Hunt for sustainable packaging continues
By Polytechnic University of Milan
Researchers aimed to develop hydrophobic paper by leveraging
the strength and water resistance of cellulose nanofibers, creating a
sustainable, high-performance material suitable for packaging and biomedical
applications. 
SciTechDaily.com
This innovative approach involved integrating short protein
chains, known as peptide sequences, without chemically altering the cellulose
nanofibers. The result is a potential alternative to petroleum-based materials,
with significant environmental benefits.
The study, titled “Nanocellulose-short peptide self-assembly
for improved mechanical strength and barrier performance,” was recently
featured on the cover of the Journal of Materials Chemistry B. The
research was conducted by the “Giulio Natta” Department of Chemistry,
Materials, and Chemical Engineering at Politecnico di Milano, in collaboration
with Aalto University, the VTT-Technical Research Centre of Finland, and the
SCITEC Institute of the CNR.
Enhancing Cellulose with Peptides
Cellulose nanofibers (CNFs) are natural fibers derived from
cellulose — a renewable and biodegradable source — and are well known for their
strength and versatility. In the study, the researchers from the
SupraBioNanoLab of the “Giulio Natta” Department of the Politecnico di Milano
showed how it is possible to greatly improve the properties of cellulose
nanofibers without chemically modifying them, instead adding small proteins
known as peptides.
“Our supramolecular approach involved adding small sequences
of peptides, which bind onto the nanofibers and so improve their mechanical
performance and water-resistance. Elisa Marelli, co-author of the study,
explained the methodology: “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.”
Breakthroughs in Biocompatible Materials
Finally, the researchers assessed the impact of adding
fluorine atoms in the peptide sequences. This made it possible to create a
structured hydrophobic film on the material, providing even greater water
resistance while still preserving its biocompatible and sustainable
characteristics.
As Pierangelo Metrangolo, co-author of the study, pointed
out: “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.”
Reference: “Nanocellulose-short peptide self-assembly for
improved mechanical strength and barrier performance” by Alessandro Marchetti,
Elisa Marelli, Greta Bergamaschi, Panu Lahtinen, Arja Paananen, Markus Linder,
Claudia Pigliacelli and Pierangelo Metrangolo, 19 August 2024, Journal
of Materials Chemistry B.
DOI:
10.1039/D4TB01359J
