Tag Archives: Panu Lahtinen

Cellulose nanofibers for sustainable hydrophobic paper

A November 5, 2024 news item on phys.org announces research with cellulose nanofibers (CNFx)

A recent study has aimed to create hydrophobic paper by exploiting the mechanical properties and water resistance of cellulose nanofibers, and so produce a sustainable, high-performance material suitable for packaging and biomedical devices. This involved a supramolecular approach, i.e., combining short chains of proteins (peptide sequences) that do not chemically modify the cellulose nanofibers. Sustainable hydrophobic paper may one day replace petroleum-related products.

An August 11, 2024 Politecnico di Milano (Polytechnic University of Milan) press release, also on EurekAlert but published November 5, 2024), which originated the news item, provides more information, Note: Links have been removed,

The aim was to create hydrophobic paper by exploiting the mechanical properties and water resistance of cellulose nanofibres, and so produce a sustainable, high-performance material suitable for packaging and biomedical devices. This involved a supramolecular approach, i.e. combining short chains of proteins (peptide sequences) that do not chemically modify the cellulose nanofibres. Sustainable hydrophobic paper may one day replace petroleum-related products.

The study is entitled: Nanocellulose-short peptide self-assembly for improved mechanical strength and barrier performance, and has just featured on the cover of the Journal of Materials Chemistry B. The work was carried out by researchers from the “Giulio Natta” Department of Chemistry, Materials and Chemical Engineering at the Politecnico di Milano, in collaboration with Aalto University, the VTT-Technical Research Centre in Finland and the SCITEC Institute of the CNR.

Cellulose nanofibres (CNFs) are natural fibres 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 (https://www.suprabionano.eu/) of the “Giulio Natta” Department of the Politecnico di Milano showed how it is possible to greatly improve the properties of cellulose nanofibres without chemically modifying them, instead adding small proteins known as peptides.

Our supramolecular approach involved adding small sequences of peptides, which bind onto the nanofibres 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.”

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.

Here’s a link to and a citation for the paper,

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.. J. Mater. Chem. B, 2024,12, 9229-9237 DOI: 10.1039/D4TB01359J First published online: 19 Aug 2024

This paper is open access.

Skin sprays and dressings based on berry extracts and nanocellulose can prevent microbes

There’s an August 27, 2024 news item on Nanowerk that offers intriguing information about an application for nancellulose,

VTT [VTT Technical Research Centre of Finland] has developed a skin spray, based on nanocellulose and antimicrobial compounds from wild berries, which can be used to treat wounds and eliminate hospital-acquired bacteria such as MRSA [methicillin-resistant Staphylococcus aureus] before surgery. The product can also be applied as a cream, transdermal patch or wound dressing.

“The fast-acting surgical spray and efficacious dressing are based on a manufacturing process we have developed, where the surface and pores of a nanocellulose film are impregnated with a berry extract so that the antimicrobial compounds do not get trapped inside the fibre network. VTT has more than 15 years of experience in the laboratory-scale and pilot-scale manufacturing of nanocellulose gels and films”, says Panu Lahtinen, a Senior Scientist at VTT.

An August 27, 2024 VTT press release, which originated the news item, provides more detail about their nanocellulose/berry extract spray and what amounts to a business announcement,

The next step for the berry extract, which is produced using VTT InnoBerry Technologies™ manufacturing method, is to find companies interested in developing, producing and commercialising the products, so they can be launched onto the market in the next few years.
 

In nature, berry compounds protect the seed

The surface of berry seeds is rich in antimicrobial compounds, so berry extracts are useful for food, cosmetic and medical applications. The role of these compounds in nature is to protect the seed from microbes such as moulds before germination, but they can also help prevent the growth of dangerous microbes on human skin. Even a tiny amount of berry extract can kill pathogenic bacteria such as MRSA without harming the skin’s beneficial microbiota.

Berries are used to make juice, but significant quantities of press cake remain as a by-product after processing. This press cake contains the berry skin and seeds, which are rich in antimicrobial compounds. VTT has developed technologies to generate press-cake extracts enriched with these compounds, or to produce the key molecules in cultivated plant cells using plant biotechnology, which allows year-round production unaffected by variations in the berry harvest.

For more than 20 years, VTT has been studying the health benefits of arctic berries and their antimicrobial properties. These studies have shown that berries contain antimicrobial phenolic compounds, such as ellagitannins, that kill pathogenic bacteria effectively. Such compounds can be recovered from the press cake using VTT’s patented dry and wet fractionation technologies followed by environmentally friendly hydrothermal extraction without the use of harmful solvents. 

The berry extract developed by VTT can also replace the use of synthetic preservatives in cosmetics and nanosilver formulations in wound-care products. 

“Our research has identified antimicrobial compounds in several wild berries, including sea buckthorn, bilberry, strawberry, cloudberry, lingonberry and raspberry. Large-scale production is easiest to achieve from raspberry because there is sufficient raw material. To process the seeds, it’s necessary to find a company that is experienced in this task in the value chain,” says Kirsi-Marja Oksman-Caldentey, Associate Professor and Senior Advisor at VTT.

Antibiotic-resistant bacteria are one of the greatest medical challenges

The World Health Organization (WHO) includes antibiotic-resistant bacteria among the top ten global health challenges. There has been an increase in the number of difficult-to-treat wound infections caused by methicillin-resistant Staphylococcus aureus (MRSA), a severe pathogen. MRSA is quite common in the Finnish population, with around 20% of Finns unknowingly carrying these bacteria. If MRSA enters a wound, for example during surgery, it can be fatal.  

Scientific references

Natural antimicrobials from cloudberry (Rubus chamaemorus) seeds by sanding and hydrothermal extraction. ACS Food Sci. Technol. 

Reduction of methicillin-resistant Staphylococcus aureus biofilm growth and development by arctic berry extracts. Front. Cell. Infect. Microbiol.

Sanguiin H-6 fractionated from cloudberry (Rubus chamaemorus) seeds can prevent the methicillin-resistant Staphylococcus aureus biofilm development during wound infection. Antibiotics

I found more information about VTT on its What is VTT? webpage,

VTT is a visionary research and innovation partner for companies and society

VTT is one of Europe’s leading research institutions. We are owned by the Finnish state. We advance the utilisation and commercialisation of research and technology in commerce and society. Through scientific and technological means, we turn large global challenges into sustainable growth for businesses and society. We bring together people, business, science and technology to solve the biggest challenges of our time. This is how we create sustainable growth, jobs and wellbeing and bring exponential hope.

There’s a less exuberant description in the Wikipedia entry for the VTT Technical Research Centre of Finland, Note: Links have been removed,

VTT Technical Research Centre of Finland Ltd is a state-owned and controlled non-profit limited liability company.[5] VTT is the largest research and technology company and research centre conducting applied research in Finland. It provides research and innovation services and information for domestic and international customers and partners, both in private and public sectors.[6]

VTT is part of Finland’s innovation system and operates under the mandate of the Ministry of Economic Affairs and Employment.[7]

According to the Wikipedia entry’s ‘History’ subsection, VTT’s origin year is 1942.