News

Crab-shell and seaweed compounds spin into yarns for sustainable and functional materials

Biobased fibres are made from two renewable marine resources and with promise in advanced applications, in wovens and medical materials, among others. The threads draw strength from the crab chitin component and flexibility from seaweed alginate.
Ravunkuorista ja merilevästä tehtyä lankaa
When the chitin (pink) and the alginate (light blue) are brought into contact, the alginate begins to wrap around the chitin particles and forms filaments that are aligned when pulled up. Photo: Rafael Grande

Researchers from Aalto University, the University of São Paulo and the University of British Columbia have found a way to make a new kind of fibre from a combination of chitin nanoparticles, extracted from residual blue crab shells and alginate, a compound found in seaweed. This new bio-based material is sturdy and has antimicrobial properties.

The team studied how differences in the concentration of each component, the size of the nanoparticles, and other variables affect the mechanical properties and spinnability of the final thread. With this information, the researchers were able to produce strong, flexible threads continuously.

Professor Orlando Rojas from the Biobased Colloids and Materials (BiCMat) team at Aalto University, says that the researchers wanted to make a fibre that combined the properties of chitin – known for its antimicrobial properties – and seaweed alginate, which forms strong gels, ’The designed material, took advantage of the strong interaction between the components, which are oppositely charged. We found that when a solution of alginate contacts a suspension of chitin nanofibers, the alginate wraps around the chitin nanoparticles, forming fibrils that align in parallel as the thread is drawn upward’.

Alginate dissolves readily in water. Brown algae have alginic acid in its cell walls, which can be converted to sodium alginate. The blue crab shells were ground and purified; then the material was partially deacetylated using simple procedures.

The research team sees great potential for the material to be used for such things as threads for surgical procedures and webs for internal tissue engineering. Other uses include pads and web-like meshes for applications on the skin, for wound healing, skin conditioning and burn treatments. ‘It’s a well-known fact that that chitin nanoparticles are antimicrobial and bioactive, for example, they have shown to help hair growth’ Rojas adds.

Rojas says that for further development, the research team is looking into scaleability after demonstrating that the threads can be formed continuously, ‘This can be eventually made scalable by using simultaneous microfiber dry-drawing from the respective suspensions’.

More information:

Professor Orlando Rojas
Aalto University & FinnCERES Materials Bioeconomy Flagship
p. 050 512 4227
[email protected]

Post-doctoral researcher Rafael Grande
Aalto University
[email protected]

Link to the paper (ACS Sustainable Chem. Eng)

  • Published:
  • Updated:

Read more news

Olli Ikkana in Otaniemi, photo by Lasse Lecklin.
Research & Art Published:

Bioinspired colours and adaptable materials - Professor Olli Ikkala's third EU project builds on living systems

Department of Applied Physics Professor Olli Ikkala received his third Advanced Grant from the European Research Council (ERC) on 11 April 2024. The funding amounts to €2.5 million and the project will run for five years.
Professor Antti Oulasvirta. Photo: Aalto University / Jaakko Kahilaniemi
Press releases, Research & Art Published:

Researchers investigate how AI could better understand humans

Antti Oulasvirta has received a EUR 2.5 million Advanced Grant by the European Research Council (ERC) for the study of user models.
Kuvituskuva, jossa kirkkain värein piirretty tyttö katsoo graafista kuviota.
Research & Art Published:

How to put education policy to the test

Finland is testing changes in national education before committing to them – and showing how randcomized controlled trials can take the guesswork out of policy-making
Olli Ikkala ja Esa Saarinen
University Published:

Olli Ikkala and Esa Saarinen found a common thread in baroque music and lecturing

Olli Ikkala will continue his research on nature-inspired materials and will find himself again as an organist after his busy research career. Esa Saarinen, on the other hand, continued to lecture the Philosophy and Systems Thinking (Filosofia ja systeemiajattelu) course to packed halls this spring. When they met, they discussed the organ and the atmosphere of the lectures.