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Photobase generators (PBGs) are compounds that utilize light-sensitive chemical-protecting groups to offer spatiotemporal control of releasing organic bases upon targeted light irradiation. PBGs can be implemented as an external control to initiate anionic polymerizations such as thiol–ene Michael addition reactions. However, there are limitations for common PBGs, including a short absorption wavelength and weak base release that lead to poor efficiency in photopolymerization. Therefore, there is a great need for visible-light-triggered PBGs that are capable of releasing strong bases efficiently. Here, we report two novel BODIPY-based visible-light-sensitive PBGs for light-induced activation of the thiol–ene Michael “click” reaction and polymerization. These PBGs were designed by connecting the BODIPY-based light-sensitive protecting group with tetramethylguanidine (TMG), a strong base. Moreover, we exploited the heavy atom effect to increase the efficiency of releasing TMG and the polymerization rate. These BODIPY-based PBGs exhibit extraordinary activity toward thiol–ene Michael addition-based polymerization, and they can be used in surface coating and polymer network formation of different thiol and vinyl monomers. 

A novel macroiniferter with PEO groups was developed to prepare ABA block copolymers with temperature sensitivity. 

Abstract Chemoresistance is one of the major challenges for cancer treatment, more recently ascribed to defective mitochondrial outer membrane permeabilization (MOMP), significantly diminishing chemotherapeutic agent‐induced apoptosis. A boron‐dipyrromethene (BODIPY) chromophore‐based triarylsulfonium photoacid generator (BD‐PAG) was used to target mitochondria with the aim to regulate mitochondrial pH and further depolarize the mitochondrial membrane. Cell viability assays demonstrated the relative biocompatibility of BD‐PAG in the dark while live cell imaging suggested high accumulation in mitochondria. Specific assays indicated that BD‐PAG is capable of regulating mitochondrial pH with significant effects on mitochondrial membrane depolarization. Therapeutic tests using chlorambucil in combination with BD‐PAG revealed a new strategy in chemoresistance suppression. 

Abstract Acid‐sensing ion channels (ASICs), present in both central and peripheral neurons, respond to changes in extracellular protons. They play important roles in many symptoms and diseases, such as pain, ischemic stroke and neurodegenerative diseases. Herein, we report a novel approach to activate ASICs with the precision of light using organic photoacid generators (PAGs), which are molecules that release H⁺upon light illumination, and have been recently used in biomedical studies. The PAGs showed low toxicity in dark conditions. Under LED light illumination, ASICs activation and consequent calcium ion influx was monitored and analysed by fluorescence microscopy, and showed a strong light‐dependent response. This approach allows the activation of ASICs with the precision of light, and may be valuable to help better elucidate the molecular mechanism of ASICs and unveil their roles in physiology, pathophysiology, and behaviour.