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Photo-controllable antifouling hydrogels embedded with AgNPs coated spiropyran functionalized mesoporous silica for long-term antibacterial activity

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Nano Research 2024年第9期17卷 8337-8349页

作者： Wei Su Fei Wang Bing Chen Ruoke Li Jindian Liu Junjie Xu Jianhua Fan Yueling Liu State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai 200237China Department of Applied Biology School of BiotechnologyEast China University of Science and TechnologyShanghai 200237China

Silver nanoparticles(AgNPs)are widely used in antimicrobial ***,its easy aggregation and rapid loss hinder the effective *** address this issue,a novel stimuli-responsive antibacterial nanocomposite(Ag@SP-MSN)was developed based on spiropyran covalently conjugated mesoporous silica nanoparticles(284.6 nm)and AgNPs(27.1 nm)via strong electrostatic *** transmission electron microscopy(TEM)and atomic force microscopy(AFM)images proved the successful modification of AgNPs onto *** light-induced maximum loading amount towards AgNPs was calculated to be 95.0 wt.%after ultraviolet irradiation,while the amount of AgNPs released from Ag@SP-MSN was 94.4 wt.%under visible light in the aid of ammonia(0.1%,v/v).Upon cycled light irradiation,Ag@SP-MSN could recover 84.5 wt.%of AgNPs even after four *** proposed Ag@SP-MSN exhibited better antibacterial activity against both *** and *** than Ag@MSN under visible light illumination,indicating the efficient photo-responsive isomerization of ***,the Ag@SP-MSN embedded gel demonstrated outstanding antifouling ability even after 21 days when compared to AgNPs *** long-term photo-controllable antifouling property proved the excellent reversible absorption and release of Ag@SP-MSN towards *** work provides new insights into the safe utilization of nanomaterials,offering promising advancements to meet clinical antibacterial requirements.

关键词： light-responsive silver nanoparticles spiropyran mesoporous silica nanoparticles antibacterial activity

Dual sensitivity of spiropyran-functionalized carbon dots for full color conversions

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Science China Chemistry 2022年第11期65卷 2274-2282页

作者： Lin Ai Huimin Liu Rui Liu Haoqiang Song Ziqi Song Mingjun Nie Geoffrey I.N.Waterhouse Siyu Lu Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450000China College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China School of Chemical Sciences The University of AucklandAuckland 142New Zealand

Multicolor phosphors that respond rapidly to external stimuli are highly desirable for many applications, including lighting,optical displays and sensors. Herein, spiropyran(SP)-functionalized carbon dots(CDs) were synthesized with a broad-spectrum output that were responsive to both ultraviolet(UV)/visible light and pH. The SP-CDs possessed strong ester linkages between the UV-absorbing/blue-emitting CDs and blue-absorbing/red-emitting surface SP groups, allowing efficient F?rster resonance energy transfer(FRET) between the donor and acceptor. UV irradiation or acid addition cause the SP ring opening to merocyanine(MC) or protonated MCH+forms, respectively, together with the formation of sheet-like aggregates. These processes enhanced the red emissions by the SP groups and attenuated blue emissions from the CDs. These changes were fully reversible under visible light or basic conditions, respectively, allowing dynamic regulation of the fluorescence properties(emission colors from blue to red, photoluminescence(PL) intensity) under photoirradiation on the timescale of minutes. As proof-of concept, we demonstrate that the emission properties of the SP-CDs can be used to construct UV and pH sensing materials as well as light emitting diode(LED) with different colors.

关键词： carbon dots dual-sensitivity full color emission spiropyran F?rster resonance energy transfer

UV-induced self-assembly of the inclusion complexes formed between a long-chain photochromic spiropyran and cyclodextrins

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Science China Chemistry 1999年第2期42卷 113-120页

作者：隋强周金渭何炜李仲杰王艳乔 Institute of Chemistry Chinese Academy of Sciences Beijing China Department of Chemistry Northwest University Xi’an China

Photochromic spiropyran with a long chain alkyl substitute can form axial complexes with α-, β-, and γ-cyclodextrin, respeetively. The complexes show normal photochromism. The novel property of the colored forms of the inclusion complexes is that they can assemble into dimers at relatively low concentration or J-aggregates at relatively high concentration. For α-, β-, and γ-cyclodextrin, λmax of the J-aggregates appear at 700 650, and 630 nm, respectively. The sizes of the cavities of cyclodextrins have very little effect on the spectra and decoloration kinetics of the dimers, but have great effects on the spectra of the J-aggregates. Unlike the charge transfer complex of Krongauz, the decoloration process of the dimers or J-aggregates cannot be described by an exponential or a two-exponential kinetics, but obey half-order kinetics very well. Another result that can be deduced from the kinetic analysis is that unlike the dimers formed in apolar solvents or in polymers, which consist of a colored molecule (B’) and a colorless molecule (á) with a composition of A’B’, in the present system, the dimer of the inclusion complex consists of two colored molecules (B). All these results can be interpreted by the proposed structure model and decoloration mechanism.

关键词： UV-induced self-assembly photochromism spiropyran cyclodextrin inclusion complex.

Switchable near-infrared photoluminescence of PbS quantum dots through light and heat modulated hole transfer to spiropyran molecules

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Nano Research 2024年第12期17卷 10483-10489页

作者： Zongwei Chen Zhengxiao Li Fan Li Jingzhu Huo Xinyi Meng Shihao Ma Wenbo Zhu Fengqi Guo Jia-Hua Hu Kaifeng Wu Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou 450052China College of Chemistry Zhengzhou UniversityZhengzhou 450052China State Key Laboratory of Molecular Reaction Dynamics and Collaborative Innovation Center of Chemistry for Energy Materials(iChEM) Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Precise modulation of photoluminescence(PL)of nanomaterials by external control is of great interest in such diverse areas as photocatalysis,memory and *** studies have combined colloidal quantum dots(QDs)with photochromic molecules to construct optically switchable PL ***,it still remains challenging to switch the PL on and off in the near-infrared(NIR)region with multi-stimuli such as light and ***,we present light and heat triggered modulation of the NIR PL of PbS QDs using adjacent spiropyran *** NIR PL of PbS was reversibly switched on and off through the isomerization process of spiropyran molecules that can be triggered by either light irradiation or *** PL intensity of the off state is low enough to yield an on/off ratio as high as *** absorption measurements revealed ultrafast photoinduced hole transfer from PbS to spiropyran,the rate and efficiency of which depend critically on the driving force that can be deeply modulated through spiropyran *** study not only establishes a novel multi-stimuli switchable PL system in the NIR,but also provides fundamental guidelines for the design for such systems for a variety of emerging applications.

关键词： photoswitch near-infrared(NIR)photoluminescence quantum dots spiropyran hole transfer

Synthesis of novel chalcone derivatives and their stabilization effect of spiropyran in PMMA films

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Chinese Chemical Letters 2011年第9期22卷 1025-1028页

作者： Zheng Kai Si Qing Zhang Min Zhao Xue Yuan Yuan Zhu Liang Ming Qiao Rong Sheng Yan Gang Liu School of Chemistry and Chemical Engineering Shanghai Jiaotong University Shanghai 200240 China

Three novel bis-chalcone derivatives with different alkyldioxy spacers were synthesized and dispersed into polymethyl methacrylate （PMMA） chloroform solution with 6-nitro-1＇-ethyl-3＇,3＇-dimethylspiro-2H-1-benzopyran-2,U-indoline （ESP） to prepare photochromic PMMA films in a facile way. After irradiation with 365 nm UV light, the photocrosslinking reaction between chalcone units was proved to retard the decolorization of merocyanine form of the photochromic spiropyran effectively, as results of the steric hindrance produced by photocycloaddition of chalcone groups. It has been found that the bis-chalcone molecule with the shortest spacer has the most effective stabilizing effect on retardation of decoloration of spiropyran. reserved.

关键词： Photochromism Chalcone spiropyran Photocycloaddition Slabilization effect

Spectral Properties and Photochromic Characteristics of spiropyran Dyes

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Chemical Research in Chinese Universities 2006年第4期22卷 505-509页

作者： SHEN Kai-hua HAN Jian-guo ZHANG Gang CHOI Dong-hoon The State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 P. R. China The Key Laboratory of Cellulose and Lignocellulosics Chemistry Guangzhou Institute of Chemistry Chinese Academy of Sciences Guangzhou 510650 P. R. China Polymer and Fiber Material Engineering Kyunghee University Kyong Kido 449-701 Korea

A bis-benzospiropyran（BBSP） and nitro-substituted indoline spirobenzopyrans（SBP） were prepared by following a simple procedure. The reaction mechanism of synthesizing bis-benzospiropyran is discussed. A comparative analysis of the spectral and photochromic properties between SBP and BBSP was carried out with the aid of a PMMA film. The results indicate that chemical structures and UV irradiation played an important role in the spectral and photochromic properties of SBP and BBSP, which would readily affect λmax of the colored forms and the reversibility. The IR spectra and ^1H NMR spectra of these compounds are used to interpret the photochromic phenomena under different UV irradiation and determine the configurations of SBP and BBSP.

关键词： Photochromism spiropyran UV radiation Protonation

Structure and photochromism of spiropyran assemblies

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Science China Chemistry 1995年第3期38卷 288-295页

作者：杜祖亮赵伟利马晓东朱自强明阳福樊美公吕安德 Surface Science Laboratory Henan University Kaifeng 475001 China Institute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101 China Changchun Institute of Physics Chinese Academy of Sciences Changchun 130021 China

Nanocluster assemblies of spiropyran compounds have been prepared by means of LB technique, and the relations between the subphase, pH value, condition of preparation and the structure of the fabricated LB film are systematically investigated. The stability, photochromic fatigue properties of the spiropyran LB film, which are of primary importance in optic signal storage applications, are also studied in detail. A kind of supermolecular film with homogeneously distributed J aggregates of similar granular size has been obtained with the optical resolution in the order of micrometer. Finally, a nondestructive readout method for such an LB film to be used as the optic signal storage film is proposed.

关键词： spiropyran photochromism LB technique signal storage J aggregates.

A Multiresponsive Hydrophobic Associating Hydrogel Based on Azobenzene and spiropyran

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Chinese Journal of Chemistry 2019年第8期37卷 793-798页

作者： Anqi Liu Chenxiao Xiong Xiaoying Ma Wenjing Ma Ruyi Sun School of Chemistry and Molecular Engineering East China Normal University500 Dongchuan RoadShanghai 200241China

Summary of main observation and conclusion Stimuli-responsive hydrogels crosslinked by weak noncovalent bonds such as hydrogen bonds,ionic interactions,host-guest interactions and hydrophobic interactions have been extensively ***,azobenzene and spiropyran acting as two hydrophobic pendant groups were introduced into a hydrophilic polyacrylamide (PAM) via free radical copolymerization to construct a hydrophobic interaction based thermo-,light-responsive polymer *** viscosity and color could be reversibly regulated by heating and ***,its color could be specifically switched by light without obvious viscosity *** gel was also capable of being transited to sol by addition of β-cyclodextrin (β-CD),which encaged the hydrophobic groups and then increased the solubility of polymer in *** hydrogel could be regained after UV irradiation at λ=365 nm,and after irradiation at λ=440 nm,the hydrogel changed into a clear sol again.

关键词： polyacrylamide (PAM) Azobenzene spiropyran

Light-Triggered Molecular Level Self-Healing spiropyran Thin Film

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Chinese Journal of Chemistry 2013年第12期31卷 1483-1487页

作者： Bingjie Yang Juehuan Liu Hongzhi Zheng Sean Xiao-An Zhang State Key Laboratory of Supramolecular Structure and Materials College of Chemistry Jilin University Changchun Jilin 130012 China

spiropyran thin film with capability of light-triggered molecular level sell-healing has been successtully aesigned and fabricated by Langmuir-Blodgett technology. Various remarkable properties of thin film shrinkage or height increase or self-healing nano-defect recovery under different fabrication conditions have been observed. In addition, further evidence of the self-healing, which resulted from the movement of spiropyran molecules （such as ＂standing＂＂lie-down＂ and ＂tip-toes＂ etc.） on the substrate, has also been observed from the reversible contact angle change of the thin film.

关键词： spiropyran Langmuir-Blodgett self-healing molecular movement contact angle