The device, which incorporates cells inside a 3D transistor made from a soft sponge-like material inspired by native tissue structure, gives scientists the ability to study cells and tissues in new ways.
By enabling cells to grow in three dimensions, the device mimics the way that cells grow in the body far more accurately than the two-dimensional petri dish approach that has traditionally been used.
"Three-dimensional cell cultures can help us identify new treatments and know which ones to avoid, if we can accurately monitor them," said Dr Charalampos Pitsalidis, a postdoctoral researcher in the Department of Chemical Engineering & Biotechnology, and the study's first author.
Now, 3D cell and tissue cultures are an emerging field of biomedical research, enabling scientists to study the physiology of human organs and tissues in ways that have not been possible before. However, while these 3D cultures can be generated, technology that accurately assesses their functionality in real time has not been well-developed.
"The majority of the cells in our body communicate with each other by electrical signals, so in order to monitor cell cultures in the lab, we need to attach electrodes to them," said Dr Róisín Owens from Cambridge's Department of Chemical Engineering and Biotechnology. "However, electrodes are pretty clunky and difficult to attach to cell cultures, so we decided to turn the whole thing on its head and put the cells inside the electrode."
The device which Dr Owens and her colleagues developed is based on a 'scaffold' of a conducting polymer sponge, configured into an electrochemical transistor. The cells are grown within the scaffold and the entire device is then placed inside a plastic tube through which the necessary nutrients for the cells can flow. The use of the soft, sponge electrode instead of a traditional rigid metal electrode provides a more natural environment for cells, and is key to the success of organ on chip technology in predicting the response of an organ to different stimuli.
Other organ on a chip devices need to be completely taken apart in order to monitor the function of the cells, but since the Cambridge-led design allows for real-time continuous monitoring, it is possible to carry out longer-term experiments on the effects of various diseases and potential treatments.
"With this system, we can monitor the growth of the tissue, and its health in response to external drugs or toxins," said Pitsalidis. "Apart from toxicology testing, we can also induce a particular disease in the tissue, and study the key mechanisms involved in that disease or discover the right treatments."
The researchers plan to use their device to develop a 'gut on a chip' and attach it to a 'brain on a chip' in order to study the relationship between the gut microbiome and brain function as part of the IMBIBE project, funded by the European Research Council. The group claims that the device - which is described in the journal Science Advances - could ultimately lead to a body on a chip system which would simulate how various treatments affect the body as whole.