Patent ID: 7491544

Claim:
In a method of detecting Zn(II) in a sample in the presence of interfering ions by fluorescent sensing, comprising combining the sample with a chemosensor that binds preferentially to Zn(II) in the presence of Cu(II) ions and subjecting the sample to light of a wavelength of from 350 nm to 540 nm wherein a compound having the following formula is used as a fluorescent chemosensor: wherein A is nitrogen; D 1 is carbon or nitrogen; D 2 , D 3 and D 4 are carbon or nitrogen and can be the same or different; Z 1 , Z 2 , Z 3 are the same or different, and are chiral atoms; R 1 , R 2 , and R 3 are the same or different and are hydrogen, alkyl, substituted alkyl, aryl, heteroaryl or substituted aryl and if R 3 is H, then Y 3 and R 6 are not present; Y 1 , Y 2 and Y3 are the same or different and are selected from the group consisting of (a) moieties that contain an atom that coordinates to Zn(II) and (b) chromophores capable of absorbing light, wherein at least one of Y 1 , Y 2 and Y 3 binds to zinc; wherein the moieties capable of binding to Zn(II) are selected from the group consisting of C 1 -C 20 alkyl, substituted C 1 -C 20 alkyl, aryl having up to 20 carbon atoms, heteroaryl and aryl; R 4 , R 5 and R 6 are selected from the group consisting of C 1 -C 20 alkyl, substituted C 1 -C 20 alkyl, aryl having up to 20 carbon atoms, substituted aryl, halide, hydroxyl, alkoxy, carboxyl acid groups, amino groups, and amide groups; R 4 , R 5 and R 6 are optionally connected to form at least one other ring; and detecting fluorescence when the fluorescent chemosensor binds to Zn (II).