Could crab shells enhance wound healing?

Portuguese researchers have conducted a review into the different nanomaterials that are being tested in combination with chitosan — a sugar derived from crab and shrimp shells — for applications in the biomedical field. If the tests are successful, they could lead to breakthrough such as enhanced bone regeneration, improved wound healing and targeted drug delivery.

Chitosan is known for its biocompatible, biodegradable, antibacterial, antifungal, analgesic and haemostatic properties. This makes it a good candidate for a number of biomedical applications; however, it also has limited mechanical strength. Scientists are currently working on developing composites that combine chitosan with ‘nanofillers’, making the resulting material stronger. The researchers from Portugal’s University of Minho reviewed this work in the journal Science and Technology of Advanced Materials.

The review found that scientists are finding some success in combining bioactive glass nanoparticles with chitosan to develop synthetic bone grafts. Bioactive glass is a glass-ceramic biomaterial that binds well to physiological structures such as bone. Bone cells were found to grow relatively quickly and cover grafts made of bioactive glass and chitosan.

Graphene oxide has been used in combination with chitosan to develop ‘nanocarriers’ that can deliver drugs to target tissues, avoiding the negative side effects that conventional drugs can have on other tissues of the body. Silver nanoparticles are being tested as nanofillers in combination with chitosan to develop wound dressings with antibacterial properties. Haemoglobin, silver nanoparticles and graphene have meanwhile been combined with chitosan to develop a biosensor that can detect hydrogen peroxide — a dangerous by-product of some industrial processes.

The researchers stated that further research is needed. In particular, they noted that more focus is required on improving the dispersion of nanofillers within the chitosan matrix; understanding how these composite materials interact with host tissues in the body; and learning whether these materials can be sterilised using conventional methods and exactly how these composite materials degrade.

Despite these barriers, the researchers end their review on an optimistic note, writing, “The vast opportunities shown by these materials, allied with their incredible nanotechnology potential, is expected to revolutionize the biomedical field in the near future.”

Image © Alex Barabas