Multifunction in One Molecule: Mitochondrial Imaging and Photothermal & Photodynamic Cytotoxicity of Fast-Response Near-Infrared Fluorescent Probes with Aggregation-Induced Emission Characteristics

Abstract

HJS and DHJS, two near-infrared emissive and mitochondria-targeted therapy probes, have been designed. They exhibited photothermal & photodynamic cytotoxicity and aggregation-induced emission (AIE) characteristics. Interestingly, we could receive fluorescence immediately after adding the probes without washing in 1 min. They could quickly enter cancer cells and selectively localized to the mitochondria firstly. When the concentration of probes was low (<5 μM), they could respond sensitively to the mitochondrial membrane potential and would selectively enter the mitochondria with red fluorescence. However, when the concentration was high (≥5 μM), they would preferentially enter the mitochondria and have the property of dual-channel fluorescence imaging (red and near-infrared) even after 24 h. What’s more, they increased the intracellular reactive oxygen species (ROS) levels, decreased the mitochondrial membrane potentials, and then induced apoptosis, which were proved by confocal imaging and flow cytometry experiments. In addition, the results of photothermal experiment and cytotoxicity test showed that the probes had good photothermal and photodynamic toxicity to cancer cells. In vitro and in vivo experiments also proved the excellent near-infrared (NIR) imaging ability, good biocompatibility and certain inhibition of tumor growth ability of DHJS.

High-Performance Near-Infrared Aggregation-Induced Emission Luminogen with Mitophagy Regulating Capability for Multimodal Cancer Theranostics

“…The photothermal stability of TACQ (0.5 mM) was shown by negligible change after 10 on–off heating cycles by laser (635 nm, 600 mW cm –2 ; Figure C). The photothermal conversion efficiencies of TACQ and TACA were determined to be 55% and 67%, respectively (Figures D,E and S8), which are higher than most reported PTT agents. ,,− The distorted configuration of these AIEgens enlarged the intermolecular distance and loosened the molecular packing in the aggregate state benefiting to the intramolecular rotation needed to generate heat. The stronger push–pull interactions contribute to longer absorption wavelengths of TACQ and TACA, which cover the excitation wavelength (635 nm) better.…”

The fast-growing field of photo-driven theranostics based on aggregation-induced emission

“…In this regard, a series of structurally twisted and charged AIEgens were reported for high-performance multimodal theranostic applications in the form of single-component AIE dots. [291][292][293][294][295][296] As a representative example, three positively charged AIE compounds named TAM, TSAM and TSSAM were prepared (Fig. 25g).…”

Multiple Light-Activated Photodynamic Therapy of Tetraphenylethylene Derivative with AIE Characteristics for Hepatocellular Carcinoma via Dual-Organelles Targeting

“…Mitochondria in tumor cells are sensitive to ROS generation induced by PDT, which ultimately induces tumor cell apoptosis by disrupting the balance of mitochondrial ROS [36]. Recently, several AIEgens have been designed for targeting mitochondria and have exhibited remarkable photostability, high brightness, and excellent PDT effect [37][38][39][40]. However, multiple doses and repeated injections of PSs are always required for better outcomes in PDT procedures, which may lead to superfluous side effects and additional toxicity to patients [36].…”