The fabrication of highly effective photosensitizers has received considerable attention because of their attractive functions and applications in the fields of photodynamic therapy, photosynthesis, photocatalysis, et...The fabrication of highly effective photosensitizers has received considerable attention because of their attractive functions and applications in the fields of photodynamic therapy, photosynthesis, photocatalysis, etc. Thus, it is highly desirable to develop a new approach to enhance photosensitization efficiency.Herein, through coordination-driven self-assembly, a series of metallacycles with efficient fluorescence resonance energy transfer(FRET) were effectively constructed, which displayed higher photosensitization efficiency and photocatalytic activity than their model metallacycles without FRET due to broadband absorption and singlet energy transfer from the energy acceptor to the energy donor. Moreover, iodization of fluorophores induced a significant enhancement of the photosensitization efficiency and photocatalytic activity of the metallacycles. This research provides an efficient strategy for improving photosensitization efficiency and a promising platform for the preparation of effective photosensitizers and photocatalysts.展开更多
Singlet oxygen(^(1)O_(2))is a highly reactive oxygen species involved in numerous chemical and photochemical reactions in diferent biological systems and in particular,in photodynamic therapy(PDT).However,the quantifc...Singlet oxygen(^(1)O_(2))is a highly reactive oxygen species involved in numerous chemical and photochemical reactions in diferent biological systems and in particular,in photodynamic therapy(PDT).However,the quantifcation of^(1)O_(2) generation during in vitro and in vivo pho-tosensitization is still technically challenging.To address this problem,indirect and direct methods for^(1)O_(2)detection have been intensively studied.This review presents the available methods currently in use or under development for detecting and quantifying^(1)O_(2) generation during photosensitization.The advantages and limitations of each method will be presented.Moreover,the future trends in developing PDT-^(1)O_(2) dosimetry will be briefly discussed.展开更多
Using heavy-atom-containing xanthene dyes,benzoins can be quanti- tatively prepared by photosensitized reduction from benzils with triethyla- mine.It is an important supplement to'benzoin condensation',asp.for...Using heavy-atom-containing xanthene dyes,benzoins can be quanti- tatively prepared by photosensitized reduction from benzils with triethyla- mine.It is an important supplement to'benzoin condensation',asp.for those benzoins with electron-donating substituents.展开更多
The reaction of triplet fusion,also named triplet-triplet annihilation,has attracted a lot of research interests because of its wide applications in photocatalytic,solar cells,and bioimaging.As for the singlet oxygen ...The reaction of triplet fusion,also named triplet-triplet annihilation,has attracted a lot of research interests because of its wide applications in photocatalytic,solar cells,and bioimaging.As for the singlet oxygen photosensitization,the reactive singlet oxygen species are generated through the energy transfers from photosensitizer(PS)to ground triplet oxygen molecule.In this work,we computed the electronic coupling for singlet oxygen photosensitization using the nonadiabatic coupling from the quantum chemical calculation.Then we utilized the molecular orbital(MO)overlaps to approximate it,where the MOs were computed from isolated single molecules.As demonstrated with quantitative results,this approach well describes the distribution of the coupling strength as the function of the intermolecular distance between the sensitizer and O_(2),providing us a simple but effective way to predict the coupling of triplet fusion reactions.展开更多
Dual-functional aggregation-induced photosensitizers(AIE-PSs)with singlet oxygen generation(SOG)ability and bright fluorescence in aggregated state have received much attention in image-guided photodynamic therapy(PDT...Dual-functional aggregation-induced photosensitizers(AIE-PSs)with singlet oxygen generation(SOG)ability and bright fluorescence in aggregated state have received much attention in image-guided photodynamic therapy(PDT).However,designing an AIE-PS with both high SOG and intense fluorescence via molecular design is still challenging.In this work,we report a new nanohybrid consisting of gold nanostar(AuNS)and AIE-PS dots with enhanced fluorescence and photosensitization for theranostic applications.The spectral overlap between the extinction of AuNS and fluorescence emission of AIE-PS dots(665 nm)is carefully selected using five different AuNSs with distinct localized surface plasmon(LSPR)peaks.Results show that all the AuNS s can enhance the 1 O2 production of AIE-PS dots,among which the AuNS with LSPR peak at 585 nm exhibited the highest 1 O2 enhancement factor of15-fold with increased fluorescence brightness.To the best of our knowledge,this is the highest enhancement factor reported for the metalenhanced singlet oxygen generation systems.The Au585@AIE-PS nanodots were applied for simultaneous fluorescence imaging and photodynamic ablation of HeLa cancer cells with strongly enhanced PDT efficiency in vitro.This study provides a better understanding of the metal-enhanced AIE-PS nanohybrid systems,opening up new avenue towards advanced image-guided PDT with greatly improved efficacy.展开更多
In water, N,N′-diarylpyridinium thiazolo[5,4-d]thiazole vips(G1–G3) were encapsulated by cucurbit[8]uril(Q[8]) to construct Q[8]_(3)/G_(2) complexes, in which the encapsulated G molecules exist as an exact face-to...In water, N,N′-diarylpyridinium thiazolo[5,4-d]thiazole vips(G1–G3) were encapsulated by cucurbit[8]uril(Q[8]) to construct Q[8]_(3)/G_(2) complexes, in which the encapsulated G molecules exist as an exact face-to-face dimer. These complexation behaviors have been indicated by proton nuclear magnetic resonance(~1H NMR) spectroscopy and isothermal titration calorimetry(ITC),and have been confirmed by X-ray single crystal structural analysis of Q[8]_(3)/G2_(2). While free vips G1–G3 have no ability to sensitize singlet oxygen, they all become effective singlet oxygen sensitizers when complexed with Q[8]. By irradiation of white light, Q[8]_(3)/G_(2) complexes induced selective oxidation of aryl sulfide to aryl sulfoxide in good yields and selective oxidation of dimethyl sulfide(DMS) to dimethyl sulfoxide(DMSO) in excellent yields without over-oxidation to dimethyl sulfone(DMSO_(2))even for elongated irradiation. High-yield photo-oxidation of DMS to DMSO_(2) was only achieved by irradiation of blue light in the presence of Q[8]_(3)/G1_(2), which was also effective in photobleaching of Rhodamine B in water. The higher photo-oxidation power of Q[8]_(3)/G1_(2) has been ascribed to an additional generation of reactive oxygen species besides singlet oxygen.展开更多
Nitrate renoxification significantly influences atmospheric nitrogen cycling and global OH budgets.Although numerous nitrite acid(HONO)formation pathways from nitrate photolysis have been widely reported,the influence...Nitrate renoxification significantly influences atmospheric nitrogen cycling and global OH budgets.Although numerous nitrite acid(HONO)formation pathways from nitrate photolysis have been widely reported,the influence of various environmental factors and aerosol properties on reactive nitrogen production remains largely unclear.In this work,we employed NaNO_(3)/humic acid(HA)as a model nitrate photosensitization system to investigate the crucial roles of aerosol acidity,organic fraction,and dissolved oxygen in the production of HONO,NO_(2),and NO_(2)^(-).The presence of HA at 10 mg/L resulted in a remarkable increase in HONO production rates by approximately 2–3 times and NO_(2)^(-) concentration by 3–6 times across a pH range of 5.2 to 2.0.Meanwhile,the molar fraction of gaseous HONO in total N(Ⅲ)production increased from4%to 69%as bulk-phase pH decreased from 5.2 to 2.0.The higher organic fraction(i.e.,20 and 50 mg/L HA concentration)instead inhibited HONO and NO_(2) release.The presence of dissolved oxygen was found to be adverse for reactive nitrogen production.This suggests that the HA photosensitizer promoted the secondary conversion of NO_(2) to HONO mainly via reduced ketyl radical intermediates,while superoxide radical formation might exert a negative effect.Our findings provide comprehensive insights into reactive nitrogen production from photosensitized nitrate photolysis mediated by various external and internal factors,potentially accounting for discrepancies between field observations and model simulations.展开更多
By the use of the advanced ESR technique and through comparing with BHPD, the characteristic of YHPD photosensitization is discussed in this paper in the respect of the primary process of photosensitization. The exper...By the use of the advanced ESR technique and through comparing with BHPD, the characteristic of YHPD photosensitization is discussed in this paper in the respect of the primary process of photosensitization. The experiment results showed: (ⅰ) not only ~1O_2, but also free radicals(O_2· OH and YHPD)can be formed by the aid of YHPD; and (ⅱ) as to the ability of producing ~1O_2, YHPD<BHPD, while for generating O_2 and-OH, YHPD>BHPD. Two points are indicated: first, the photosensitized damage of YHPD is interrelated to not only ~1O_2, but also free radicals (O_2. OH and YHPD); second, although the photosensitized damage of YHPD is stronger than that of BHPD, yet the photosensitized damage is negatively correlated to the yield of ~1O_2 but positively correlated to those of O_2 and OH. Based on these two points, it is suggested that activated oxygen free radicals(O_2 and. OH) instead of ~1O_2 play the main role as instantaneously activated material in the photosensitized damage of YHPD.展开更多
Photosensitization,originated from the activation of triplet states,is the basis of many photodynamic applications,but often competes with a series of nonradiative processes.Herein,we communicate a new function of dou...Photosensitization,originated from the activation of triplet states,is the basis of many photodynamic applications,but often competes with a series of nonradiative processes.Herein,we communicate a new function of double-stranded DNA(dsDNA)for label-free photosensitization switching.Up to∼70-fold singlet oxygen generation boosting was observed for SYBR Green I(SG)upon binding with dsDNA.Detailed photophysical and theoretical studies have revealed the role of dsDNA as a matrix,which could efficiently suppress the nonradiative transitions of SG.展开更多
A nanomicelle(denoted as TPGS/Ppa)was fabricated via the coassembly of the amphiphilic D-α-tocopheryl polyethylene glycol 1000 succinate(TPGS)and the hydrophobic photosensitizer pyropheophorbide a(Ppa)for photodynami...A nanomicelle(denoted as TPGS/Ppa)was fabricated via the coassembly of the amphiphilic D-α-tocopheryl polyethylene glycol 1000 succinate(TPGS)and the hydrophobic photosensitizer pyropheophorbide a(Ppa)for photodynamic therapy(PDT).The obtained nanomicelle possessed a spherical structure with a diameter of(18.0±2.2)nm and a zeta potential of approximately -18 mV.Besides,the nanomicelle exhibited excellent photostability,biocompatibility,and phototoxicity,and could effectively reach the tumor region via the enhanced permeability and retention effect.Additionally,it could be found that the TPGS/Ppa nanomicelle exhibited higher phototoxicity against 4T1 murine mammary cancer cells than free Ppa.In the 4T1 tumor-bearing mouse model,the nanomicelle showed an excellent antitumor therapeutic effect.This study develops a new type of photodynamic nanomicelle TPGS/Ppa,which can increase the accumulation of drugs and prolong their tumor retention time,providing a feasible strategy for realizing the delivery of small-molecule hydrophobic drugs and tumor PDT.展开更多
By kinetic methods, functional relation of TAN radical, produced in the process of TEMPONE trapping O2, vs. time during photosensitization was established. Accordingly relative rate constants of generating all kinds o...By kinetic methods, functional relation of TAN radical, produced in the process of TEMPONE trapping O2, vs. time during photosensitization was established. Accordingly relative rate constants of generating all kinds of active intermediates through types I and II mechanism of photosensitization can be calculated. Using the formula and experimental results, the relative rate constants of generating O2, O2 and PS2 of three kinds of perylenequinone photosensitizer: HA, HB and CP in DMF-H20 and DMSO-H2O system were calculated, and then the structure-activity relationship of perylenequinone photosensitizer and the relation between photosensitivity and solvent was studied.展开更多
Pheophorbide a (PPa), a decomposition product of chlorophyll a, is a photosensitizer. The photosensiti-zation mechanisms (Type Ⅰ and Type Ⅱ) of PPa in simple buffer solutions and in buffer solutions containing doubl...Pheophorbide a (PPa), a decomposition product of chlorophyll a, is a photosensitizer. The photosensiti-zation mechanisms (Type Ⅰ and Type Ⅱ) of PPa in simple buffer solutions and in buffer solutions containing double-layered DPPC liposomes have been studied using techniques of ESR, spin-trapping, spin-counteraction and laser flash photolysis . The results showed that adding DPPC liposomes to the buffer solution caused an increase of efficiency of generating 1O2 and PPa - by photoactivating PPa. The increase could be ascribed to the disaggregation of hydrophobic PPa caused by the addition of liposomes and the protective effect of liposomal media on the triplet state of PPa. It is concluded that the photosensitization of PPa in liposomal systems is different from that in simple aqueous solutions, and shows higher efficacy. The results will be useful to elucidating the mechanisms of photodynamic therapy of cancer.展开更多
The primary reaction of photosensitization of Hypocrellin A (HA) has been studied byusing techniques of ESR, spin-trapping and spin-counteraction. The experiments show thatHA is able to generate not only ~1O_2,but als...The primary reaction of photosensitization of Hypocrellin A (HA) has been studied byusing techniques of ESR, spin-trapping and spin-counteraction. The experiments show thatHA is able to generate not only ~1O_2,but also O_2^-·OH and HA^- which are observed for thefirst time. The conversion of generating active oxygen into generating nonoxygen free rad-ical is confirmed as well. Based on the characteristics of the primary reaction which gene-rates these active substances (transient products), it is proposed that the photosensitized dam-age for the biological system by HA is probably related to not only ~1O_2 itself, but also amultiple effect from ~1O_2 as well as O_2^-,·OH and HA^+ free radical.展开更多
This study investigates the intersystem crossing(ISC)mechanism in donor-acceptor(D-A)type distyryl-BODIPY photosensitizers,including previously reported M1(benzene donor),M2,M3(phenothiazine donors),and newly predicte...This study investigates the intersystem crossing(ISC)mechanism in donor-acceptor(D-A)type distyryl-BODIPY photosensitizers,including previously reported M1(benzene donor),M2,M3(phenothiazine donors),and newly predicted M4(triphenylamine donor),M5-M7(nitrogen-containing aliphatic rings with thiophene donors).Using computational chemistry,we analyzed their geometric configurations,spectral properties,spin-orbit coupling,and electron-hole orbitals.We found that S_(2) is a charge transfer singlet state(^(1)CT),T2is a locally excited triplet state(^(3)LE),and the S_(2)→T_(2)transition is the main ISC pathway in M2-M7,following the ^(1)CT→^(3)LE mechanism.M5-M7 show near-vertical dihedral angles between donor and acceptor in the S_(2) state relative to M2-M4,facilitating charge transfer.The strain energies in the nitrogen-containing rings of M5-M7 affect oxidation potentials and ISC.M5,with the highest strain energy,shows the lowest oxidation potential,smaller△_(ES2-T2),highest SOC,and fastest kisc,making it the most efficient predicted singlet oxygen producer.This research clarifies the structure-performance relationships of near-infrared D-A type distyryl-BODIPY photosensitizers and provides a theoretical foundation for developing heavy-atom-free photosensitizers with tuned fluorescence quantum yield and singlet oxygen quantum yield.展开更多
Pt(Ⅱ)-salophen complexes(S-1~S-4) and 9,10-diphenylanthracene(DPA) tethering pillar[5]arene derivatives(A-1 and A-2) were synthesized to act as sensitizers and annihilators for triplet-triplet annihilation upconversi...Pt(Ⅱ)-salophen complexes(S-1~S-4) and 9,10-diphenylanthracene(DPA) tethering pillar[5]arene derivatives(A-1 and A-2) were synthesized to act as sensitizers and annihilators for triplet-triplet annihilation upconversion(TTA-UC), respectively. It turned out that the pyridine cation served as a mask for the excited state of the sensitizer, the triplet states of S-2 and S-3 were significantly quenched by photo-induced electron transfer(PET) with phosphorescence quantum yield quenched from 24.4% for S-4 to 9.3% for S-3,and therefore, both S-2 and S-3 led to negligible UC emissions when traditional annihilator DPA was used as the annihilator. Delightfully, when supramolecular annihilator A-1 and A-2 were employed to include the pyridine cation, PET was significantly inhibited and the triplet states of the sensitizers were activated,TTA-UC emission was therefore boosted. The UC quantum yield of A-2/S-3 system was up to 130 times higher than that of DPA/S-3 system, and the UC emission was switchable by the addition of competitive vips.展开更多
The rapid emergence of drug-resistant bacterial strains undermines the efficacy of conventional antibiotics,necessitating the development of alternative therapies.Antimicrobial photodynamic therapy(PDT)is a promising ...The rapid emergence of drug-resistant bacterial strains undermines the efficacy of conventional antibiotics,necessitating the development of alternative therapies.Antimicrobial photodynamic therapy(PDT)is a promising approach,but its effectiveness is often limited by the suboptimal photocatalytic activity of photosensitizers.In this study,we introduce a novel photoresponsive carbon-based antibacterial agent,Ce6/g-C_(3)N_(4),which combines the photocatalytic properties of graphite-phase carbon nitride(g-C_(3)N_(4))with the photodynamic attributes of chlorin e6(Ce6).This agent,with an average particle size of 250.7 nm,demonstrates significantly enhanced photocatalytic activity.Additionally,the strong affinity of Ce6/g-C_(3)N_(4)for bacteria and efficient delivery of Ce6 result in an inhibition rate exceeding 99%against Gram-positive bacteria and excellent biofilm eradication under light irradiation.In vivo experiments reveal that Ce6/gC_(3)N_(4)effectively inhibits bacterial growth on wounds,and promotes wound healing post-light treatment,while maintaining good biocompatibility.Overall,the Ce6/g-C_(3)N_(4)antibacterial agent synergizes photodynamic and photocatalytic mechanisms,offering a new avenue for the photo-mediated,multi-strategic treatment of bacterial infections and wound healing.展开更多
Photodynamic therapy (PDT) is undoubtedly a cutting-edge strategy for precise tumor therapy because of its unprecedented superiorities, such as negligible long-lasting adverse effects, high spatial and temporal select...Photodynamic therapy (PDT) is undoubtedly a cutting-edge strategy for precise tumor therapy because of its unprecedented superiorities, such as negligible long-lasting adverse effects, high spatial and temporal selectivity, and inappreciable drug resistance. While the operation wavelengths of the commonly used photosensitizers (PSs) are located in visible or first near-infrared (NIR-I, 650–900 nm) region. The lights in these regions possess relatively low penetration depth, which makes PDT unsuitable for deep-tissue treatment. Near-infrared-II (NIR-II, 1000–1700 nm) light with high tissue penetration ability can be employed as excitation source for PDT, which provides a promising alternative for precision therapy of deep-seated tumors. However, designing NIR-II activated PSs is in its infancy, and still faces many challenges, such as severe nonradiative relaxation and difficulties in adjusting energy levels. This paper reviews the therapeutic mechanisms of PDT and recent strategies for designing NIR-II activated inorganic PSs. The inorganic NIR-II PSs are classified based on their functions (such as type II PSs, type I PSs, and PSs with specific properties), and their applications for effective and precision deep-tissue treatment are summarized comprehensively. Furthermore, the major issues of applying these PSs in clinical practices are also discussed.展开更多
Innovative anti-cancer therapies that activate the immune system show promise in combating cancers resistant to conventional treatments.Photodynamic therapy(PDT)is one such treatment,which not only directly eliminates...Innovative anti-cancer therapies that activate the immune system show promise in combating cancers resistant to conventional treatments.Photodynamic therapy(PDT)is one such treatment,which not only directly eliminates tumor cells but also functions as an in situ tumor vaccine by enhancing tumor immunogenicity and triggering anti-tumor immune responses through immunogenic cell death(ICD).However,the effectiveness of PDT in enhancing immune responses is influenced by factors,such as photosensitizers and the tumor microenvironment,particularly hypoxia.Current clinically used PDT heavily relies on oxygen(O_(2))availability and can be limited by tumor hypoxia.Additionally,the tumor immunosuppressive microenvironment induced by hypoxia affects the anti-tumor immunity of tumor-infiltrating effector T cells.Meanwhile,the immunosuppressive myeloid-lineage cells are recruited to the hypoxic tumor tissue and exhibit higher immunosuppressive capabilities under hypoxia conditions.Consequently,numerous strategies have been developed to modulate tumor hypoxia or to create hypoxia-compatible PDT,aiming to reduce the effects of tumor hypoxia on PDT-driven immunotherapy.This review investigates these strategies,including approaches to alleviate,exploit,and disregard tumor hypoxia within the context of PDT/immunotherapy.It also emphasizes the role of advanced nanomedicine and its benefits in these strategies,while outlining current challenges and future prospects in the field.展开更多
This work was carried out with the aim of contributing to the treatment of cancer. Cancer is one of the most common causes of death. It constitutes a public health problem. Photodynamic therapy (PDT) is one treatment ...This work was carried out with the aim of contributing to the treatment of cancer. Cancer is one of the most common causes of death. It constitutes a public health problem. Photodynamic therapy (PDT) is one treatment option. This study contributes to the search for photosensitizing molecules used in PDT. Makaluvamines have shown interesting properties in the treatment of several human cancer cell lines. The present study analyzes the ultraviolet and visible absorption spectroscopic properties of a few Makaluvamines. These have been listed in the literature and can be in neutral or charged states (protonated and methylated). The investigation is based on quantum chemical calculations. Molecular geometries and vibrational frequencies have been calculated at the B3LYP/6-311++G(d,p) level. Absorption properties in the visible and ultraviolet spectral range are measured on optimized structures using time-dependent density functional theory (TD-DFT). The absorption spectra are obtained using the “Chemissian” software. The results of our calculations have allowed us to determine the absorption zones of the molecules studied, the energy gaps of the frontier orbitals, the main transitions associated with the absorption process, and their lifetimes. They have also identified four Makaluvamines (E, G, M, and L) that absorb in the therapeutic domain and may have photosensitizer properties.展开更多
Currently,it is still a challenge to develop an organic photosensitizer(PS)with outstanding near-infrared absorption,low O2dependence,precise tumor targeting and rapid clearance through the kidney to improve the overa...Currently,it is still a challenge to develop an organic photosensitizer(PS)with outstanding near-infrared absorption,low O2dependence,precise tumor targeting and rapid clearance through the kidney to improve the overall outcome of phototherapy.In this study,we have designed an organic PS(Nc PB)with an excellent near-infrared light absorption through a refined molecular strategy.Meanwhile,Nc PB was assembled into nanoparticles with different sizes(Nano Nc PB-1 and Nano Nc PB-0)by a supramolecular modulation strategy.As the results,the nanoparticle with an ultra-small size(Nano Nc PB-1)generated a large number of superoxide anion(O_(2)^(·-))in a low-O_(2)-dependent manner and release plenty of heat.Furthermore,the results of in vivo experiments demonstrated that Nano Nc PB-1 actively accumulated in tumor tissues and showed a 92%tumor inhibition after photodynamic and photothermal combination therapy.More importantly,Nano Nc PB-1 could be rapidly cleared from the body of mice via the renal pathway,which alleviates potential side effects of prolonged retention of PS in the circulation.展开更多
基金supported by the National Nature Science Foundation of China (No. 21871092)Program of Shanghai Outstanding Academic Leaders (No. 21XD1421200)+1 种基金the Fundamental Research Funds for the Central Universities2021 Academic Innovation Ability Enhancement Plan for Excellent Doctoral Students of East China Normal University (No. YBNLTS2021-025)。
文摘The fabrication of highly effective photosensitizers has received considerable attention because of their attractive functions and applications in the fields of photodynamic therapy, photosynthesis, photocatalysis, etc. Thus, it is highly desirable to develop a new approach to enhance photosensitization efficiency.Herein, through coordination-driven self-assembly, a series of metallacycles with efficient fluorescence resonance energy transfer(FRET) were effectively constructed, which displayed higher photosensitization efficiency and photocatalytic activity than their model metallacycles without FRET due to broadband absorption and singlet energy transfer from the energy acceptor to the energy donor. Moreover, iodization of fluorophores induced a significant enhancement of the photosensitization efficiency and photocatalytic activity of the metallacycles. This research provides an efficient strategy for improving photosensitization efficiency and a promising platform for the preparation of effective photosensitizers and photocatalysts.
基金supported by the National Natural Science Foundation of China(60978070,61036014,61175216)the Natural Science Foundation for Dis-tinguished Young Scholars of Fujian Province(2011J06022)+1 种基金the program for New Century Excel-lent Talents in University of China(NCET-10-0012)the Program for Changjiang Scholars and Inno-vative Research Team in University(IRT1115).
文摘Singlet oxygen(^(1)O_(2))is a highly reactive oxygen species involved in numerous chemical and photochemical reactions in diferent biological systems and in particular,in photodynamic therapy(PDT).However,the quantifcation of^(1)O_(2) generation during in vitro and in vivo pho-tosensitization is still technically challenging.To address this problem,indirect and direct methods for^(1)O_(2)detection have been intensively studied.This review presents the available methods currently in use or under development for detecting and quantifying^(1)O_(2) generation during photosensitization.The advantages and limitations of each method will be presented.Moreover,the future trends in developing PDT-^(1)O_(2) dosimetry will be briefly discussed.
文摘Using heavy-atom-containing xanthene dyes,benzoins can be quanti- tatively prepared by photosensitized reduction from benzils with triethyla- mine.It is an important supplement to'benzoin condensation',asp.for those benzoins with electron-donating substituents.
基金the supports from the Chinese Academy of Sciences(CAS)Institute of Chemistry,CAS+3 种基金the supports from the National Natural Science Foundation of China(No.21933011)the Beijing Municipal Science&Technology Commission(No.Z191100007219009)the K.C.Wong Education Foundationthe support from the National Natural Science Foundation of China(No.21773073)。
文摘The reaction of triplet fusion,also named triplet-triplet annihilation,has attracted a lot of research interests because of its wide applications in photocatalytic,solar cells,and bioimaging.As for the singlet oxygen photosensitization,the reactive singlet oxygen species are generated through the energy transfers from photosensitizer(PS)to ground triplet oxygen molecule.In this work,we computed the electronic coupling for singlet oxygen photosensitization using the nonadiabatic coupling from the quantum chemical calculation.Then we utilized the molecular orbital(MO)overlaps to approximate it,where the MOs were computed from isolated single molecules.As demonstrated with quantitative results,this approach well describes the distribution of the coupling strength as the function of the intermolecular distance between the sensitizer and O_(2),providing us a simple but effective way to predict the coupling of triplet fusion reactions.
基金supported by the Institute of Materials Research and Engineering under Biomimetic and Biomedical Materials program(IMRE/00-1P1400)Newcastle University(RSA/CCEAMD5010)+1 种基金National University of Singapore(R279-000-482-133)The funding from NRF Investigatorship(R279-000-444-281)is also appreciated。
文摘Dual-functional aggregation-induced photosensitizers(AIE-PSs)with singlet oxygen generation(SOG)ability and bright fluorescence in aggregated state have received much attention in image-guided photodynamic therapy(PDT).However,designing an AIE-PS with both high SOG and intense fluorescence via molecular design is still challenging.In this work,we report a new nanohybrid consisting of gold nanostar(AuNS)and AIE-PS dots with enhanced fluorescence and photosensitization for theranostic applications.The spectral overlap between the extinction of AuNS and fluorescence emission of AIE-PS dots(665 nm)is carefully selected using five different AuNSs with distinct localized surface plasmon(LSPR)peaks.Results show that all the AuNS s can enhance the 1 O2 production of AIE-PS dots,among which the AuNS with LSPR peak at 585 nm exhibited the highest 1 O2 enhancement factor of15-fold with increased fluorescence brightness.To the best of our knowledge,this is the highest enhancement factor reported for the metalenhanced singlet oxygen generation systems.The Au585@AIE-PS nanodots were applied for simultaneous fluorescence imaging and photodynamic ablation of HeLa cancer cells with strongly enhanced PDT efficiency in vitro.This study provides a better understanding of the metal-enhanced AIE-PS nanohybrid systems,opening up new avenue towards advanced image-guided PDT with greatly improved efficacy.
基金supported by the National Natural Science Foundation of China (22271090, 12204167)。
文摘In water, N,N′-diarylpyridinium thiazolo[5,4-d]thiazole vips(G1–G3) were encapsulated by cucurbit[8]uril(Q[8]) to construct Q[8]_(3)/G_(2) complexes, in which the encapsulated G molecules exist as an exact face-to-face dimer. These complexation behaviors have been indicated by proton nuclear magnetic resonance(~1H NMR) spectroscopy and isothermal titration calorimetry(ITC),and have been confirmed by X-ray single crystal structural analysis of Q[8]_(3)/G2_(2). While free vips G1–G3 have no ability to sensitize singlet oxygen, they all become effective singlet oxygen sensitizers when complexed with Q[8]. By irradiation of white light, Q[8]_(3)/G_(2) complexes induced selective oxidation of aryl sulfide to aryl sulfoxide in good yields and selective oxidation of dimethyl sulfide(DMS) to dimethyl sulfoxide(DMSO) in excellent yields without over-oxidation to dimethyl sulfone(DMSO_(2))even for elongated irradiation. High-yield photo-oxidation of DMS to DMSO_(2) was only achieved by irradiation of blue light in the presence of Q[8]_(3)/G1_(2), which was also effective in photobleaching of Rhodamine B in water. The higher photo-oxidation power of Q[8]_(3)/G1_(2) has been ascribed to an additional generation of reactive oxygen species besides singlet oxygen.
基金supported by the National Key R&D Program of China(No.2022YFC3701102)the National Natural Science Foundation of China(Nos.22376029,22176038,91744205 and 21777025)the Natural Science Foundation of Shanghai City(No.22ZR1404700).
文摘Nitrate renoxification significantly influences atmospheric nitrogen cycling and global OH budgets.Although numerous nitrite acid(HONO)formation pathways from nitrate photolysis have been widely reported,the influence of various environmental factors and aerosol properties on reactive nitrogen production remains largely unclear.In this work,we employed NaNO_(3)/humic acid(HA)as a model nitrate photosensitization system to investigate the crucial roles of aerosol acidity,organic fraction,and dissolved oxygen in the production of HONO,NO_(2),and NO_(2)^(-).The presence of HA at 10 mg/L resulted in a remarkable increase in HONO production rates by approximately 2–3 times and NO_(2)^(-) concentration by 3–6 times across a pH range of 5.2 to 2.0.Meanwhile,the molar fraction of gaseous HONO in total N(Ⅲ)production increased from4%to 69%as bulk-phase pH decreased from 5.2 to 2.0.The higher organic fraction(i.e.,20 and 50 mg/L HA concentration)instead inhibited HONO and NO_(2) release.The presence of dissolved oxygen was found to be adverse for reactive nitrogen production.This suggests that the HA photosensitizer promoted the secondary conversion of NO_(2) to HONO mainly via reduced ketyl radical intermediates,while superoxide radical formation might exert a negative effect.Our findings provide comprehensive insights into reactive nitrogen production from photosensitized nitrate photolysis mediated by various external and internal factors,potentially accounting for discrepancies between field observations and model simulations.
基金Project supported by the National Natural Science Foundation of China
文摘By the use of the advanced ESR technique and through comparing with BHPD, the characteristic of YHPD photosensitization is discussed in this paper in the respect of the primary process of photosensitization. The experiment results showed: (ⅰ) not only ~1O_2, but also free radicals(O_2· OH and YHPD)can be formed by the aid of YHPD; and (ⅱ) as to the ability of producing ~1O_2, YHPD<BHPD, while for generating O_2 and-OH, YHPD>BHPD. Two points are indicated: first, the photosensitized damage of YHPD is interrelated to not only ~1O_2, but also free radicals (O_2. OH and YHPD); second, although the photosensitized damage of YHPD is stronger than that of BHPD, yet the photosensitized damage is negatively correlated to the yield of ~1O_2 but positively correlated to those of O_2 and OH. Based on these two points, it is suggested that activated oxygen free radicals(O_2 and. OH) instead of ~1O_2 play the main role as instantaneously activated material in the photosensitized damage of YHPD.
基金support from the National Natural Science Foundation of China(nos.21874093 and 21522505)the Fundamental Research Funds for the Central China Universities(no.2018SCUH0075).
文摘Photosensitization,originated from the activation of triplet states,is the basis of many photodynamic applications,but often competes with a series of nonradiative processes.Herein,we communicate a new function of double-stranded DNA(dsDNA)for label-free photosensitization switching.Up to∼70-fold singlet oxygen generation boosting was observed for SYBR Green I(SG)upon binding with dsDNA.Detailed photophysical and theoretical studies have revealed the role of dsDNA as a matrix,which could efficiently suppress the nonradiative transitions of SG.
文摘A nanomicelle(denoted as TPGS/Ppa)was fabricated via the coassembly of the amphiphilic D-α-tocopheryl polyethylene glycol 1000 succinate(TPGS)and the hydrophobic photosensitizer pyropheophorbide a(Ppa)for photodynamic therapy(PDT).The obtained nanomicelle possessed a spherical structure with a diameter of(18.0±2.2)nm and a zeta potential of approximately -18 mV.Besides,the nanomicelle exhibited excellent photostability,biocompatibility,and phototoxicity,and could effectively reach the tumor region via the enhanced permeability and retention effect.Additionally,it could be found that the TPGS/Ppa nanomicelle exhibited higher phototoxicity against 4T1 murine mammary cancer cells than free Ppa.In the 4T1 tumor-bearing mouse model,the nanomicelle showed an excellent antitumor therapeutic effect.This study develops a new type of photodynamic nanomicelle TPGS/Ppa,which can increase the accumulation of drugs and prolong their tumor retention time,providing a feasible strategy for realizing the delivery of small-molecule hydrophobic drugs and tumor PDT.
基金Project supported by the National Natural Science Foundation of China.
文摘By kinetic methods, functional relation of TAN radical, produced in the process of TEMPONE trapping O2, vs. time during photosensitization was established. Accordingly relative rate constants of generating all kinds of active intermediates through types I and II mechanism of photosensitization can be calculated. Using the formula and experimental results, the relative rate constants of generating O2, O2 and PS2 of three kinds of perylenequinone photosensitizer: HA, HB and CP in DMF-H20 and DMSO-H2O system were calculated, and then the structure-activity relationship of perylenequinone photosensitizer and the relation between photosensitivity and solvent was studied.
基金Project supported by the National Natural Science Foundation of China (Grant No. 39830090)
文摘Pheophorbide a (PPa), a decomposition product of chlorophyll a, is a photosensitizer. The photosensiti-zation mechanisms (Type Ⅰ and Type Ⅱ) of PPa in simple buffer solutions and in buffer solutions containing double-layered DPPC liposomes have been studied using techniques of ESR, spin-trapping, spin-counteraction and laser flash photolysis . The results showed that adding DPPC liposomes to the buffer solution caused an increase of efficiency of generating 1O2 and PPa - by photoactivating PPa. The increase could be ascribed to the disaggregation of hydrophobic PPa caused by the addition of liposomes and the protective effect of liposomal media on the triplet state of PPa. It is concluded that the photosensitization of PPa in liposomal systems is different from that in simple aqueous solutions, and shows higher efficacy. The results will be useful to elucidating the mechanisms of photodynamic therapy of cancer.
基金the National Natural Science Foundation of China.
文摘The primary reaction of photosensitization of Hypocrellin A (HA) has been studied byusing techniques of ESR, spin-trapping and spin-counteraction. The experiments show thatHA is able to generate not only ~1O_2,but also O_2^-·OH and HA^- which are observed for thefirst time. The conversion of generating active oxygen into generating nonoxygen free rad-ical is confirmed as well. Based on the characteristics of the primary reaction which gene-rates these active substances (transient products), it is proposed that the photosensitized dam-age for the biological system by HA is probably related to not only ~1O_2 itself, but also amultiple effect from ~1O_2 as well as O_2^-,·OH and HA^+ free radical.
基金financially supported by the Fundamental Research Funds for the Central Universities(No.DUT20RC(3)076)Natural Science Foundation of Liaoning Province(No.2020-MS293)。
文摘This study investigates the intersystem crossing(ISC)mechanism in donor-acceptor(D-A)type distyryl-BODIPY photosensitizers,including previously reported M1(benzene donor),M2,M3(phenothiazine donors),and newly predicted M4(triphenylamine donor),M5-M7(nitrogen-containing aliphatic rings with thiophene donors).Using computational chemistry,we analyzed their geometric configurations,spectral properties,spin-orbit coupling,and electron-hole orbitals.We found that S_(2) is a charge transfer singlet state(^(1)CT),T2is a locally excited triplet state(^(3)LE),and the S_(2)→T_(2)transition is the main ISC pathway in M2-M7,following the ^(1)CT→^(3)LE mechanism.M5-M7 show near-vertical dihedral angles between donor and acceptor in the S_(2) state relative to M2-M4,facilitating charge transfer.The strain energies in the nitrogen-containing rings of M5-M7 affect oxidation potentials and ISC.M5,with the highest strain energy,shows the lowest oxidation potential,smaller△_(ES2-T2),highest SOC,and fastest kisc,making it the most efficient predicted singlet oxygen producer.This research clarifies the structure-performance relationships of near-infrared D-A type distyryl-BODIPY photosensitizers and provides a theoretical foundation for developing heavy-atom-free photosensitizers with tuned fluorescence quantum yield and singlet oxygen quantum yield.
基金supported by the National Natural Science Foundation of China (Nos. 22171194, 21971169, 92056116 and 21871194)the Fundamental Research Funds for the Central Universities (No. 20826041D4117)the Science & Technology Department of Sichuan Province (Nos. 2022YFH0095 and 2021ZYD0052)。
文摘Pt(Ⅱ)-salophen complexes(S-1~S-4) and 9,10-diphenylanthracene(DPA) tethering pillar[5]arene derivatives(A-1 and A-2) were synthesized to act as sensitizers and annihilators for triplet-triplet annihilation upconversion(TTA-UC), respectively. It turned out that the pyridine cation served as a mask for the excited state of the sensitizer, the triplet states of S-2 and S-3 were significantly quenched by photo-induced electron transfer(PET) with phosphorescence quantum yield quenched from 24.4% for S-4 to 9.3% for S-3,and therefore, both S-2 and S-3 led to negligible UC emissions when traditional annihilator DPA was used as the annihilator. Delightfully, when supramolecular annihilator A-1 and A-2 were employed to include the pyridine cation, PET was significantly inhibited and the triplet states of the sensitizers were activated,TTA-UC emission was therefore boosted. The UC quantum yield of A-2/S-3 system was up to 130 times higher than that of DPA/S-3 system, and the UC emission was switchable by the addition of competitive vips.
基金supported by the Natural Science Foundation of the Jiangsu Higher Education Institutes of China(No.22KJB530006)Hainan Provincial Natural Science Foundation of China(No.824QN267)。
文摘The rapid emergence of drug-resistant bacterial strains undermines the efficacy of conventional antibiotics,necessitating the development of alternative therapies.Antimicrobial photodynamic therapy(PDT)is a promising approach,but its effectiveness is often limited by the suboptimal photocatalytic activity of photosensitizers.In this study,we introduce a novel photoresponsive carbon-based antibacterial agent,Ce6/g-C_(3)N_(4),which combines the photocatalytic properties of graphite-phase carbon nitride(g-C_(3)N_(4))with the photodynamic attributes of chlorin e6(Ce6).This agent,with an average particle size of 250.7 nm,demonstrates significantly enhanced photocatalytic activity.Additionally,the strong affinity of Ce6/g-C_(3)N_(4)for bacteria and efficient delivery of Ce6 result in an inhibition rate exceeding 99%against Gram-positive bacteria and excellent biofilm eradication under light irradiation.In vivo experiments reveal that Ce6/gC_(3)N_(4)effectively inhibits bacterial growth on wounds,and promotes wound healing post-light treatment,while maintaining good biocompatibility.Overall,the Ce6/g-C_(3)N_(4)antibacterial agent synergizes photodynamic and photocatalytic mechanisms,offering a new avenue for the photo-mediated,multi-strategic treatment of bacterial infections and wound healing.
基金supported by the National Natural Science Foundation of China(Nos.22175098,52373142)the Jiangsu Planned Projects for Postdoctoral Research Funds(No.2021K114B)the Huali Talents Program of Nanjing University of Posts and Telecommunications,the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX23_0984)。
文摘Photodynamic therapy (PDT) is undoubtedly a cutting-edge strategy for precise tumor therapy because of its unprecedented superiorities, such as negligible long-lasting adverse effects, high spatial and temporal selectivity, and inappreciable drug resistance. While the operation wavelengths of the commonly used photosensitizers (PSs) are located in visible or first near-infrared (NIR-I, 650–900 nm) region. The lights in these regions possess relatively low penetration depth, which makes PDT unsuitable for deep-tissue treatment. Near-infrared-II (NIR-II, 1000–1700 nm) light with high tissue penetration ability can be employed as excitation source for PDT, which provides a promising alternative for precision therapy of deep-seated tumors. However, designing NIR-II activated PSs is in its infancy, and still faces many challenges, such as severe nonradiative relaxation and difficulties in adjusting energy levels. This paper reviews the therapeutic mechanisms of PDT and recent strategies for designing NIR-II activated inorganic PSs. The inorganic NIR-II PSs are classified based on their functions (such as type II PSs, type I PSs, and PSs with specific properties), and their applications for effective and precision deep-tissue treatment are summarized comprehensively. Furthermore, the major issues of applying these PSs in clinical practices are also discussed.
基金supported by the Qin Chuangyuan Traditional Chinese Medicine(TCM)and Innovation Research and Development Project of Shaanxi Provincial Administration of TCM(No.2022-QCYZH-017)Natural Science Foundation of Zhejiang Province(No.LY24E030010)+5 种基金Natural Science Foundation of Shaanxi Province(Nos.2022JM183,2024JC-YBMS-272)the Shaanxi Fundamental Science Research Project for Chemistry&Biology(No.22JHQ072)Shaanxi Provincial Key R&D Program(No.2022SF-342HZ)the Fundamental Research Funds for the Central Universities(Nos.xzy012022037,xzy012023002)the Postdoctoral Science Foundation of Shaanxi Province(No.2023BSHYDZZ05)Foundation by Shaanxi Provincial Administration of TCM(No.2021-ZZ-JC032)。
文摘Innovative anti-cancer therapies that activate the immune system show promise in combating cancers resistant to conventional treatments.Photodynamic therapy(PDT)is one such treatment,which not only directly eliminates tumor cells but also functions as an in situ tumor vaccine by enhancing tumor immunogenicity and triggering anti-tumor immune responses through immunogenic cell death(ICD).However,the effectiveness of PDT in enhancing immune responses is influenced by factors,such as photosensitizers and the tumor microenvironment,particularly hypoxia.Current clinically used PDT heavily relies on oxygen(O_(2))availability and can be limited by tumor hypoxia.Additionally,the tumor immunosuppressive microenvironment induced by hypoxia affects the anti-tumor immunity of tumor-infiltrating effector T cells.Meanwhile,the immunosuppressive myeloid-lineage cells are recruited to the hypoxic tumor tissue and exhibit higher immunosuppressive capabilities under hypoxia conditions.Consequently,numerous strategies have been developed to modulate tumor hypoxia or to create hypoxia-compatible PDT,aiming to reduce the effects of tumor hypoxia on PDT-driven immunotherapy.This review investigates these strategies,including approaches to alleviate,exploit,and disregard tumor hypoxia within the context of PDT/immunotherapy.It also emphasizes the role of advanced nanomedicine and its benefits in these strategies,while outlining current challenges and future prospects in the field.
文摘This work was carried out with the aim of contributing to the treatment of cancer. Cancer is one of the most common causes of death. It constitutes a public health problem. Photodynamic therapy (PDT) is one treatment option. This study contributes to the search for photosensitizing molecules used in PDT. Makaluvamines have shown interesting properties in the treatment of several human cancer cell lines. The present study analyzes the ultraviolet and visible absorption spectroscopic properties of a few Makaluvamines. These have been listed in the literature and can be in neutral or charged states (protonated and methylated). The investigation is based on quantum chemical calculations. Molecular geometries and vibrational frequencies have been calculated at the B3LYP/6-311++G(d,p) level. Absorption properties in the visible and ultraviolet spectral range are measured on optimized structures using time-dependent density functional theory (TD-DFT). The absorption spectra are obtained using the “Chemissian” software. The results of our calculations have allowed us to determine the absorption zones of the molecules studied, the energy gaps of the frontier orbitals, the main transitions associated with the absorption process, and their lifetimes. They have also identified four Makaluvamines (E, G, M, and L) that absorb in the therapeutic domain and may have photosensitizer properties.
基金the National Natural Science Foundation of China(Nos.T2322004 and 22078066)。
文摘Currently,it is still a challenge to develop an organic photosensitizer(PS)with outstanding near-infrared absorption,low O2dependence,precise tumor targeting and rapid clearance through the kidney to improve the overall outcome of phototherapy.In this study,we have designed an organic PS(Nc PB)with an excellent near-infrared light absorption through a refined molecular strategy.Meanwhile,Nc PB was assembled into nanoparticles with different sizes(Nano Nc PB-1 and Nano Nc PB-0)by a supramolecular modulation strategy.As the results,the nanoparticle with an ultra-small size(Nano Nc PB-1)generated a large number of superoxide anion(O_(2)^(·-))in a low-O_(2)-dependent manner and release plenty of heat.Furthermore,the results of in vivo experiments demonstrated that Nano Nc PB-1 actively accumulated in tumor tissues and showed a 92%tumor inhibition after photodynamic and photothermal combination therapy.More importantly,Nano Nc PB-1 could be rapidly cleared from the body of mice via the renal pathway,which alleviates potential side effects of prolonged retention of PS in the circulation.
