Multifunctional nano-photosensitizer: A carrier-free aggregation-induced emission nanoparticle with efficient photosensitization and pH-responsibility

•A new small molecule aggregation-induced emission photosensitizer (HD-APNNA) was designed and synthesized.•The molecule HD-APNNA assembled into carrier-free nano-photosensitizer (AIE-NPS).•The AIE-NPS was of pH-responsiveness.•The AIE-NPS showed a remarkable photodynamic therapeutic effect in vitro and in vivo.