Pub Date : 2025-01-02DOI: 10.1016/j.jphotochem.2024.116258
Beryl C. , Amogh M.S. , Cyril Benny , P.R. Biju , Reji Philip
In this work, we investigate the linear and nonlinear optical properties of the natural dye obtained from Tectona Grandis L.f. leaves by solvent extraction. Tectona Grandis L.f. of the Verbenaceae family, which provides high-quality, high-value timber for various uses, is a major strategic element in the forestry economies of many tropical countries. We investigated the nonlinear optical properties at 532 nm using CW and pulsed (5 ns) lasers, employing the techniques of Z-scan and Spatial Self phase modulation (SSPM). Theoretical fits to the measured data under CW excitation give the third-order nonlinear absorption coefficient (βeff) in the order of 10-3 cm/W, and the nonlinear refractive index coefficient (n2) in the order of 10-6 cm2/W, respectively. The βeff and n2 values obtained for pulsed excitation are in the order of 10-8 cm/W, and 10-15 cm2/W, respectively. These values are comparable to those of efficient nonlinear optical (NLO) materials previously reported in literature, revealing the applicability of the teak leaf extract natural dye in optical limiting applications for protecting sensitive optical detectors and human eyes from hazardous laser radiation.
{"title":"Optical nonlinearity of Tectona Grandis L.f. (teak) leaf extract under continuous wave and pulsed laser excitation","authors":"Beryl C. , Amogh M.S. , Cyril Benny , P.R. Biju , Reji Philip","doi":"10.1016/j.jphotochem.2024.116258","DOIUrl":"10.1016/j.jphotochem.2024.116258","url":null,"abstract":"<div><div>In this work, we investigate the linear and nonlinear optical properties of the natural dye obtained from <em>Tectona Grandis L.f.</em> leaves by solvent extraction. <em>Tectona Grandis L.f.</em> of the Verbenaceae family, which provides high-quality, high-value timber for various uses, is a major strategic element in the forestry economies of many tropical countries. We investigated the nonlinear optical properties at 532 nm using CW and pulsed (5 ns) lasers, employing the techniques of Z-scan and Spatial Self phase modulation (SSPM). Theoretical fits to the measured data under CW excitation give the third-order nonlinear absorption coefficient (<em>β<sub>eff</sub></em>) in the order of 10<sup>-3</sup> cm/W, and the nonlinear refractive index coefficient (n<sub>2</sub>) in the order of 10<sup>-6</sup> cm<sup>2</sup>/W, respectively. The <em>β<sub>eff</sub></em> and n<sub>2</sub> values obtained for pulsed excitation are in the order of 10<sup>-8</sup> cm/W, and 10<sup>-15</sup> cm<sup>2</sup>/W, respectively. These values are comparable to those of efficient nonlinear optical (NLO) materials previously reported in literature, revealing the applicability of the teak leaf extract natural dye in optical limiting applications for protecting sensitive optical detectors and human eyes from hazardous laser radiation.</div></div>","PeriodicalId":16782,"journal":{"name":"Journal of Photochemistry and Photobiology A-chemistry","volume":"462 ","pages":"Article 116258"},"PeriodicalIF":4.1,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-02DOI: 10.1016/j.jphotochem.2024.116247
John J. Alvear-Daza , Victoria Melin , Karina G. Irvicelli , Juan C. Murillo-Sierra , Antonela Canneva , Jorge A. Donadelli , Cristian H. Campos , Cecilia C. Torres , David Contreras , Alain Celzard , Vanessa Fierro , Luis R. Pizzio , Julián A. Rengifo-Herrera
The chemical activation of sunflower seed shells (SSS) with H3PO4 led to highly porous activated carbon (ACSSSH3PO4) containing carbon-centered environmentally persistent free radicals (EPFRs), quinone functional groups, among others, and a slight graphitization degree. With high diclofenac (DFC) and ibuprofen (IBP) dark adsorption capacity (∼98 % after 1 h), ACSSSH3PO4 was evaluated as a metal-free photocatalyst using quantitative and qualitative approaches under UV and visible light irradiation. However, due to the high adsorption of both pollutants onto the solid, monitoring photocatalytic activity was impossible. For this reason, a quantitative and qualitative strategy was developed to evaluate the existence of pollutant degradation in highly porous activated carbon. On the one hand, the qualitative approach was based on the use of ATR-FTIR spectroscopy, detecting IR bands of both molecules adsorbed on the activated carbon and evaluating their intensity reduction or the apparition of new IR bands assigned to oxidized byproducts after 5 h of light irradiation. On the other hand, the quantitative approach was based on a desorption procedure to remove DFC and IBP from the ACSSSH3PO4 after 5 h of light irradiation and quantifying their concentrations by UHPLC. Thus, it was found that under irradiation for 5 h at λ > 260 nm, ACSSSH3PO4 showed 62 and 30 % degradation for adsorbed DFC and IBP, respectively, while under visible irradiation, pollutants degradation was 42–29 % and 20 %. ACSSSH3PO4 thus demonstrated significant photoinduced activity, probably due to EPFRs, quinone, and graphitic functional groups.
{"title":"Metal-free photocatalyst based on highly porous activated carbon obtained from agro-industrial residues. Characterization and photocatalytic evaluation","authors":"John J. Alvear-Daza , Victoria Melin , Karina G. Irvicelli , Juan C. Murillo-Sierra , Antonela Canneva , Jorge A. Donadelli , Cristian H. Campos , Cecilia C. Torres , David Contreras , Alain Celzard , Vanessa Fierro , Luis R. Pizzio , Julián A. Rengifo-Herrera","doi":"10.1016/j.jphotochem.2024.116247","DOIUrl":"10.1016/j.jphotochem.2024.116247","url":null,"abstract":"<div><div>The chemical activation of sunflower seed shells (SSS) with H<sub>3</sub>PO<sub>4</sub> led to highly porous activated carbon (AC<sub>SSS</sub><sup>H</sup><sub>3</sub><sup>PO</sup><sub>4</sub>) containing carbon-centered environmentally persistent free radicals (EPFRs), quinone functional groups, among others, and a slight graphitization degree. With high diclofenac (DFC) and ibuprofen (IBP) dark adsorption capacity (∼98 % after 1 h), AC<sub>SSS</sub><sup>H</sup><sub>3</sub><sup>PO</sup><sub>4</sub> was evaluated as a metal-free photocatalyst using quantitative and qualitative approaches under UV and visible light irradiation. However, due to the high adsorption of both pollutants onto the solid, monitoring photocatalytic activity was impossible. For this reason, a quantitative and qualitative strategy was developed to evaluate the existence of pollutant degradation in highly porous activated carbon. On the one hand, the qualitative approach was based on the use of ATR-FTIR spectroscopy, detecting IR bands of both molecules adsorbed on the activated carbon and evaluating their intensity reduction or the apparition of new IR bands assigned to oxidized byproducts after 5 h of light irradiation. On the other hand, the quantitative approach was based on a desorption procedure to remove DFC and IBP from the AC<sub>SSS</sub><sup>H</sup><sub>3</sub><sup>PO</sup><sub>4</sub> after 5 h of light irradiation and quantifying their concentrations by UHPLC. Thus, it was found that under irradiation for 5 h at λ > 260 nm, AC<sub>SSS</sub><sup>H</sup><sub>3</sub><sup>PO</sup><sub>4</sub> showed 62 and 30 % degradation for adsorbed DFC and IBP, respectively, while under visible irradiation, pollutants degradation was 42–29 % and 20 %. AC<sub>SSS</sub><sup>H</sup><sub>3</sub><sup>PO</sup><sub>4</sub> thus demonstrated significant photoinduced activity, probably due to EPFRs, quinone, and graphitic functional groups.</div></div>","PeriodicalId":16782,"journal":{"name":"Journal of Photochemistry and Photobiology A-chemistry","volume":"462 ","pages":"Article 116247"},"PeriodicalIF":4.1,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-02DOI: 10.1016/j.jphotochem.2024.116260
Ahmed AlSarori , Abdurrahman Mustafa , Hasan Akyıldız , Ismail Cihan Kaya , Gulcihan Guzel Kaya
In this study, non-stoichiometric FeS2 nanoparticles were synthesized via hot-injection method and evaluated as dual effect antibacterial agent. Non-stoichiometric FeS2 nanoparticles were achieved by altering the molar ratio of the precursors (i.e., Fe-source and S-source). X-ray photoelectron spectroscopy (XPS) analysis revealed that Fe/S ratio in the FeS2 nanoparticles were 1.012:2, 0.960:2, 0.905:2, and 0.900:2 for the samples with Fe-source to S-source ratios of 1/6, 1/8, 1/10, and 1/12, respectively. In the case of Fe/S: 0.900:2, the temperature increased up to about 53 °C (photothermal conversion efficiency: 52.6 %) in addition to reactive oxygen species (ROS) generation under 808 nm near-infrared (NIR) light irradiation. Based on the in vitro antibacterial activity tests, non-stoichiometric FeS2 nanoparticles exhibited promising antibacterial activity against Escherichia coli (98.00%) and Staphylococcus aureus (99.89%) due to the synergistic effects of ROS formation and hyperthermia. The non-stoichiometric FeS2 nanoparticles can be considered as high potential antibacterial material under NIR irradiation.
{"title":"Non-Stoichiometric FeS2 nanoparticles as antibacterial agents with combined photothermal and photodynamic effect","authors":"Ahmed AlSarori , Abdurrahman Mustafa , Hasan Akyıldız , Ismail Cihan Kaya , Gulcihan Guzel Kaya","doi":"10.1016/j.jphotochem.2024.116260","DOIUrl":"10.1016/j.jphotochem.2024.116260","url":null,"abstract":"<div><div>In this study, non-stoichiometric FeS<sub>2</sub> nanoparticles were synthesized <em>via</em> hot-injection method and evaluated as dual effect antibacterial agent. Non-stoichiometric FeS<sub>2</sub> nanoparticles were achieved by altering the molar ratio of the precursors (i.e., Fe-source and S-source). X-ray photoelectron spectroscopy (XPS) analysis revealed that Fe/S ratio in the FeS<sub>2</sub> nanoparticles were 1.012:2, 0.960:2, 0.905:2, and 0.900:2 for the samples with Fe-source to S-source ratios of 1/6, 1/8, 1/10, and 1/12, respectively. In the case of Fe/S: 0.900:2, the temperature increased up to about 53 °C (photothermal conversion efficiency: 52.6 %) in addition to reactive oxygen species (ROS) generation under 808 nm near-infrared (NIR) light irradiation. Based on the <em>in vitro</em> antibacterial activity tests, non-stoichiometric FeS<sub>2</sub> nanoparticles exhibited promising antibacterial activity against <em>Escherichia coli</em> (98.00%) and <em>Staphylococcus aureus</em> (99.89%) due to the synergistic effects of ROS formation and hyperthermia. The non-stoichiometric FeS<sub>2</sub> nanoparticles can be considered as high potential antibacterial material under NIR irradiation.</div></div>","PeriodicalId":16782,"journal":{"name":"Journal of Photochemistry and Photobiology A-chemistry","volume":"462 ","pages":"Article 116260"},"PeriodicalIF":4.1,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-31DOI: 10.1016/j.jphotochem.2024.116255
Léo Niederst, Xavier Allonas, Christian Ley, Issei Takahashi
In this paper, a new kind of redox additive usable in photocyclic initiating systems for radical photopolymerization is presented. Di-toluene-4-sulfonamide is shown to act as a quite efficient candidate as electron acceptor due to its high reduction potential. Its effectiveness as an electron acceptor in UV to near-IR Type III photoinitiating systems for radical photopolymerization is demonstrated by interaction with three different dyes. Its implementation into type III photoinitiators leads to a two-fold enhancement of the polymerization rate. An exhaustive photochemical study is conducted giving a thorough description of the chemical reactions, demonstrating a photocatalytic cycle in the type III photoinitiating system for two of the dyes and the ability of the di-toluene-4-sulfonamide to enhance near IR sensitivity.
{"title":"Introducing a new electron acceptor for the implementation of photocyclic initiating system for radical photopolymerization","authors":"Léo Niederst, Xavier Allonas, Christian Ley, Issei Takahashi","doi":"10.1016/j.jphotochem.2024.116255","DOIUrl":"10.1016/j.jphotochem.2024.116255","url":null,"abstract":"<div><div>In this paper, a new kind of redox additive usable in photocyclic initiating systems for radical photopolymerization is presented. Di-toluene-4-sulfonamide is shown to act as a quite efficient candidate as electron acceptor due to its high reduction potential. Its effectiveness as an electron acceptor in UV to near-IR Type III photoinitiating systems for radical photopolymerization is demonstrated by interaction with three different dyes. Its implementation into type III photoinitiators leads to a two-fold enhancement of the polymerization rate. An exhaustive photochemical study is conducted giving a thorough description of the chemical reactions, demonstrating a photocatalytic cycle in the type III photoinitiating system for two of the dyes and the ability of the di-toluene-4-sulfonamide to enhance near IR sensitivity.</div></div>","PeriodicalId":16782,"journal":{"name":"Journal of Photochemistry and Photobiology A-chemistry","volume":"462 ","pages":"Article 116255"},"PeriodicalIF":4.1,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-31DOI: 10.1016/j.jphotochem.2024.116256
Chiara Reviglio , Giorgio Volpi , Elisabeth Wyart , Betty Ciubini , Cristina Prandi , Claudia Barolo , Paolo Ettore Porporato , Claudio Garino
Six substituted imidazo[1,5-a]pyridine and imidazo[5,1-a]isoquinoline derivatives have been designed and characterized as possible fluorogenic substrates for detection and application of esterase enzymes or other ester hydrolysis conditions. The optical tunability of the fluorescent scaffold has been evaluated introducing a free carboxylic acid or the corresponding methyl ester substituent, obtaining turn-on fluorescence sensing systems with large signal-to-noise ratios and high enzymatic reactivity. The probes have been tested in fluorescence imaging experiments with endogenous and exogenous esterases.
{"title":"Imidazopyridines as fluorogenic substrates for esterase detection","authors":"Chiara Reviglio , Giorgio Volpi , Elisabeth Wyart , Betty Ciubini , Cristina Prandi , Claudia Barolo , Paolo Ettore Porporato , Claudio Garino","doi":"10.1016/j.jphotochem.2024.116256","DOIUrl":"10.1016/j.jphotochem.2024.116256","url":null,"abstract":"<div><div>Six substituted imidazo[1,5-<em>a</em>]pyridine and imidazo[5,1-<em>a</em>]isoquinoline derivatives have been designed and characterized as possible fluorogenic substrates for detection and application of esterase enzymes or other ester hydrolysis conditions. The optical tunability of the fluorescent scaffold has been evaluated introducing a free carboxylic acid or the corresponding methyl ester substituent, obtaining turn-on fluorescence sensing systems with large signal-to-noise ratios and high enzymatic reactivity. The probes have been tested in fluorescence imaging experiments with endogenous and exogenous esterases.</div></div>","PeriodicalId":16782,"journal":{"name":"Journal of Photochemistry and Photobiology A-chemistry","volume":"462 ","pages":"Article 116256"},"PeriodicalIF":4.1,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-31DOI: 10.1016/j.jphotochem.2024.116253
Dana A. Kader , Safin A. Abdalla , Sewara J. Mohammed , Dara Muhammed Aziz , Dlzar D. Ghafoor , Trefa M. Abdullah , Nian N.M. Agha , Fryad S. Mustafa , Sangar Ali Hassan
For the first time, this work demonstrates an environmentally benign and sustainable catalytic process using a TiO2@PPHs nanocomposite prepared by green synthesis. This was achieved by preparing a nanocomposite by decorating TiO2NPs with polyphenols (PPHs) extracted from black carrots (Daucus carota), which resulted in an active photocatalyst for oxidation reactions and Brilliant Green (BG) dye degradation under visible light (green LED light). The prepared TiO2@PPHs nanocomposite was comprehensively characterized by XRD, SEM, FT-IR, EDX, and BET analysis for pore-size distribution and specific surface area measurement. Zeta potential measurement and UV–visible DRS spectroscopy were also conducted. XRD and SEM with EDX analysis confirmed the crystallinity of the TiO2@PPHs nanocomposite with a particle size of 67.92 nm. Surface interactions and improved optical properties with a reduction in band gap energy from 3.04 for pure TiO2NPs to 2.02 eV for TiO2@PPHs nanocomposite make it a suitable catalyst that can be activated under green light irradiation. The catalytic activity of TiO2@PPHs was studied for the aerobic oxidation of amine to imines and degradation of BG dye in aqueous solution. The nanocomposite showed excellent efficiency in amine oxidation (up to 99 % conversion) and dye degradation (96 %). Mechanistic studies confirmed the significant role of the generated ROS, in particular hydroxyl and superoxide radicals, during these photocatalytic reactions. The TiO2@PPHs catalyst also exhibited recycling sequences with stable efficient synergistic catalytic results, which highlights light on sustainability in industrial applications.
{"title":"Green Light, green Chemistry: TiO2@PPHs nanocomposite for Eco-Friendly photocatalytic oxidation of amines and degradation of Brilliant green dye","authors":"Dana A. Kader , Safin A. Abdalla , Sewara J. Mohammed , Dara Muhammed Aziz , Dlzar D. Ghafoor , Trefa M. Abdullah , Nian N.M. Agha , Fryad S. Mustafa , Sangar Ali Hassan","doi":"10.1016/j.jphotochem.2024.116253","DOIUrl":"10.1016/j.jphotochem.2024.116253","url":null,"abstract":"<div><div>For the first time, this work demonstrates an environmentally benign and sustainable catalytic process using a TiO<sub>2</sub>@PPHs nanocomposite prepared by green synthesis. This was achieved by preparing a nanocomposite by decorating TiO<sub>2</sub>NPs with polyphenols (PPHs) extracted from black carrots (Daucus carota), which resulted in an active photocatalyst for oxidation reactions and Brilliant Green (BG) dye degradation under visible light (green LED light). The prepared TiO<sub>2</sub>@PPHs nanocomposite was comprehensively characterized by XRD, SEM, FT-IR, EDX, and BET analysis for pore-size distribution and specific surface area measurement. Zeta potential measurement and UV–visible DRS spectroscopy were also conducted. XRD and SEM with EDX analysis confirmed the crystallinity of the TiO<sub>2</sub>@PPHs nanocomposite with a particle size of 67.92 nm. Surface interactions and improved optical properties with a reduction in band gap energy from 3.04 for pure TiO<sub>2</sub>NPs to 2.02 eV for TiO<sub>2</sub>@PPHs nanocomposite make it a suitable catalyst that can be activated under green light irradiation. The catalytic activity of TiO<sub>2</sub>@PPHs was studied for the aerobic oxidation of amine to imines and degradation of BG dye in aqueous solution. The nanocomposite showed excellent efficiency in amine oxidation (up to 99 % conversion) and dye degradation (96 %). Mechanistic studies confirmed the significant role of the generated ROS, in particular hydroxyl and superoxide radicals, during these photocatalytic reactions. The TiO<sub>2</sub>@PPHs catalyst also exhibited recycling sequences with stable efficient synergistic catalytic results, which highlights light on sustainability in industrial applications.</div></div>","PeriodicalId":16782,"journal":{"name":"Journal of Photochemistry and Photobiology A-chemistry","volume":"462 ","pages":"Article 116253"},"PeriodicalIF":4.1,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zinc methyl 31-demethyl-bacteriopheophorbides-d lacking the 7-methyl or 8-ethyl group were prepared from chlorophyll-b or a, respectively, via Pinnick oxidation of a formyl to carboxy group at the 7- or 8-position followed by its pyrolysis. The substitution effects of the 7-methyl and 8-ethyl groups on the optical properties of the zinc chlorophyll derivatives in THF and in an aqueous Triton X-100 micellar solution were investigated. In tetrahydrofuran (THF), all the synthetic zinc complexes were monomeric to give sharp electronic absorption bands and highly fluorescent emission bands. The Qy absorption and fluorescence emission maxima were hypsochromically shifted in the order of zinc 7-methyl-8-ethyl-, 7-methyl-8-deethyl-, and 7-demethyl-8-ethyl-chlorins, but no significant effects of the 7- or 8-dealkylation were observed in the Qx and Soret bands. In the aqueous micelles, the three zinc 3-hydroxymethyl-131-oxo-chlorins self-aggregated to give broadened and red-shifted absorption bands, which were similar as in the self-aggregates of bacteriochlorophylls-c/d/e in the major light-harvesting antennas of green photosynthetic bacteria (chlorosomes). The dealkylation moved the red-shifted Qy maxima of the self-aggregates to shorter wavelengths than that of the alkylated compound. The substitution effect was comparable to the bathochromic shifts in the Qy bands of the bacteriochlorophyll self-aggregates in chlorosomes by the sequential methylation at the 8-ethyl terminal. The dealkylation slightly suppressed the self-aggregation ability, revealing the CH–π interaction of the alkyl groups with the chlorin chromophore in the self-aggregated supramolecules, to affect their photophysics through the excitonic interaction dependent on geometries of the chlorin macrocycles.
{"title":"Self-aggregation of synthetic 7- or 8-unsubstituted bacteriochlorophyll-d analogs","authors":"Kengo Nakakuki , Shin-ichi Sasaki , Hitoshi Tamiaki","doi":"10.1016/j.jphotochem.2024.116257","DOIUrl":"10.1016/j.jphotochem.2024.116257","url":null,"abstract":"<div><div>Zinc methyl 3<sup>1</sup>-demethyl-bacteriopheophorbides-<em>d</em> lacking the 7-methyl or 8-ethyl group were prepared from chlorophyll-<em>b</em> or <em>a</em>, respectively, via Pinnick oxidation of a formyl to carboxy group at the 7- or 8-position followed by its pyrolysis. The substitution effects of the 7-methyl and 8-ethyl groups on the optical properties of the zinc chlorophyll derivatives in THF and in an aqueous Triton X-100 micellar solution were investigated. In tetrahydrofuran (THF), all the synthetic zinc complexes were monomeric to give sharp electronic absorption bands and highly fluorescent emission bands. The Qy absorption and fluorescence emission maxima were hypsochromically shifted in the order of zinc 7-methyl-8-ethyl-, 7-methyl-8-deethyl-, and 7-demethyl-8-ethyl-chlorins, but no significant effects of the 7- or 8-dealkylation were observed in the Qx and Soret bands. In the aqueous micelles, the three zinc 3-hydroxymethyl-13<sup>1</sup>-oxo-chlorins self-aggregated to give broadened and red-shifted absorption bands, which were similar as in the self-aggregates of bacteriochlorophylls-<em>c</em>/<em>d</em>/<em>e</em> in the major light-harvesting antennas of green photosynthetic bacteria (chlorosomes). The dealkylation moved the red-shifted Qy maxima of the self-aggregates to shorter wavelengths than that of the alkylated compound. The substitution effect was comparable to the bathochromic shifts in the Qy bands of the bacteriochlorophyll self-aggregates in chlorosomes by the sequential methylation at the 8-ethyl terminal. The dealkylation slightly suppressed the self-aggregation ability, revealing the CH–π interaction of the alkyl groups with the chlorin chromophore in the self-aggregated supramolecules, to affect their photophysics through the excitonic interaction dependent on geometries of the chlorin macrocycles.</div></div>","PeriodicalId":16782,"journal":{"name":"Journal of Photochemistry and Photobiology A-chemistry","volume":"462 ","pages":"Article 116257"},"PeriodicalIF":4.1,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Following our previous report on the heat trapping in organic/inorganic hybrid compound with bilayer structure formed by cationic polyfluorinated surfactant containing azobenzene moiety (C3F-Azo-C6H) in the interlayer of cation-exchangeable synthetic clay (Smecton SA: SSA) nanosheets having been probed by a temperature sensing Rhodamine B (RhB) upon excitation by a fixed wavelength of visible light, a systematic study of the effect of wavelength dependency for the excitation was carried out to get deeper insight into the heat trapping. Evident wavelength effect of excitation on the temperature elevation was observed. Among three components in the fluorescence lifetime (τ1, τ2, τ3) of RhB, the local temperatures T1, T2 deduced from τ1, τ2 exhibited a systematic temperature elevation upon excitation of RhB with a shorter wavelength of visible light (570–520 nm). Estimation of the energy stored against the energy input indicated that an excess energy initially deposited at Franck-Condon state is retained in a limited number of local modes during the fluorescence lifetime through a pretty slow intramolecular vibrational relaxation (IVR) in the interlayer. Structural analysis by TD-DFT calculation strongly suggested that all the local modes within RhB are classified into four groups (I–IV), which well coincides with the prediction by a comparison analysis in respect to the energy stored against the energy input to rationalize that the IVR of RhB for τ1 component (T1) in the interlayer is limited among the local mode groups I (#1–10)–II (#11–21) and τ2 component (T2) being restricted up to group III (# 22–36). The systematic study revealed that the hybrid compound C3F-Azo-C6H/SSA provides a unique microenvironment having gaseous/vacuum-like atmosphere to a molecule incorporated in the narrow gap space sandwiched by neighboring C3F-Azo-C6H molecules in the interlayer to allow an inherently slow IVR.
{"title":"Heat trapping with restricted energy dissipation in polyfluorinated supra molecular environment: Wavelength dependency of energy deposition","authors":"Yu Nabetani , Vivek Ramakrishnan , Ryosuke Nakazato , Yuki Iwata , Hiroshi Tachibana , Haruo Inoue , Tsutomu Shiragami","doi":"10.1016/j.jphotochem.2024.116245","DOIUrl":"10.1016/j.jphotochem.2024.116245","url":null,"abstract":"<div><div>Following our previous report on the heat trapping in organic/inorganic hybrid compound with bilayer structure formed by cationic polyfluorinated surfactant containing azobenzene moiety (C3F-Azo-C6H) in the interlayer of cation-exchangeable synthetic clay (Smecton SA: SSA) nanosheets having been probed by a temperature sensing Rhodamine B (RhB) upon excitation by a fixed wavelength of visible light, a systematic study of the effect of wavelength dependency for the excitation was carried out to get deeper insight into the heat trapping. Evident wavelength effect of excitation on the temperature elevation was observed. Among three components in the fluorescence lifetime (τ<sub>1</sub>, τ<sub>2</sub>, τ<sub>3</sub>) of RhB, the local temperatures <em>T</em><sub>1</sub>, <em>T</em><sub>2</sub> deduced from τ<sub>1</sub>, τ<sub>2</sub> exhibited a systematic temperature elevation upon excitation of RhB with a shorter wavelength of visible light (570–520 nm). Estimation of the energy stored against the energy input indicated that an excess energy initially deposited at Franck-Condon state is retained in a limited number of local modes during the fluorescence lifetime through a pretty slow intramolecular vibrational relaxation (IVR) in the interlayer. Structural analysis by TD-DFT calculation strongly suggested that all the local modes within RhB are classified into four groups (I–IV), which well coincides with the prediction by a comparison analysis in respect to the energy stored against the energy input to rationalize that the IVR of RhB for τ<sub>1</sub> component (<em>T</em><sub>1</sub>) in the interlayer is limited among the local mode groups I (#1–10)–II (#11–21) and τ<sub>2</sub> component (<em>T</em><sub>2</sub>) being restricted up to group III (# 22–36). The systematic study revealed that the hybrid compound C3F-Azo-C6H/SSA provides a unique microenvironment having gaseous/vacuum-like atmosphere to a molecule incorporated in the narrow gap space sandwiched by neighboring C3F-Azo-C6H molecules in the interlayer to allow an inherently slow IVR.</div></div>","PeriodicalId":16782,"journal":{"name":"Journal of Photochemistry and Photobiology A-chemistry","volume":"462 ","pages":"Article 116245"},"PeriodicalIF":4.1,"publicationDate":"2024-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-27DOI: 10.1016/j.jphotochem.2024.116248
Sichen Zhang , Yu Fang , Jie Wang , Aobo Sun , Jiale Li , Xue Zhang , Chunfei Wang , Lutan Zhou , Lei Hu , Hui Wang
Lipid droplets (LDs), as an important organelle, play a crucial role in regulating cell metabolism and growth. When their function is disrupted, they may lead to a series of diseases, which makes the monitoring of LDs the focus of researchers. In this study, relying on the lipophilic properties of triphenylamine and using its derivatives as targeting groups, we developed a series of BODIPY-based fluorescent probes (X1-X5) based on NBO structure. Probes X1, X2, and X4 all exhibited good aggregation-induced emission (AIE) performance. In addition, these probes have excellent photostability and low cytotoxicity, and have a large stokes shift (>100 nm) in H2O. Especially, probe X4 has been successfully applied to living cell LDs imaging, providing valuable tools for the field of biological imaging.
{"title":"Triphenylamine-based AIE fluorescence probe for lipid droplets imaging in living cells","authors":"Sichen Zhang , Yu Fang , Jie Wang , Aobo Sun , Jiale Li , Xue Zhang , Chunfei Wang , Lutan Zhou , Lei Hu , Hui Wang","doi":"10.1016/j.jphotochem.2024.116248","DOIUrl":"10.1016/j.jphotochem.2024.116248","url":null,"abstract":"<div><div>Lipid droplets (LDs), as an important organelle, play a crucial role in regulating cell metabolism and growth. When their function is disrupted, they may lead to a series of diseases, which makes the monitoring of LDs the focus of researchers. In this study, relying on the lipophilic properties of triphenylamine and using its derivatives as targeting groups, we developed a series of BODIPY-based fluorescent probes (<strong>X1</strong>-<strong>X5</strong>) based on NBO structure. Probes <strong>X1</strong>, <strong>X2</strong>, and <strong>X4</strong> all exhibited good aggregation-induced emission (AIE) performance. In addition, these probes have excellent photostability and low cytotoxicity, and have a large stokes shift (>100 nm) in H<sub>2</sub>O. Especially, probe <strong>X4</strong> has been successfully applied to living cell LDs imaging, providing valuable tools for the field of biological imaging.</div></div>","PeriodicalId":16782,"journal":{"name":"Journal of Photochemistry and Photobiology A-chemistry","volume":"462 ","pages":"Article 116248"},"PeriodicalIF":4.1,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-27DOI: 10.1016/j.jphotochem.2024.116249
Geethanjali Anand , Mintu Porel
Förster resonance energy transfer (FRET) is a powerful technique for investigating molecular interactions at close ranges. Identifying the optimal donor–acceptor pair is crucial for maximizing energy transfer efficiency, significantly improving sensitivity and accuracy in measurements. In this study, a library of six functionally tunable dansyl-tagged molecules (C1-C6) was designed, synthesized, and characterized using 1H NMR, 13C NMR, and LC-MS techniques to serve as potential donor fluorophores in FRET with the acceptor drug rifampicin (RF). The synthetic strategy aimed to incorporate two distinct tunable centers, allowing for the introduction of cyclic, aromatic, and aliphatic substituents into the molecular skeleton. The potential of C1-C6 to participate in FRET was evaluated through spectral overlap assessment, steady-state fluorescence measurements, and lifetime analysis. The impact of varying functional substituents on FRET was investigated through FRET efficiency, donor–acceptor distances, and energy transfer rates. Among the synthesized molecules, C1 with both substituents as benzyl groups, exhibited the highest FRET efficiency of 87 ± 1.03 % and the shortest donor–acceptor distance of 2.2 nm, in contrast C6 containing a cyclohexyl group on one end and a benzyl group on the other, showed the lowest FRET efficiency of 51 ± 0.53 %. The feasibility of FRET was validated by analyzing the energy levels of the Frontier Molecular Orbitals (FMOs) of the donor molecules and rifampicin using Density Functional Theory (DFT). A reduction in the HOMO-LUMO gap observed in C1 after interacting with RF further confirmed their interaction, indicating stabilization of the FMOs.
{"title":"Tuning Förster Resonance Energy Transfer Efficiency via Functional Group Modulation of Dansyl-Tagged Molecules in Interaction with The Anti-tuberculosis Drug, Rifampicin","authors":"Geethanjali Anand , Mintu Porel","doi":"10.1016/j.jphotochem.2024.116249","DOIUrl":"10.1016/j.jphotochem.2024.116249","url":null,"abstract":"<div><div>Förster resonance energy transfer (FRET) is a powerful technique for investigating molecular interactions at close ranges. Identifying the optimal donor–acceptor pair is crucial for maximizing energy transfer efficiency, significantly improving sensitivity and accuracy in measurements. In this study, a library of six functionally tunable dansyl-tagged molecules (<strong>C1-C6</strong>) was designed, synthesized, and characterized using <sup>1</sup>H NMR, <sup>13</sup>C NMR, and LC-MS techniques to serve as potential donor fluorophores in FRET with the acceptor drug rifampicin (RF). The synthetic strategy aimed to incorporate two distinct tunable centers, allowing for the introduction of cyclic, aromatic, and aliphatic substituents into the molecular skeleton. The potential of <strong>C1-C6</strong> to participate in FRET was evaluated through spectral overlap assessment, steady-state fluorescence measurements, and lifetime analysis. The impact of varying functional substituents on FRET was investigated through FRET efficiency, donor–acceptor distances, and energy transfer rates. Among the synthesized molecules, <strong>C1</strong> with both substituents as benzyl groups, exhibited the highest FRET efficiency of 87 ± 1.03 % and the shortest donor–acceptor distance of 2.2 nm, in contrast <strong>C6</strong> containing a cyclohexyl group on one end and a benzyl group on the other, showed the lowest FRET efficiency of 51 ± 0.53 %. The feasibility of FRET was validated by analyzing the energy levels of the Frontier Molecular Orbitals (FMOs) of the donor molecules and rifampicin using Density Functional Theory (DFT). A reduction in the HOMO-LUMO gap observed in <strong>C1</strong> after interacting with RF further confirmed their interaction, indicating stabilization of the FMOs.</div></div>","PeriodicalId":16782,"journal":{"name":"Journal of Photochemistry and Photobiology A-chemistry","volume":"462 ","pages":"Article 116249"},"PeriodicalIF":4.1,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143166562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号