Near-infrared vinyl-containing aza-BODIPY nanoparticles as photosensitizer for phototherapy

Abstract

Novel vinyl-containing pyrroles were developed by the reaction of vinyl-containing ketones with 3-phenyl-2H-azirine in the presence of LDA. Utilizing these pyrroles, asymmetric vinyl-containing azaBDPs 1–8 were prepared, avoiding to the use of Knoevenagel condensation. Solid-state structure of 7 was confirmed by X-ray crystallographic analysis, and the furan, the vinyl group and the pyrrole segment in 7 are almost coplanar, owing to the conjugation. AzaBDPs 1–8 absorb and emit beyond 685 nm, and have low fluorescence quantum yields. AzaBDPs 1–8 were found to merely possess the 1O2 production capacity. The formed azaBDP nanoparticles (7-NPs) by facile encapsulation of F127 exhibit the excellent photothermal stabilities. Noteworthily, 7-NPs show the outstanding photothermal conversion efficiency (η = 55%) in aza-BODIPY system, and can effectively kill cancer cells through the photothermal conversion, which is highly desirable for an effective and potential tumor phototherapeutic reagent.