A team of scientists at the Ateneo de Manila University in the Philippines have succeeded in converting a crab shell extract into a bioplastic that they believe can be used to make optical parts called diffraction gratings.
These are popular parts used in a wide variety of products; they essentially split light into several component colors in different directions, using a well-known property of light. They are commonly used in lasers, wavelength-division multiplexing (a fundamental component of modern telecommunications), and spectrometers.
And it is in this last family of equipment that these organic diffraction washers may have the greatest impact.
Crab shell super power
The ingredient extracted from the crab shell is called chitosan and can be used as a cheap, lightweight replacement for silicone (not silicon or silica).
Early research shows that chitosan-based diffraction gratings work just as well as silicone-based gratings. “By showing that useful optical components can be made from materials normally considered waste, we hope to contribute to improving the sustainability of optical production and reducing the amount of seafood waste that needs to be disposed of,” said research team leader Raphael A. Guerrero.
Crab shell has been highlighted for its exciting potential in many applications. The researchers considered upcycling them to create a competitor to lithium-ion, which they called “Crab Coal (opens in a new tab)“.
chitosan (opens in a new tab) has been identified as a biocompatible polymer that can be used as nanoparticles to help treat lung cancer.
Often considered a by-product of the crab industry, chitosan extracted from crab shells (and potentially other shellfish) can help positively transform the optical industry, reduce waste and improve the quality of life for crab fishermen and their families.
Research has looked at the use of chitosan as a hard material to replace silicone, and it would be interesting to see if it could be extruded on a large scale to mimic optical fiber – commonly used for wired communications.
The Philippine team’s goal is to design diffraction gratings that could be used in environmentally friendly, disposable spectrometers that can be thrown away after a single use.