Researchers at the Okinawa Institute of Science and Technology in Japan have developed a nanoplasmonic sensor that can measure cell division over extended periods and detect biomolecules with high sensitivity. The device has potential as a diagnostic test for disease biomarkers, or as a research tool to screen the effects of therapeutic molecules on cell growth.
Miniaturized devices for cell culture experiments and diagnostic tests have significant clinical and research potential. The Japanese researchers have developed a solution that employs a nanoplasmonic material. Essentially, the device consists of a glass chip that is covered with millions of gold nanostructures with silicon dioxide stalks. The researchers have dubbed the structures “nanomushrooms”.
When white light shines through the slide, the nanomushrooms absorb and scatter it, but this is affected by any materials near the nanomushrooms, such as cells or biomolecules. By analyzing how the light has changed once it has passed through this surface, the researchers can measure a wide variety of phenomena, from cell division to the presence of biomolecules, with high sensitivity.
One of the major advantages of the approach is that cells can grow on the nanoplasmonic surface for extended periods, meaning that long term cell culture analysis is possible. Many nanomaterials are toxic to cells, making them unsuitable for cell analysis devices. “Usually, when you put live cells on a nanomaterial, that material is toxic and it kills the cells,” said Nikhil Bhalla, first author of the paper in journal Advanced Biosystems. “However, using our material, cells survived for over seven days.”
“Normally, you have to add labels, such as dyes or molecules, to cells, to be able to count dividing cells,” said Bhalla. “However, with our method, the nanomushrooms can sense them directly.” The device can detect an increase in cell numbers of just 16 cells in a sample of 1000 cells, and the technique has potential for cell growth assays, such as drug screens.
However, this high sensitivity also extends to other types of bioassays. The approach also has potential in detecting biological molecules, such as antibodies, raising the possibility of a nanoplasmonic diagnostic device to detect disease biomarkers. “Using our method, it is possible to create a highly sensitive biosensor that can detect even single molecules,” said Bhalla.
Study in Advanced Biosystems: Large-Scale Nanophotonic Structures for Long-Term Monitoring of Cell Proliferation…