Research Bits: Sept. 27

Microchip detects antibodies with drop of blood

A microchip developed by researchers at Georgia Tech and Emory University can detect antibodies in the blood with just a drop a blood. Postdoctoral fellow Neda Rafat and Assistant Professor Aniruddh Sarkar created a chip that uses electrical conductivity to detect antibodies using silver in the wells of the chip. When the blood reacts with silver agent, a circuit is completed and signals sent out. Optics — using fluorescence or light to detect antibodies — is not used. “At the heart of many diagnostics, something binds to something, and a signal is produced. That’s where the optics interact and generate a light signal,” said Sarkar, a faculty member in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory. “What Neda has done is figured out a way of making that binding event happen between a patient sample and something from the sensor itself, so that signal will be directly electronic.” The researchers reported their findings in the journal Small.

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A microchip detects Covid-19 infection electronically and can differentiate between vaccine-induced antibodies and those created as a result of a coronavirus infection. (Photo: Candler Hobbs)

Underwater camera without a battery

MIT engineers built a wireless autonomous underwater camera that does not need a battery. Instead, the camera uses sound to power its functions, which are taking color digital photographs and transmitting them to the service. The camera takes sound waves’ mechanical energy into electrical energy. The camera also uses sound waves to transmit the image data to a receiver on the surface. “One of the most exciting applications of this camera for me personally is in the context of climate monitoring. We are building climate models, but we are missing data from over 95 percent of the ocean. This technology could help us build more accurate climate models and better understand how climate change impacts the underwater world,” says Fadel Adib, associate professor in the Department of Electrical Engineering and Computer Science and director of the Signal Kinetics group in the MIT Media Lab in a news alert. Adib is also the senior author of the paper, which appeared in Nature.

Wood used for biodegradable electronics

A natural raw material like wood may be part of the solution for making electronics more environmentally friendly. E-waste is a huge a problem for countries around the globe. The voluminous waste is often toxic. A research team at Empa and at ETH’s Institute for Building Materials developed a method for etching into wood and making wooden surfaces electrically conductive. The team used process called laser-induced graphitization, which heats and induces the wood to form of electrically conductive graphite. “The density of wood varies depending on the tree species and growth,” says Christopher Dreimol, first author of the study. “The result can be very uneven graphitization.” To address this problem and avoid burning the wood, research team used iron as a catalyst to make the process gentler and the surface more homogeneous. The team produced trial electronic components from spruce, cherry and beech veneers less than half a millimeter thick, using their new method.