Scientists at Ludwig-Maximilians-Universität München (LMU) have found ways to make biosensors more versatile and quicker to develop.

Biosensors are devices used in medical research and diagnostics to detect substances in the body. However, these sensors typically need to be created specifically for each new use, which can be time-consuming and costly.

The scientists describe the methods and results of this study in a paper published in Nature Nanotechnology.

The scientists created a sensor using DNA origami technology, which permits building a tiny, flexible scaffold made from DNA. This scaffold has two arms that can move like a hinge. Each arm has a special tag that glows. The scientists used a method called fluorescence resonance energy transfer (FRET) to see how far apart these tags are.

When the arms are close together, the sensor is in a closed state, but when they spread apart, it opens up to a 90-degree angle. This opening and closing change the light (fluorescence) the sensor gives off, making it easier to measure with high accuracy.

Enhanced sensitivity for new applications

The DNA origami can be set up with places where different molecules, like DNA, proteins, or antibodies, can attach. By changing how these molecules attach to the sensor, scientists can make it respond in different ways to different substances. This means the sensor can be fine-tuned for sensitivity without changing how it binds to the target molecule.

This ability to adjust the sensor's sensitivity easily is what makes it special.

“It’s relatively easy to design the origami such that several molecular interactions between target molecule and sensor are queried simultaneously,” says research leader Philip Tinnefeld in an LMU press release. "This flexibility is a major advantage of our system.”

The scientists believe that, by improving this sensor, it might detect when to release drugs based on certain conditions inside the body. This innovation could speed up the creation of new diagnostic and therapeutic tools.