title: Exploiting the nano-sized features of microfibrillated cellulose (MFC) for the development of controlled-release packaging.
abstract: Microfibrillated cellulose (MFC) was used in this study to prepare films containing an active molecule, lysozyme, which is a natural antimicrobial agent. The main goal of this research was to assess the potential for exploiting the nano-sized dimension of cellulose fibrils to slow the release of the antimicrobial molecule, thus avoiding a too-quick release into the surrounding medium, which is a major disadvantage of most release systems. For this purpose, the release kinetics of lysozyme over a 10-day period in two different media (pure water and water/ethanol 10wt.%) were obtained, and the experimental data was fitted with a solution of Fick's second law to quantify the apparent diffusion coefficient (D). The results indicate that the MFC retained lysozyme, presumably due to electrostatic, hydrogen, and ion-dipole interactions, with the largest release of lysozyme-approximately 14%-occurring from the initial amount loaded on the films. As expected, ethanol as a co-solvent slightly decreased the diffusion of lysozyme from the MFC polymer network. The addition of two potential modulating release agents-glycerol and sodium chloride-was also evaluated. Findings from this work suggest that MFC-based films can be considered a suitable candidate for use in controlled-release packaging systems.
authors.affiliation: STAA, Department of Agriculture-University of Sassari, Viale Italia 39/A, 07100 Sassari, Italy.
authors.forename: Carlo A
authors.initials: CA
authors.lastname: Cozzolino
authors.forename: Fritjof
authors.initials: F
authors.lastname: Nilsson
authors.forename: Marco
authors.initials: M
authors.lastname: Iotti
authors.forename: Benedetta
authors.initials: B
authors.lastname: Sacchi
authors.forename: Antonio
authors.initials: A
authors.lastname: Piga
authors.forename: Stefano
authors.initials: S
authors.lastname: Farris
mesh_terms: D002482:Cellulose / Q000737:chemistry* / Q000378:metabolism; D004058:Diffusion; D005990:Glycerol / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D009113:Muramidase / Q000737:chemistry* / Q000378:metabolism; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D012965:Sodium Chloride / Q000737:chemistry*; D013499:Surface Properties; D013997:Time Factors
chemical_list: D012965:Sodium Chloride; D002482:Cellulose; D009113:Muramidase; D005990:Glycerol