An international team of molecular chemists, physicists and nanomolecular scientists has found the molecule responsible for the bright white stripes of the Pacific scavenger shrimp. Study published Nature Photonics. Diederik Wiersma of the European Nonlinear Spectroscopy Laboratory published a News and Insights article in the same issue of the journal describing the team’s work and explaining why this is so important for the development of photonic materials.
Photonic materials used in solar cells, sensors and optical displays have thin white coatings that help light diffuse. Most of these materials are made using titanium dioxide and zinc oxide nanoparticles, which are toxic to humans. Therefore, scientists were looking for an organic source. To this end, they observed animals with natural white coats of fine material. In this new study, the team focused their energies on learning more about the bright white stripes in Pacific cleaner shrimp.
To learn more about the lines, the team took samples and examined them under a microscope. Then, using optical measurements, they created simulations showing how the strips interacted with light. They found that the lines were white due to a thin white coating. They also discovered that the coating consists of extremely thin layers of nanospheres tightly packed together. By monitoring the emergence of light, the researchers were able to see how the light was scattered from the angles created by the nanospheres.
They found that this optical crowding caused the strips to reflect 80% of the light hitting them. The researchers determined that the nanospheres are composed of needle-like isoxanthopterin molecules. They found that these molecules provide effective scattering even when the nanospheres are tightly packed. The study highlights the role of optical anisotropy in applying light scattering. According to the researchers, this could help develop less hazardous white coatings for optical applications.
Source: Port Altele
