective control of the continuous release of p-methoxybenzaldehyde from the film.

Graphical abstract