MONOMERIC PHTHALOCYANINE REAGENTS

Fluorescent and/or chromogenic reagents in which a phthalocyanine derivative is monomerically conjugated with an antigen, antibody, or oligonucleotide. For use as fluorophores, the free base phthalocyanine may be metallated with aluminum, silicon, phosphorous, gallium, germanium, cadmium, magnesium, tin, or zinc. For use as chromogens, the phthalocyanine may or may not be metallated. For use in aqueous solution, the phthalocyanine macrocycle should be derivatized with water-solubilizing substituents such as sulfonic acid, sulfonate, carboxylic acid, carboxylate, phosphoric acid, phosphate, phosphonate, hydroxy, phenoxy, amino, ammonium, and pyridinium substituents. To further promote disaggregation, metallation with an atom of +3 valence or higher is recommended, so that the monomer will take on an axial ligand in aqueous solution. Useful as detectable markers in immunoassays. For use in enzymatic immunoassays and cDNA assays, the monomeric phthalocyanine derivative is conjugated via an enzyme-cleavable linkage with the antigen, antibody, or oligonucleotide. Reversibly quenched embodiments are also provided, in which a cleavable linkage joins a fluorescent pathalocyanine monomer with another pathalocyanine, a heavy metal, or a paramagnetic species. Also useful as monoclonal antibody reagents provide reagents in fluorescence microscopy, flow cytometry, and photodynamic therapy.