Imaging intracellular zinc by stimulated Raman scattering microscopy with a small molecule vibrational probe

pools in normal and tumorigenic RWPE-1 and -2 cells that result from changes in transporter expression and cation uptake related to cancer progression. Proof-of-concept experiments demonstrate that CSZin can also respond to high concentrations of biologically relevant paramagnetic ions, enabling turn-on detection of metals that typically quench fluorescence. The modular nature of the spiropyran-based sensor may enable facile tuning of the selectivity for sensing of other target ions. This work thus paves the way for the development of a new chemical toolbox and detection strategies, complementary to fluorescence, for biological species that are challenging to image.