Making biomolecules glow: New dye solves imaging interference problem

Biomolecules, also known as organic molecules, include sugars, proteins and lipids and are the building blocks of all life. They play a role in the structure and metabolism of all living organisms. To make them visible under a microscope, researchers use special dyes to make them glow. A research team at the University of Göttingen has now developed a new method to do this better.

Unlike conventional approaches, the luminescent dye is not added to the sample as a ready-made product. Instead, it only begins to glow as it binds to the target molecule. This solves the old problem of pre-made dyes remaining in the sample even when they are not bound to the target molecule, which interferes with imaging. The research was published in the journal Angewandte Chemie International Edition.

The new method means that the luminescent dye only glows when the labeling has been successful. This makes experiments with biomolecules clearer and easier to interpret. PhD researcher at Göttingen University and first author on the study, Dongchen Du says, "Our work takes a practical approach: instead of attaching a ready-made fluorophore, we build the fluorescent label directly where it is needed. For me, that makes chemistry both beautiful and useful." In addition, the chemical reaction takes place under relatively normal conditions. This is important for sensitive biomolecules.

The researchers were able to demonstrate that the method works with a wide range of biomolecular building blocks and structures, including sugars, lipids, amino acids and proteins. Together with researchers from the University Medical Center Göttingen (UMG), they also demonstrated the method's potential for microscopy by imaging cellular structures.

"The luminescence of the dyes, meaning how much they glow, can also be chemically modified," adds Professor Nadja Simeth-Crespi at Göttingen University. "This can help researchers tailor the system for the imaging techniques of the future."