Unrestricted molecular motions enable mild photothermy for recurrence-resistant FLASH antitumor radiotherapy

Ultrahigh dose-rate(FLASH)radiotherapy is an emerging technology with excellent therapeutic effects and low biological toxicity.However,tumor recurrence largely impede the effectiveness of FLASH therapy.Overcoming tumor recurrence is crucial for practical FLASH applications.Here,we prepared an agarose-based thermosensitive hydrogel containing a mild photothermal agent(TPE-BBT)and a glutaminase inhibitor(CB-839).Within nanoparticles,TPE-BBT exhibits aggregation-induced emission peaked at 900 nm,while the unrestricted molecular motions endow TPE-BBT with a mild photothermy generation ability.The balanced photothermal effect and photoluminescence are ideal for phototheranostics.Upon 660-nm laser irradiation,the temperature-rising effect softens and hydrolyzes the hydrogel to release TPE-BBT and CB-839 into the tumor site for concurrent mild photothermal therapy and chemotherapy,jointly inhibiting homologous recombination repair of DNA.The enhanced FLASH radiotherapy efficiently kills the tumor tissue without recurrence and obvious systematic toxicity.This work deciphers the unrestricted molecular motions in bright organic fluorophores as a source of photothermy,and provides novel recurrence-resistant radiotherapy without adverse side effects.

Key progresses of MOE key laboratory of macromolecular synthesis and functionalization in 2023

In 2023,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results in the five research directions.First,for controllable catalytic polymerization,a new silicon-centered organoboron binary catalyst was developed for copolymerization of epoxides,and a series of cooperative organocatalysts were proposed for ring-opening copolymerization of chalcogen-rich monomers.Second,with respect to microstructure and rheology,axially encoded metafiber demonstrated its capacity for integrating multiple electronics,while artificial nacre materials showed improved strength and toughness due to interlayer entanglement.Third,concerning separating functional polymers,interfacial polymerization was monitored via aggregation-induced emission,and vacuum filtration was applied to assist interfacial polymerization.Fourth,in terms of biomedical functional polymers,we designed antibacterial materials such as a novel quaternary ammonium salt that enables polyethylene terephthalate recycling and its antibacterial function,nanozyme-armed phage proved its efficiency in combating bacterial infection,and also transition metal nanoparticles showed capacities in antibacterial treatments.We also made achievements in biomedical materials,including polymeric microneedles for minimally invasive implantation and functionalization of cardiac patches,as well as ROSresponsive/scavenging prodrug/miRNA balloon coating to promote drug delivery efficiency.Besides,methods and mechanisms of RNA labeling has been developed.Fifth,about photo-electro-magnetic functional polymers,through-space conjugation was successfully manipulated by altering subunit packing modes,room-temperature phosphorescent hydrogels were synthesized via polymerization-induced crystallization of dopant molecules,and single crystals of both fullerene and non-fullerene acceptors were grown in crystallized organogel,with their photodetection performance further explored.The related works are reviewed in this paper.