Visualization and sensing of intermolecular interactions with two‐color fluorescent probes

Abstract

We developed a new generic fluorescence sensing technology based on the change of relative intensities between two well‐separated emission bands of the novel functional 3‐hydroxychromone (3HC) dyes. A greatly enhanced self‐calibrating wavelength‐ratiometric response is obtained to all major types of non‐covalent interactions that can be used in sensing – to polarity, hydrogen bonding ability and to local electrostatic fields. This technology may find a broad range of applications – from homogeneous assays in solutions to microarrays, microfluidic devices, nanosensors and whole cell imaging systems. It allows transforming micelles or phospholipid vesicles into nanosensor devices. In cellular research a high sensitivity to membrane potentials can be obtained and the membrane changes during apoptosis detected.