Julolidine conjugates and methods for their preparation and use
View Patent ↗Compounds that selectively bind to copper ions in a sample and methods of preparing and using the compounds are described. Disclosed herein are planar julolidine based compounds that display characteristic absorbance in the visible and near-infrared (NIR, 700-1000 nm) region in the presence of copper ions. Methods to detect Cu 2+ ions by fluorometry and colorimetry are disclosed.
1. A bi-julolidine compound having the formula:
wherein X is an oxygen atom or a sulfur atom;
R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 8 , R 9 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 and R 18 are independently selected from the group consisting of hydrogen and alkyl; and
R 7 and R 10 are hydroxyl.
2. The compound of claim 1 , wherein the compound selectively binds to Cu 2+ in the presence of one or more different metal ions in a sample.
3. The compound of claim 1 , wherein the compound does not bind to one or more of Li + , Na + , Ba 2+ , Sr 2+ , Mg 2+ , Al 3+ , Ca 2+ , Mn 2+ , Fe 2+ , Co 2+ , Ni 3+ , Zn 2+ , Ag + , Cd 2+ , Hg 2+ or Pb 2+ .
4. The compound of claim 1 , wherein the compound exhibits one or more of the following in the presence or absence of Cu 2+ ions: different visible color, different absorption spectra or different fluorescence spectra.
5. The compound of claim 1 , wherein the compound exhibits an absorption spectra in the region having a wavelength of about 460 nanometers to about 1100 nanometers upon contacting Cu 2+ ions.
6. The compound of claim 1 , wherein the compound exhibits an absorption spectra in the region having a wavelength of about 350 nanometers to about 400 nanometers in the absence of Cu 2+ ions.