Phenols are extremely difficult to release the hydrogen radical(H^(·))due to the disfavored O-H bond dissociation energy(BDE)and undergo O-H homolysis under strong ultraviolet-C(UVC)light.In this work,we provided...Phenols are extremely difficult to release the hydrogen radical(H^(·))due to the disfavored O-H bond dissociation energy(BDE)and undergo O-H homolysis under strong ultraviolet-C(UVC)light.In this work,we provided a method to modulate the O-H BDE of phenols byπ-conjugation to electron-donating heteroaromatics.Calculations on a phenol-cored photosensitizer(BTP-1)revealed drastic declines of O-H BDE(80.5 vs.28.1 kcal mol^(-1))by comparing the ground state(S_(0))and triplet excited state(T_(1)).Consequently,BTP-1 was sensitive to visible light and generated H^(·)after O-H scission.With glutathione(GSH)serving as an ultimate H^(·)donor,the BTP-1-based photosystem was efficient in catalyzing H^(·)generation under physiological conditions.This kind of hydrogen atom-based photochemistry is distinct from traditional typeⅠ/Ⅱphotosensitizing pathways that are electron or energy transfer-based.We applied the photosystem to solve the obstacle in hypoxia-activated prodrugs(HAPs)that face a dilemma with the heterogeneously hypoxic level of tumors.In vitro studies demonstrated that the photosystem boosted the chemotherapy performance of TH-302(a representative HAP)under moderate hypoxia.With the capability to target redox bonds in HAPs and good compatibility with near-infrared two-photon laser,the photosystem is promising for cancer precision therapy.展开更多
In artificial photosynthesis systems,synthetic diiron complexes are popular[FeFe]-hydrogenase mimics,which are attractive for the fabrication of photocatalyst-protein hybrid structures to amplify hydrogen(H2)generatio...In artificial photosynthesis systems,synthetic diiron complexes are popular[FeFe]-hydrogenase mimics,which are attractive for the fabrication of photocatalyst-protein hybrid structures to amplify hydrogen(H2)generation capability.However,constructing a highly bionic and efficient catalytic hybrid system is a major challenge.Notably,we designed an ideal hybrid nanofibrils system that incorporates the crucial components:(1)a[FeFe]-H2ase mimic,which has a three-arm architecture(named triFeFe)for more interaction sites and higher catalytic activity and(2)uniform hybrid nanofibrils as the biological environment in which cysteine-catalyst coordination and the hydrogen-bonding network play a vital role in both catalyst binding and hydrogen evolution reaction activity.The assembled hybrid nanofibrils achieve efficient H2 generation with a turnover number of 2.3×103,outperforming previously reported diiron catalyst-protein hybrid systems.Additionally,the hybrid nanofibrils work with photosynthetic thylakoids to produce H2,without extra photosensitizers or electron shuttle proteins,which advances the bioengineering of living systems for solar-driven biofuel production.展开更多
基金supported by the National Natural Science Foundation of China(22277054,22077065,21973041,22173045)the CAS-Croucher Funding Scheme for Joint Laboratories。
文摘Phenols are extremely difficult to release the hydrogen radical(H^(·))due to the disfavored O-H bond dissociation energy(BDE)and undergo O-H homolysis under strong ultraviolet-C(UVC)light.In this work,we provided a method to modulate the O-H BDE of phenols byπ-conjugation to electron-donating heteroaromatics.Calculations on a phenol-cored photosensitizer(BTP-1)revealed drastic declines of O-H BDE(80.5 vs.28.1 kcal mol^(-1))by comparing the ground state(S_(0))and triplet excited state(T_(1)).Consequently,BTP-1 was sensitive to visible light and generated H^(·)after O-H scission.With glutathione(GSH)serving as an ultimate H^(·)donor,the BTP-1-based photosystem was efficient in catalyzing H^(·)generation under physiological conditions.This kind of hydrogen atom-based photochemistry is distinct from traditional typeⅠ/Ⅱphotosensitizing pathways that are electron or energy transfer-based.We applied the photosystem to solve the obstacle in hypoxia-activated prodrugs(HAPs)that face a dilemma with the heterogeneously hypoxic level of tumors.In vitro studies demonstrated that the photosystem boosted the chemotherapy performance of TH-302(a representative HAP)under moderate hypoxia.With the capability to target redox bonds in HAPs and good compatibility with near-infrared two-photon laser,the photosystem is promising for cancer precision therapy.
基金the National Natural Science Foundation of China(grant nos.22077065,22021002,and 22277054)the National Key R&D Program of China(grant no.2018YFE0200700)+1 种基金the China Postdoctoral Science Foundation(grant no.2021M703264)the Beijing National Laboratory for Molecular Sciences for financial support.
文摘In artificial photosynthesis systems,synthetic diiron complexes are popular[FeFe]-hydrogenase mimics,which are attractive for the fabrication of photocatalyst-protein hybrid structures to amplify hydrogen(H2)generation capability.However,constructing a highly bionic and efficient catalytic hybrid system is a major challenge.Notably,we designed an ideal hybrid nanofibrils system that incorporates the crucial components:(1)a[FeFe]-H2ase mimic,which has a three-arm architecture(named triFeFe)for more interaction sites and higher catalytic activity and(2)uniform hybrid nanofibrils as the biological environment in which cysteine-catalyst coordination and the hydrogen-bonding network play a vital role in both catalyst binding and hydrogen evolution reaction activity.The assembled hybrid nanofibrils achieve efficient H2 generation with a turnover number of 2.3×103,outperforming previously reported diiron catalyst-protein hybrid systems.Additionally,the hybrid nanofibrils work with photosynthetic thylakoids to produce H2,without extra photosensitizers or electron shuttle proteins,which advances the bioengineering of living systems for solar-driven biofuel production.
