Reviewed by Lexie CornerNov 6 2024
A recent study conducted by researchers from the Politecnico di Milano, in collaboration with Aalto University, the VTT-Technical Research Centre in Finland, and the SCITEC Institute of the CNR, aimed to develop hydrophobic paper by leveraging the mechanical properties and water resistance of cellulose nanofibers. This research seeks to create a sustainable, high-performance material suitable for packaging and biomedical applications.
Schematic illustration of the hybrid network based on CNF and DFNKF, highlighting the residues exploited for functionalization and interaction with CNF. The halogenated derivatives, DF(I)NKF and DF(F5)NKF, were obtained by substituting the Phe in the second position with the corresponding halogenated amino acids. Credit: Journal of Materials Chemistry B (2024).
This approach utilized supramolecular techniques, combining short protein chains (peptide sequences) with cellulose nanofibers without chemically modifying them. Such hydrophobic paper could potentially replace petroleum-based products in the future.
Cellulose nanofibers (CNFs), derived from cellulose—a renewable and biodegradable material—are well-known for their strength and versatility. In this study, researchers from the SupraBioNanoLab at the "Giulio Natta" Department of Chemistry, Materials, and Chemical Engineering at the Politecnico di Milano demonstrated that the properties of cellulose nanofibers could be significantly enhanced through the incorporation of small proteins called peptides, all without chemical modification.
Our supramolecular approach involved adding small sequences of peptides, which bind onto the nanofibers and so improve their mechanical performance and water resistance. The results of the study showed that even minimal quantities of peptides (less than 0.1 %) can significantly increase the mechanical properties of the hybrid materials produced, giving them greater resistance to stress.
Elisa Marelli, Study Co-Author, Politecnico di Milano
The researchers also evaluated the effect of incorporating fluorine atoms into the peptide sequences. This modification allowed the creation of a structured hydrophobic film on the material, enhancing its water resistance while maintaining its biocompatibility and sustainability.
This advance opens up new opportunities for creating biomaterials that can compete with petroleum-derived materials in terms of performance, achieving the same quality and efficiency while reducing environmental impact. These hybrid materials are very suitable for sustainable packaging, where resistance to moisture is vital, and also for use in biomedical devices, thanks to their biocompatibility.
Pierangelo Metrangolo, Study Co-Author, Politecnico di Milano
Journal Reference:
Marchetti, A., et al. (2024) Nanocellulose-Short Peptide Self-Assembly for Improved Mechanical Strength and Barrier Performance. Journal of Materials Chemistry B. doi.org/10.1039/d4tb01359j.