A bioorthogonal assembly based on metallophilic interactions for selective imaging and PDT treatment of cancer cells

Abstract

Precise control of luminescence and singlet oxygen generation is important for selective photo-theranostic applications. In this work, bioorthogonal assembly based on d¹⁰⋯d¹⁰ metallophilic interactions was first proposed for selective cancer cell imaging and photodynamic therapy (PDT) treatment as a proof of concept. [Au(NHC)₂]⁺ (NHC = N-heterocyclic carbene) cations loaded on hyaluronic acid were selectively taken up by cancer cells. The subsequent incubation with [MX₂]⁻ (M = Au or Cu and X = halide or arylacetylide) anions led to the bioorthogonal assembly of C3 + A5/A10 in cancer cells with luminescence turn-on and singlet oxygen generation upon irradiation. This work not only demonstrates that d¹⁰⋯d¹⁰ metallophilic interactions can be readily harnessed for developing bioorthogonal assembly to realize precise cancer cell imaging and PDT, but also can stimulate the development of supramolecular interaction based bioorthogonal chemistry.