AIE donor-dependent photosensitizer for enhance photodynamic antibacterial interface

Abstract

Although photosensitizers (PSs) with aggregation-induced emission (AIE) effect (AIE-PSs) can realize strong fluorescence and high production of reactive oxygen species (ROS), the effect of different AIE electron donors in AIE-PSs structure on it has rarely been reported. Herein, we explore the effect of two kinds of AIE-PSs (TPEBT-Py and TPABT-Py) with triphenylamine (TPA) and tetraphenylethylene (TPE) as AIE electron donors on their ROS generation and photodynamic antibacterial interface. Interestingly, the photodynamic activity for 1O2 generation in TPABT-Py is significantly greater than that of TPEBT-Py, indicating the photodynamic performance of AIE-PSs is affected by their AIE donors. According to the density functional theory (DFT) calculation, the singlet-triplet energy gap (△ES1T1) of TPABT-Py is smaller than that of TPEBT-Py, suggesting TPA as an electron donor is more prone to intersystem crossing (ISC) and promotes the generation of 1O2. Therefore, the utilization of TPABT-Py as a photosensitizer for photodynamic antibacterial yields much superior performance.