Development and characterization of starch/PVA antimicrobial active films with controlled release property by utilizing electrostatic interactions between nanocellulose and lauroyl arginate ethyl ester.

The two nanocellulose (nanofibrillated cellulose (NFC) and carboxylated nanofibrillated cellulose (C-NFC)) could interact with lauryl arginine ethyl ester hydrochloride (LAE) through electrostatic bonding. The zeta potential (absolute value) of C-NFC (-27.80 mV) was higher than that of NFC (-10.07 mV). The starch/polyvinyl alcohol active films with controlled release property by utilizing electrostatic interactions between nanocellulose and LAE were prepared and their properties were investigated. For incorporation of the NFC or C-NFC, the cross-section of the films became slightly uneven and some fibrils were observed, the films exhibited an increase in strength, while the film water vapor and oxygen barrier properties decreased. The release of LAE from the films to food simulants (10 % ethanol) decelerated with increasing of NFC or C-NFC. These might be mainly attributed to the enhanced electrostatic interaction between NFC or C-NFC and LAE. It demonstrated that nanocellulose with higher negative charges would exhibit stronger electrostatic interaction with LAE, thus slowing the release of LAE. The film with highest C-NFC content exhibited smallest inhibition zone among LAE-containing films, which was related with its slowest release rate of LAE. It showed a great prospect to develop controlled release active packaging films by utilizing electrostatic interactions between substances.