These delicate-looking snowflake shapes are actually tiny mechanical claws. They’re made from a material called hydrogel (pictured in white) which swells up at certain temperatures, pulling an inner skeleton of stiff plastic into different shapes. Simply heating or cooling the devices – known as microgrippers – triggers them to ‘open’ (top), or ‘close’ (bottom). Pictured next to a one cent coin, microgrippers can be moulded (or 3D-printed) with a core of iron particles, allowing them to be guided around inside a test tube, or a human body, using magnets. Such soft robotic devices have huge potential for clinical use, including delivering drugs to diseased cells and 'clamping' areas of tissue during operations – ultimately decreasing the risk, as well as the cost, of intricate surgery.
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.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.