Cuticle Biomaterials

Shrimp

Shrimp

The arthropod cuticle has been in existence for well over 500 million years. The cuticle is mostly composed of two types of polymers, proteins and chitin. Chitin is a polysaccharide that provides structural support for the cuticle. Chitin is the second most abundant natural polymer on planet earth, after cellulose (produced by plants).

Chitin is also a waste product from the seafood industry. The muscular tissues of shrimp and other shellfish are consumed by humans but the cuticle is typically removed in processing. Most of the cuticle is discarded as waste. However, there are some important new uses for arthropod cuticle in medical products.

The arthropod cuticle must contain the liquid of the arthropod open circulatory system. If an arthropod is wounded, cells in its hemolymph (arthropod blood) will attach to the cuticle, coagulate and harden to patch the wound. This process has some similarities to blood clotting and scab formation to close wounds in humans. The cuticle of arthropods provides a much better surface for blood cell adhesion than many other polymers such as cellulose. Can arthropod cuticle be used for human blood clotting?

It can. However, the proteins that can cause shellfish allergies are removed by processing to produce a material called chitosan. The chitosan is a modified chitin that tightly binds cells and charged particles. When used as a compress, it stops bleeding more rapidly and effectively than the traditional cotton gauze bandage. Chitosan bandages are more expensive than traditional gauze and are used in special situations such as severe trauma or in dental applications where the wound area is relatively small. Chitosan powder can be used directly in wounds to stop bleeding and is being tested as a material for use in minimizing long term damage to the spinal chord after trauma. Chitosan has important antibacterial properties. Pathogens will adhere to the chitosan and be prevented from circulating throughout the body.

Chitosan is also finding use in environmental protection. The properties of chitosan that bind cells will also bind soil particles. Chitosan can be used as a flocculant, a substance that causes soil particles to more rapidly sediment. In areas where the soil has been disturbed and is ‘muddying the waters’ chitosan can clear the water and improve conditions for aquatic plants and animals.

Chitosan is even used as a food additive to provide additional fiber to the diet. While marketed for weight loss, chitosan is marginally effective. In weight loss, the primary mechanism would be replacing nutrients, with the non-digetstible chitosan fiber. People who want to lose weight still need to consume less and exercise more.

The study of biomolecules of insects and other arthropods can lead to important advances in human health and environmental protection.

About jjneal

Jonathan Neal is an Associate Professor of Entomology at Purdue University and author of the textbook, Living With Insects (2010). This blog is a forum to communicate about the intersection of insects with people and policy. This is a personal blog. The opinions and materials posted here are those of the author and are in no way connected with those of my employer.
This entry was posted in Biomaterials, by jjneal. Bookmark the permalink.

One Response to Cuticle Biomaterials

  1. Pingback: Cuticle Biomaterials – Entomo Planet

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s