The title is Spinning toy reinvented as low-tech centrifuge A paper centrifuge that is in operation can separate parasites from blood samples. Stanford News/Kurt Hickman China Rim Tape,Tubeless Rim Tape manufacturers, welcome Tubeless Tape,Bike Rim Tape purchasers from worldwide to visit our site. Rim Tape,Tubeless Rim Tape,Tubeless Tape,Bike Rim Tape KRONYO United Co., Ltd. , https://www.kronyotaiwan.com
Published on Nature News on January 10, 2017
Original author: Devin Powell
This manual centrifuge can process blood samples and isolate pathogens such as Plasmodium.
Manu Prakash grew up in India. When he was young, he would attach two strands of rope to the cap and pull the rope to play. Now, as a physical biologist at Stanford University, he has turned this simple pull rope toy into an inexpensive tool to help diagnose malaria and other diseases.
In 2013, Prakash went to Uganda to study and then began the study. The results of the study were published in the "Nature-Biomedical Engineering" on January 10. When visiting a local health service clinic, he found that most places lacked useful centrifuges, or that there was no electricity needed for the work of the centrifuges, so it was impossible to separate blood samples for basic disease diagnosis.
"There is a clinic that uses a broken centrifuge as a door stop," Prakash said. He also won the 2016 MacArthur Prize for Talent, the inventor of origami microscopes. "After returning from Africa, we began to ask ourselves, 'Can we invent a centrifuge that only depends on manpower and does not need electricity?'"
Previously, other researchers used shuca water throwers and egg beaters to make low-tech cheap centrifuges. However, Prakash said that these devices can only reach a speed of around 1200 rpm, and the processing time of samples is too long. His team hopes to be better, so they bought a large number of rotating toys in a toy store and photographed their spinning process with a high-speed camera. The yo-yo turns too slowly (and requires training to operate), but the pull-rope toy is not only easy to operate, it can reach a speed of around 10,000 rpm, which is comparable to a commercial centrifuge. 
Researchers are very pleased with the performance of pull rope toys and began to explore the underlying mathematical principles and hope to further improve. The video shows that the string of the pull rope toy will not only be tangled together when pulled, but also will form a DNA-like spiral structure. By solving the formula describing the force behind the spiral, they got the ideal parameters for the pull rope toy, including the size of the disc and the thickness of the string, etc., and its rotation speed could reach 1 million revolutions per minute.
The speed of manpower pull does not allow it to reach this theoretical limit, but a new design developed by Prakash's laboratory can reach 125,000 revolutions per minute. Last year, they applied for the Guinness World Record for the fastest manpower equipment.
"What's special about this research is that it finds a very practical use of a simple small toy, and this use is hidden under our eyes," said Shi Zhizheng, an applied mathematician at Cambridge University in the United Kingdom.
Prakash and his team affixed plastic tubes with blood samples to optimized pull-rope toys. Their final product (named a paper centrifuge) can reach 20,000 rpm and can be The plasma was separated in half a minute and the Plasmodium was isolated within 15 minutes.
Whether the staff will be willing to spend so much time working on paper centrifuges is unknown whether in health services or in the wild. Prakash has teamed up with Boston-based non-profit medical organization PIVOT to conduct clinical trials in Madagascar. This trial will not only assess the ease of use of paper centrifuges, but also compare its reliability and durability with commercial centrifuges. Compare.
Nature Video
"We don't know yet whether paper centrifuges will succeed," said Matt Bonds, co-founder of PIVOT and an economist at Harvard University. "Convincing people to abandon modern centrifuges still requires a lot of evidence, but having an alternative to paper centrifuges can create many new possibilities."
Nature|doi:10.1038/nature.2017.21273