Dynamic self-assembly behavior of phosphorescent cyclometalated Pt(II) complexes of thiazole and benzothiophene into disparate nanomaterials with aggregation-induced emission as sensitive theranostic agents in vitro.

Herein, a series of orange and deep red phosphorescent cyclometalated Pt(II) complexes with thiazole- or benzothiophene- based ligands were rationally designed. Notably, thiazole-containing complexes exhibit aggregation-caused quenching (ACQ), whereas benzothiophene analogues (Pt-2a-c) display aggregation-induced emission (AIE) with a remarkable red-shift (Δλ = 207-220 nm). Upon addition of biologically relevant anions (Br-, HSO3-, ClO4-) Pt-1a and Pt-2b undergo dynamic self-assembly, which not only modulates the Pt-Pt interactions resulting in distinct phosphorescent emissions but also induces morphological transformation into needle-shaped nanorods, nanotubes, and nano-blocks. The self-assemblewas systematically characterized by 1H NMR, DLS, SEM, CLSM and DFT. Moreover, Pt-1b can distinguish DNA and RNA simultaneously by turn on emission and effectively induce early apoptosis of HeLa. Our work thus reveals the potential of these Pt(II) complexes in develping novel versatile agents for theranostics in vitro.