Chitin, Chitosan
What is Chitosan?
Chitosan is the deacetylated form of Chitin- a naturally-occurring biopolymer found in crustacean shells, exoskeletons of insects, mushrooms and other fungi.
Chitin is the second most abundant natural polysaccharide after cellulose (the structural component of plant cell walls) with an estimated 10 billion tonnes being produced annually by the planet's living organism. Polysaccharide simply refers to a carbohydrate which is made up of multiple sugar molecules bonded together. The term "chitin" comes from the Greek, ‘khiton’, which was used to refer to a tunic or other forms of coverings.
The molecular structure of chitin is what gives it the many useful properties that make it a crucial component in shells, exoskeletons and even in the cell walls of some fungi. There are 3 types of chitin, distinguished by differences in the arrangement of their molecular chains; called alpha, beta and gamma. The alpha form, mostly found in crustaceans, has an antiparallel arrangement of its polysaccharide chains, which means that the chains alternate their direction as they stack on top of one another. Beta chitin, on the other hand, has its chains arranged in a parallel formation, meaning all chains are running in the same direction and is often found in squids. Finally, gamma chitin has a mixture of parallel and antiparallel chains and commonly found in molluscs and some fungi.
How do we make Chitosan?
Our feedstock starts off as shrimp caught in UK-government regulated waters. This is then transported to seafood processors who separate the shell from the "meat" protein for human food consumption as shrimp or scampi. CuanTec uses this shell as the feedstock for its own manufacturing process. Working closely with our suppliers, we have full traceability of the raw shell “right back to the boat”, which includes knowing which boat landed the catch, the port where it was landed and where the shrimp was processed.
Once we have the raw shell at our own site, we make Chitosan through a series of tightly-controlled steps where we use our production expertise and scientific know-how to manage the processing conditions to extract the Chitosan required for the specific applications of our growing customer base.
In the first 2 steps, we remove minerals and proteins in either order to produce high-quality chitin. It is necessary to have high-quality Chitin to ensure that the final Chitosan is of the correct high quality. Step 3 is designed to effectively deacetylate chitin to convert it to chitosan. Thereafter, the chitosan is purified and can be supplied in dry powder form or in solution form to best suit the customer application.
Potential customers are welcome onsite to view our operations and meet our team.
Chitosan attributes
There are many uses for Chitosan as a result of its wide range of physico-chemical attributes:
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Haemostatic: It helps blood to naturally and safely coagulate and is especially useful in trauma situations.
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Positive electronic charge: This enables it to clarify muddy water sources (both drinking and waste water) by causing negatively charged suspended solids to aggregate and rapidly fall out of suspension.
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Antimicrobial, antibacterial and antifungal: Another feature generated by its positive charge and the presence of the functionally active amino groups, causing it to interact with negatively charged components on the microbial membrane.
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100% Biodegradable: natural environmental conditions abound with organisms which can digest chitosan by enzymatic hydrolysis with the digestion products providing nutrients to plants and other living organism.
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Biocompatible: Chitosan is highly biocompatible due to its structural and functional similarities to glycosaminoglycans which are found in the extracellular matrix of human cells, chitosan readily forms hydrogels via cross-linking processes and is similarly biocompatible.
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Fibre and film forming: Chitosan is able to produce viscous solutions in weakly acidic conditions which, in turn, can provide the basis for casting and extruding stand-alone films and strong fibres.
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Water based solutions: at or below pH 6.5 (weakly acidic) chitosan will dissolve in water and these solutions can be applied as a coating to many substrates and subsequently dried to provide useful barrier or surface properties.
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Compatible with other biomaterials: Chitosan can be blended with other biomaterials to enhance their properties.
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Heavy metal chelation: Chitosan is able to bind to heavy metals present in contaminated water systems and this property can often be combined with its flocculation capability (noted above).
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Alkali insoluble: at pH above 7, Chitosan is insoluble, and films and fibres made from it are stable in alkaline environments.
Chitosan for biomedical use
The inherent properties of Chitosan make it a very useful ingredient for Advanced Wound Care products, where the final product has to achieve a number of jobs and where a combination of benefits (such as antibacterial and haemostatic) is desired.
Currently, the majority of Chitosan is approved for use as a biomedical device such as bandages and dressings.
Looking into the future, Chitosan also has suitable properties for drug delivery mechanisms (such as the casings of pills and drugs, where the biodegradability and biocompatibility is desired).
Importantly for the biomedical sector, CuanTec works hard to ensure consistency of product together with open transparency of the supply chain- important attributes.
Chitosan for water purification use
Chitosan, with its cationic/positive charge, provides a key functional benefit for the water purification industry- it is a powerful flocculant, as it attracts the negatively-charged waste and minerals suspended in solution and rapidly creates a sediment which is easy to dispose of.
Chitosan brings additional benefits in being biocompatible with the downstream environment.
Chitosan for horticultural/agrichemical use
Chitosan also has multiple benefits for the agriculture and horticulture sectors such as: protecting and enhancing the root system of growing plants, reducing impact of fungal infections, directly providing nutrients to the soil and the plants growing in it.
Chitosan fertilizer has been widely used in plant protection, through seed coating, soil application, and foliar spraying to promote plant growth, improve immunity, and improve the soil.