“It’s a well-known fact that chitin nanoparticles are antimicrobial and bioactive, for example, they have shown to help hair growth.”
The medical world could soon be using materials made from a combination of crab shell and seaweed compounds, thanks to new research from Aalto University, the University of Sao Paulo and the University of British Columbia.
The researchers from these universities have been able to find 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, according to the scientists.
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 scientists were able to produce strong, flexible threads continuously.
Professor Orlando Rojas from the Biobased Colloids and Materials team at Aalto University, said 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.”
According to the team, 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 as 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 chitin nanoparticles are antimicrobial and bioactive, for example, they have shown to help hair growth,” Rojas added.
This research is the latest in a long line of studies that have highlighted the use of shellfish waste for bio-based materials. Researchers at Canadian McGill University (@mcgillu) have modified a substance found in crustacean shells to make a biopolymer. Research assistant Thomas Di Nardo says the project is unique because it produces a “long polymer which hasn’t been used before”. Consequently, this creates stronger materials.
Due to the fact that some individuals are allergic to crustaceans, the presumed relationship between allergy and the presence of chitin in crustaceans has been investigated by many researchers.
According to a 2010 study by R.A. Muzzarelli, chitins and chitosan extracted from shellfish, if purified correctly, will be totally isolated from proteins and other contaminants, and there is no evidence of their allergenicity.
Roja said that for further development, the research team is looking into scalability after demonstrating that the threads can be formed continuously.
“This can be eventually made scalable by using simultaneous microfibre dry-drawing from the respective suspensions.”