A perylene diimide zwitterionic polymer for photoacoustic imaging guided photothermal/photodynamic synergistic therapy with single near-infrared irradiation

Abstract

Phototherapy has great promise for precise cancer diagnosis and effective therapy, but the development of one multifunctional nanoplatform for synergistic photodynamic therapy (PDT) and photothermal therapy (PTT) at a single excitation wavelength remains a challenge. In this work, a perylene diimide zwitterionic polymer PDS-PDI was synthesized via atom transfer radical polymerization (ATRP). This polymer was designed for photoacoustic imaging (PAI) guided synergistic PDT and PTT with single 660 nm near-infrared (NIR) light irradiation. The prepared PDS-PDI polymer presents high photothermal conversion efficiency (η ≈ 40%) and efficient singlet oxygen quantum yield (Φ_Δ ≈ 16.7%) under 660 nm laser irradiation. Polymer PDS-PDI also acts as a contrast agent for PAI, offering real-time monitoring in tumor sites. Additionally, in vitro and in vivo assays indicate that polymer PDS-PDI has good biocompatibility and effective tumor destruction ability under 660 nm laser irradiation. In brief, polymer PDS-PDI prepared in this study could be applied as a dual-mode phototherapeutic agent under single laser irradiation.