Label-free fluorescent immunoassay for Cu2+ ion detection based on UV degradation of immunocomplex and metal ion chelates.

A mouse anti Cu2+-EDTA monoclonal antibody was used to capture EDTA chelated Cu2+ ions. Then UV radiation was utilized to degrade immunocomplex and Cu2+-EDTA chelates to release free Cu2+ ions. Based on their quenching effect to the fluorescent emission of CdSe/ZnS quantum dots, the released Cu2+ ions could be detected with ideal specificity and high sensitivity.