Researchers have developed silicon chip technology similar to that found in personal computers and mobile phones to function as biosensors. It is an essential step toward performing medical diagnoses using handheld devices. The technology eliminates all complex and bulky optical instrumentation used in diagnostic labs by using tiny metal layers embedded in a microchip. As a result, the new system is nearly as small as a grain of salt and far less expensive to produce than existing diagnostic systems.
The central concept is to enable complex optical systems in modern-day chips. A commercial fluorescence-based biosensor typically includes several standard optical components such as filter sets, lenses, and gratings—the more sensitive the system, the more costly and cumbersome the setup.
It is possible to realize these complex optical biosensor systems using the same technology, with no changes to the microchip manufacturing process.
The researchers discovered that tiny metal layers already built into modern microchips could be easily adapted to exploit light’s unusual behavior when interacting with structures smaller than a single wavelength of light. The silicon chip technology detects thousands of biological substances, from bacterial DNA to hormones. These structures can be created using standard manufacturing techniques since modern microchips are already designed to be extremely small.