Organometallic fluorescent sensors for nitric oxide detection and imaging

A method of detecting nitric oxide (NO) in a sample comprising contacting the sample with a complex of formula (I) or (II):

• and
• measuring a fluorescence of the resulting mixture, wherein a change in fluorescence after contact with the sample, compared to the fluorescence of the complex of formula (I) or (II) in the absence of the sample, indicates the presence of NO in the sample,
• wherein
• M is a transition metal;
• each L is a ligand independently selected from CO, tetrahydrofuran, triflate, alkoxide, nitrate, nitrito, chloro, sulfate, amine, phosphine, phosphite, pi-bound alkene, alcohol, ketone, ether, thiol, thioether, nitrile, isonitrile, amide, thioamide or a solvent;
• N—N is a bidentate nitrogen containing ligand;
• N—N—Y is a tridentate nitrogen containing ligand and Y is a metal-coordinating moiety.