One of the greatest challenges facing hospitals and field healthcare centres in the developing world is keeping their basic equipment running. Access to electricity or replacement parts for key machinery cannot always be relied upon. The Knowledge discusses one solution of designing incubators out of motorcycle spare parts, as these are often far easier to get hold of around the world than dedicated medical components. Now Manu Prakash at the Stanford University has designed another ingenious solution.
Centrifuges are machines that spin at very high speed to help separate samples, and are vital for a huge range of hospital tests. But they need electricity to run, and key components can be difficult to replace. Prakash has taken inspiration from an ancient toy, known as the whirligig, and produced a functional centrifuge out of incredibly simple materials – it needs only disks of paper, string, and wooden handles. His ‘paperfuge’ is ultra-low-cost, and can easily be made by readily-available materials anywhere in the world.
Despite this simplicity, the paperfuge can achieve spin rates of up to 12,500 rpm – just as good as a hospital lab machine – and so separate blood plasma from red cells and help detect diseases such as malaria, African sleeping sickness, HIV and tuberculosis.