Graphene Oxide Functionalized with 5-Aminophenanthroline for Selective Detection of Adenine through Fluorescence “Turn-Off–On” Response

Abstract

Decorating artificial nanomaterials for selective interaction of targets without the use of expensive antibodies or multistep molecules is of great interest in the applications of drug delivery and nanomedicine. Here, we designed a graphene oxide (GO)-based modified platform (GFM) having considerable photoluminescence (PL), which was further chemically modulated for the selective detection of a particular DNA base. In specific, GO was functionalized (GFM) with 5-aminophenanthroline (5-AP) by the heterogeneous azo coupling reaction. Then, the PL of the decorated GFM has been fully quenched by Cu(II) ions having maximum quenching efficiency. Finally, the quenched PL has been recovered by adenine molecules with high selectivity and negligible interference among various competitive biologically relevant ions and molecules. The quantum yields (Φ) and excited-state lifetime data nicely corroborate with the interaction between adenine and the GFM-Cu(II) material. This noncytotoxic material can estimate adenine as low as 4.6 × 10–7 M in aqueous solution.