Stanford researchers created a new device called SENSBIT to monitor molecules in the body. This device, a biosensor, measures chemical reactions inside us. It sends signals that doctors can read from outside the body. Biosensors help spot tiny substances like drugs in real time. Until now, most biosensors only worked for a short time. SENSBIT can work for up to a week inside blood vessels of rats.
The researchers shared their findings in Nature Biomedical Engineering. They tested SENSBIT in live rats and human serum. SENSBIT successfully tracked drug levels during these tests.
Research leader Tom Soh said this biosensor lasts much longer than others. It marks a big step toward better biosensors. Researchers started this work over ten years ago. They designed a molecular switch to detect small molecules in the body. A molecular switch binds to molecules and sends a readable signal. However, the body’s immune system often attacks these switches, causing them to break down.
Inspired by the Human Gut
To solve this, the researchers took ideas from the human gut. SENSBIT is designed to mimic the gut’s protection. The sensor has a 3D gold surface with tiny holes, like the gut’s microvilli, to shield its parts. Microvilli are small structures that line the gut wall. A protective coating, similar to gut mucus, stops the immune system from attacking. This design keeps SENSBIT working even after days in blood.
Tests showed SENSBIT kept over 70% of its signal after a month in human serum. It held over 60% after a week in rat blood vessels. Older devices lasted only 11 hours in blood, but SENSBIT lasted 7 days. This allows better tracking of molecules in the body. Continuous monitoring could help find diseases like infections early. It might also let doctors adjust treatments quickly. The researchers believe this work helps build a future where medicine can detect and treat issues faster.