Label-Free Optical Sensing and Characterization of Biomolecules by D8 or D10 Metal Complexes

Abstract

The present invention provides a composition for detecting and/or characterizing a multiple-charged biomolecule comprising a charged d<8 >or d<10 >metal complex, wherein the metal complex electrostatically binds to the multiple-charged biomolecule to induce aggregation and self-assembly of the metal complex through metal . . . metal interactions, pi . . . pi interactions, or a combination of both interactions. The present invention further provides assay methods and kits for label-free optical detection and/or characterization of biomolecules carrying multiple charges, e.g., single-stranded nucleic acids, polyaspartate, polyglutamate, using a composition comprising a charged d<8 >or d<10 >metal complex.