When is a grain of sand not a grain of sand? When it’s a single-celled plant, or diatom, with a casing made from silica [the chemical that forms sand and glass]. Diatoms, a kind of plankton, are in the ‘nano’ scale: a thousand times smaller than a grain of sand, but their shells (pictured) have a level of sophistication that current day nanotechnologists can only dream of. The regular-shaped holes are of particular interest: if the size can be standardised then diatoms could be used for controlled drug delivery. Scientists could also take advantage of the remarkable light-bending property of these holes, creating medicines that are inactive until triggered by a laser. What's more, coating diatoms with a magnetic substance would allow them to be guided, with pinpoint accuracy, to where they are needed. Perhaps, one day, the humble diatom will give us smarter medicines.
Written by Julie Webb
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
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