A research team from the University of St Andrews and the University of Cologne has developed a brand new wireless light source that may at some point make it possible to ‘illuminate’ the human body from the within. Such light sources could enable novel, minimally invasive means to treat and higher understand diseases that today require the implantation of bulky devices. The study was published under the title ‘Wireless Magnetoelectrically Powered Organic Light-Emitting Diodes’ in Science Advances.
The brand new approach presented by the scientists from Germany and Scotland is predicated on the combination of organic light-emitting diodes (OLEDs) on ‘acoustic antennas’. Acoustic antennas are currently being explored for various applications corresponding to the detection of low magnetic fields. As a significant advantage over electric antennas, acoustic antennas may be designed to be much smaller. OLEDs are commonly present in modern smartphones and high-end televisions and consist of thin layers of organic materials that may be applied to almost any surface. Of their work, the researchers exploit this property to deposit OLEDs directly onto the acoustic antenna, thus merging the unique properties of each platforms right into a single extremely compact device. In this fashion, the acoustic antennas function substrate and power source for the custom-developed OLED. They convert energy from a magnetic field right into a mechanical oscillation and subsequently into an electrical current by the use of an effect often known as the composite magnetoelectric effect.
The brand new devices operate at sub-megahertz frequencies, a frequency range used for instance for submarine communication, as electromagnetic fields at this frequency are only weakly absorbed by water. Nonetheless, unlike in submarines, the intended application in biomedicine requires a small device to be able to avoid a negative impact on the tissue.
Lately, optical stimulation techniques have emerged as a promising alternative to electrical stimulation because they may be more cell selective and even enable the stimulation of individual cells. Such techniques have already shown promising ends in early clinical trials, for example, to treat an otherwise untreatable eye disease.
“Our novel wireless light source combines minimal device size, low operation frequency and optical stimulation,” said Humboldt Professor Dr Malte Gather, head of the Humboldt Centre for Nano- and Biophotonics on the Department of Chemistry of the University of Cologne’s Faculty of Mathematics and Natural Sciences. “Many emerging applications require multiple sites to be stimulated independently, which is why modern brain stimulators often incorporate numerous electrodes. Within the case of our wireless light sources, the devices may be independently controlled and operated without the necessity of additional and potentially bulky electronics.”
This is feasible since the operation frequencies of various acoustic antennas may be tuned to different values. In the long run, this might allow for the person control of multiple stimulators in several parts of the body, for instance to treat tremor within the late stages of Parkinson’s disease. As a next step, the researchers aim to further reduce the dimensions of their wireless OLEDs and to check their technology in an animal model.
