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Light(Science & Applications) 2022年第11期11卷 2564-2566页

作者： Sophie Brasselet Aix Marseille Univ CNRSCentrale MarseilleInstitut FresnelF-13013 MarseilleFrance

Combining polarization modulation Fourier analysis and spatial information in a joint reconstruction algorithm for polarization-resolved fluorescence imaging provides not only a gain in spatial resolution but also a s... 详细信息

关键词： polarization resolution fluorescence

fluorescence emission modulation in cyanido-bridged Fe(Ⅱ)spin crossover coordination polymers

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Science China Chemistry 2022年第8期65卷 1569-1576页

作者： Xue-Ru Wu Zhi-Kun Liu Min Zeng Ming-Xing Chen Jun Tao Shu-Qi Wu Hui-Zhong Kou Department of Chemistry Tsinghua UniversityBeijing 100084China Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringLiangxiang CampusBeijing Institute of TechnologyBeijing 102488China Analytical Instrumentation Center College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Institute for Materials Chemistry and Engineering&IRCCS Kyushu University744 MotookaNishi-kuFukuoka 819-0395Japan

Synergistic fluorescent spin crossover(SCO)bifunctional molecular materials have novel applications in the molecule-based magneto-optical switches.Herein,we report two novel three-dimensional(3D)Hofmann-type fluorescent SCO complexes[Fe^(II)-(tppe)MI(CN)_(2)]ClO_(4)·nSolv(tppe=tetra-(4-pyridylphenyl)ethene,M=Ag(tppe-Ag),Au(tppe-Au)).Both complexes show one-step abrupt SCO with the transition temperature of 230 K for tppe-Ag,and 245 K for tppe-Au accompanied by a color change from red to light yellow.The SCO process is confirmed by the variable-temperature single-crystal X-ray diffraction analysis on tppe-Ag.For the first time,the abnormal increase in emission intensity and concomitant large bathochromic shifts in the fluorescence spectra during the SCO process are realized in the 3D Hofmann-type coordination polymers expanded by the tetradentate tppe ligand.Moreover,tppe-Ag exhibits the unprecedented fluorescence emission from green to the edge of yellow.

关键词： fluorescence spin crossover multifunctional materials coordination polymers synergetic effect

fluorescence detection of phosphate in an aqueous environment by an aluminum-based metal-organic framework with amido functionalized ligands

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Frontiers of Environmental Science & Engineering 2022年第12期16卷 111-120页

作者： Peng Li Lingqian Dong Han Jin Jingren Yang Yonghui Tu Chao Wang Yiliang He School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai200240China China-UK Low Carbon College Shanghai Jiao Tong UniversityShanghai200240China Department of Instrument Science and Engineering School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai200240China

The on-site monitoring of phosphate is important for environmental management.Conventional phosphate detection methods are not appropriate to on-site monitoring owing to the use of complicated detection procedures,and the consequent high cost and maintenance requirements of the detection apparatus.Here,a highly sensitive fluorescence-based method for phosphate detection with a wide detection range was developed based on a luminescent aluminum-based metal-organic framework(Al-MOF).The Al-MOF was prepared by introducing amine functional groups to conventional MIL to enhance phosphate binding,and exhibited excellent fluorescence properties that originated from the ligand-to-metal charge transfer(LMCT).The detection limit was as low as 3.25µmol/L(0.10 mg/L)and the detection range was as wide as 3–350µmol/L(0.10–10.85 mg/L).Moreover,Al-MOF displayed specific recognition toward phosphate over most anions and metal cations,even for a high concentration of the co-existent ions.The mechanism of phosphate detection was analyzed through the characterization of the combination of Al-MOF and phosphate,and the results indicated the high affinity between Al-O and phosphate inhibited that the LMCT process and recovered the intrinsic fluorescence of NH2−H2BDC.The recovery of the developed detection method reached a satisfactory range of 85.1%–111.0%,and the feasibility of on-site phosphate detection was verified using a prototype sensor for tap water and lake water samples.It was demonstrated that the prepared Al-MOF is highly promising for on-site detection of phosphate in an aqueous environment.

关键词： fluorescence Metal-organic framework Phosphate Detection Al-MOF

fluorescence of Single Conjugated Chains of MEH-PPV Dispersed in Polymer Matrix: What Do We See in the Microscope?

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Chinese Journal of Chemistry 2023年第19期41卷 2536-2544页

作者： Mingyi Xie Marina V.Kuzimenkova Per-Olof Larsson Yuxi Tian Ivan G.Scheblykin Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210023 China Chemical Physics and NanoLund Lund UniversityPO Box 124SE-22100 LundSweden Pure and Applied Biochemistry Lund UniversityPO Box 124SE-22100 LundSweden

It has been a mystery that the detected fluorescence intensity of single MEH-PPV molecules is much lower than expected based on their chain length.In this review,after re-evaluating of the literature data in the light of new specially designed experiments,we present a comprehensive explanation of this issue:The actual size of MEH-PPV molecules at single molecule level is much smaller than expected due to de-aggregation and chain scission,while static quenching("dark matter")also exists for large molecules,further reducing their brightness.

关键词： MEH-PPV Single molecule spectroscopy Brightness fluorescence Molecular weight anrohonci

fluorescence detection of perfluorooctane sulfonate in water employing a tetraphenylethylene-derived dual macrocycle Bowtie Cyclophane

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Chinese Chemical Letters 2022年第3期33卷 1493-1496页

作者： Sheng-Nan Lei Huan Cong Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and Chemistry&School of Future TechnologyUniversity of Chinese Academy of SciencesChinese Academy of SciencesBeijing 100190China

Because the widely used perfluorooctane sulfonate(PFOS) is harmful to both environment and human health, it is of great significance and urgency to develop sensitive and selective sensors for the detection of trace PFOS in water. In this study, a tetraphenylethylene-derived macrocycle Bowtie Cyclophane has been developed as a fluorescent sensor based on aggregation-induced emission enhancement and fluorochromism. Sensitive detection of PFOS has been achieved with a limit of detection(LOD) of47.3 ± 2.0 nmol/L(25.4 ± 1.1 μg/L) accompanied by visual fluorescence color changes.

关键词： fluorescence Aggregation Perfluorooctane sulfonate Tetraphenylethylene Macrocycle

fluorescence-based quantitative characterization of structural phase transitions in Li^(+)/Er^(3+):BaTiO_(3)ferroelectric ceramics

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Journal of Materials Science & Technology 2021年第33期92卷 143-147页

作者： Jiaming Li Enwei Sun Yaping Ma Huashan Zheng Hua Zhao Zhiguo Zhang School of Physics Harbin Institute of TechnologyHarbin 150001China Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China School of Materials and Engineering Harbin Institute of TechnologyHarbin 150001China

We propose a method to quantitatively characterize the fine phase transition processes of Li^(+)/Er^(3+):BaTiO_(3)(BLET)ferroelectric materials by observing fluorescence wavelength shift.A lithium and erbium co-doped barium titanate ferroelectric ceramic was fabricated and the down-conversion infrared fluorescence spectra of the transition^(4)I13/2→^(4)I15/2 were measured as a function of temperature.The three structural phase transition processes,namely rhombohedral-orthorhombic,orthorhombic-tetragonal,and tetragonal-cubic transformations,determined by X-ray diffraction results are accompanied by corresponding changes in the position of the fluorescence peaks,yielding an exact consistency.This contactless,non-destructive and spatially-resolved fluorescence method provides a localized quantitative analysis for the phase transition processes of BLET ceramics.As this method is based on the fluorescence peak wavelength dependence on the crystal environment,it may potentially be used to characterize the phase transitions in other ferroelectric materials.

关键词： Ferroelectrics Phase transition fluorescence X-ray diffraction

fluorescence microscope light source based on integrated LED

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Light(Science & Applications) 2023年第10期12卷 1990-1991页

作者： Jianchen Zi Hai Bi Jihua Laboratory No.28 Huandao South RoadNanhai district528200FoshanChina

An LED-integrated excitation cube(LEC)was designed to address the limitations of conventional fluorescence lamps.The LEC has a decentralized structure,high optical power density,and efficient illumination.The optical efficiency of LECs is 1–2 orders of magnitude higher than that of mercury lamps,enabling high-quality fluorescence imaging with spectral coverage from UV to red.LECs can be easily installed on commercial fluorescence microscopes by replacing conventional fluorescence filter cubes,and a built-in LEC driver can identify the types of LEDs in different spectral bands to adopt optimal operating conditions.

关键词： fluorescence illumination mercury

fluorescence cholangiography enhances surgical residents’ biliary delineation skill for laparoscopic cholecystectomies

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World Journal of Gastrointestinal Surgery 2020年第3期12卷 93-103页

作者： Narongsak Rungsakulkij Siraprapa Thewmorakot Wikran Suragul Watoo Vassanasiri Pongsatorn Tangtawee Paramin Muangkaew Somkit Mingphruedhi Suraida Aeesoa Department of Surgery Faculty of Medicine Ramathibodi Hospital Mahidol University

BACKGROUND Laparoscopic cholecystectomy(LC)is a minimally invasive procedure,often performed by surgical residents(SRs).fluorescence cholangiography(FC)enables real-time identification of biliary anatomy.AIM To investigate the benefit of FC for enhancing SRs’identification skills.METHODS Prospective data was collected from January 2018 to June 2018 at our hospital.The study cohorts were the SRs(study group,n=15)and the surgical staff(SS;control group,n=9).Participants were assigned to watch videos of LCs with FC from five different patients who had gallbladder disease,and identify structures in the video clips(including cystic duct,common bile duct,common hepatic duct,and cystic artery),first without FC,and then with FC.RESULTS In the without-FC phase,the overall misidentification rate by SRs(21.7%)was greater than that of the SS(11.8%;P=0.018),However,in the FC phase,the two groups did not significantly differ in misidentification rates(23.3%vs 23.3%,P=0.99).Paired-structure analysis of the without-FC and with-FC phases for the SR group found a significantly higher misidentification rate in the without-FC phase than the with-FC phase(21.9%vs 10.9%;P<0.01).However,misidentification rates in the with-FC phase did not significantly differ between SRs and SS.CONCLUSION FC enhanced identification skills of inexperienced surgeons during LC compared with conventional training.Combined with simulation-based video training,FC is a promising tool for enhancing technical and decision skills of trainees and inexperienced surgeons.

关键词： Laparoscopic cholecystectomy fluorescence Cholangiography Residency Education

fluorescence Signal Amplification Strategies Based on DNA Nanotechnology for miRNA Detection

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Chemical Research in Chinese Universities 2020年第2期36卷 194-202页

作者： LI Tao DUAN Ruilin DU AN Zhijuan HUANG Fujian XIA Fan Engineering Research Center ofNano-geomaterials Ministry of EducationFaculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430074R R.China

In this review,the most recent progresses in the field of fluorescence signal amplification strategies based on DNA nanotechnology for miRNA are summarized.The types of signal amplification are given and the principles of amplification strategies are explained,including rolling circle amplification(RCA),catalytic hairpin assembly(CHA),hybridization chain reaction(HCR)and DNA walker.Subsequently,the application of these signal amplification methods in biosensing and bioimaging are covered and described.Finally,the challenges and the outlook of fluorescence signal amplification methods for miRNA detection are briefly commented.

关键词： Signal amplification DNA nanotechnology fluorescence miRNA detection Biosensing and bioimaging

Cucurbit[8]uril-mediated multi-color fluorescence system for time-dependent information encryption

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Science China Chemistry 2023年第4期66卷 1111-1119页

作者： Biyan Lin Qian Wang Zhen Qi Hanren Xu Da-Hui Qu Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterInstitute of Fine ChemicalsFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Programming microscopic assembly mode to control macroscopic property is an attractive research objective.In particular,controlling molecular assembly to control fluorescence is of considerable interest for developing smart fluorescent materials.Herein,a color-tunable supramolecular emissive system was developed based on cucurbit[8]uril mediated host-guest assembly.Chemical designing for the molecular structures with minimized change resulted in different assembly modes and hence generating distinctive fluorescence,including green,yellow and orange with the addition of cucurbit[n]uril.Taking advantage of this feature,the advanced information encryption material(4D code)with multiple encryption levels and time-dependent encryption feature was developed.Such a code was dynamic on time scale,generating a series of 3D codes with time.The encrypted information only can be recognized by integrating time-coursed codes.This work provides a new insight for designing intelligent fluorescent materials for information encryption with high level of security.

关键词： host-guest systems fluorescence multi-color emission information encryption cucurbituril