Our new article about cyanine photophysics has been published in J. Phys. Chem. A
Our article "Position Matters: How Substituents Shape Photophysics and Redox Behavior of Cyanines" is now published in J. Phys. Chem. A.
In our recent study on heptamethine cyanine (Cy7) dyes, we provide a detailed framework for the rational design of near-infrared fluorophores by investigating the specific impacts of C3'- and C4'-substitution. We demonstrate that these positions offer independent control over molecular orbitals—with C3' perturbing the HOMO and C4' the LUMO—allowing for precise tuning of the optical bandgap. Beyond spectral engineering, our results clarify that Cy7 fluorescence is primarily quenched by OH-containing solvents rather than viscosity, and we highlight how C4'-substitution significantly enhances electrochemical stability by suppressing radical dimerization. Collectively, these findings offer a powerful toolkit for engineering more robust and tunable probes for bioimaging applications.
A great and enjoyable collaboration with the Štacko group in Zurich! And hopefully the first of many more to come.
Feb 24, 2026