Researchers at The University of Western Australia are studying the teeth structure of a mollusc in the hope of copying it to develop new biosynthetic materials with far-reaching biomedical, industrial and environmental applications.
Dr Jeremy Shaw, member of the Biomineralisation Research Group at UWA's Centre for Microscopy, Characterisation and Analysis, is studying the unique teeth of chitons (pronounced kite-ons), marine molluscs that have existed for millions of years. About 700 species are found all over the world.
Chitons' teeth are toughened with iron biominerals - they are harder than steel - which allows them to graze on algae located within rock. Dr Shaw said chitons have one of the highest concentrations of iron in their bodies of any animal. The species in which Dr Shaw is interested, Acanthopleura hirtosa, is a local variety that he collects from Woodman Point. He needs very small numbers of them for his research.
The teeth of A. hirtosa are like iron-clad shovels, with even juvenile chitons of only 200 micrometers (they develop from egg and larval stages) forming these iron impregnated teeth so they can feed early in life.
"We want to work out how they form the teeth and control the deposition of minerals because this will open a way for us to design tailor-made structures that could have applications as drug delivery agents, be used in high-tech bone grafting, or be developed as surface coatings in industry and medicine," Dr Shaw said.
"These structures will be stronger, more flexible and more resistant to fracture. Studying the chiton also has applications in understanding iron metabolism in human health and, further afield, in coastal ecology." Dr Shaw is also investigating the potential of chitons to act as indicators of environmental contamination in the Swan River by studying the uptake of heavy metals within the teeth.
Unlike mammalian teeth, which are made primarily of calcium, 160 of a chiton's 1400 teeth are mineralised with iron. The teeth are located on a conveyor belt-like organ, the radula, with the oldest teeth at the ‘mouth' end, and with new teeth being constantly produced to replace those worn away whilst feeding. Over its lifetime, from five to 10 years, the chiton uses tens of thousands of teeth.