New imaging technique lets scientists watch drugs work inside living cells in real time

A new window into how drugs work inside cells

Researchers from Bielefeld University and the University of Vienna have developed a powerful new microscopy technique that could transform how scientists study drug effects at the cellular level. The method — called FLIM-SIM — merges two existing technologies: Structured Illumination Microscopy (SIM), which visualizes structures too small for conventional light microscopes, and Fluorescence Lifetime Imaging Microscopy (FLIM), which tracks how long fluorescent molecules emit light — a signal that shifts depending on the cell's molecular environment, such as changes in pH.

The technique was demonstrated on a human bone cancer cell line and is already being applied within the European CHEM-SCAN project, which is exploring how chemotherapy agents can be fine-tuned to target both tumors and their metastases more effectively.

By the Numbers:

• 156 nanometers — the spatial resolution achieved by the new FLIM-SIM technique
• Captures rapid processes in living cells with a large field of view and fast imaging rates
• Funded by the European Innovation Council as part of the CHEM-SCAN project

Why it matters: Understanding exactly how drugs behave inside individual cells — and what side effects they trigger at the molecular level — is critical for developing safer, more effective treatments. This technique gives researchers a much sharper lens for that work, with direct implications for cancer therapy development and broader biomedical research.