Updated on 2026/03/10

写真a

 
SAGARA YOSHIMITSU
 
Organization
School of Materials and Chemical Technology Associate Professor
Title
Associate Professor
Profile

Yoshimitsu Sagara is an Associate Professor working on supramolecular materials at Department of Materials Science and Engineering in Tokyo Institute of Technology. He was born in 1981 in Takaoka city. He received his Ph.D. with Prof. Takashi Kato from the University of Tokyo in 2009. After working as a JSPS postdoctoral fellow in Kato’s group for one year, he joined Prof. Tetsuo Nagano’s group as a JSPS postdoctoral fellow in the University of Tokyo. Then, he joined Prof. Christoph Weder’s group as a JSPS Postdoctoral Fellow for Research Abroad in 2013. After that, he started to work at Research Institute for Electronic Science (RIES) in Hokkaido University in 2015. He was appointed the present position in 2020. His research interests include various stimuli-responsive photofunctional materials based on supramolecular materials including liquid crystals, micelles, gels, and polymers and their practical applications. Especially, he is now focusing on a varitey of mechanoresponsive luminescent materials.

External link

News & Topics

Degree

  • Ph.D ( 2009.3   The University of Tokyo )

Research Interests

  • supramolecular mechanophore

  • cyclophane

  • mechanophore

  • rotaxane

  • fluorescence

  • molecular assembly

  • mechanoresponsive luminescent materials

  • liquid crystals

  • Elastomer

  • Low-dimensional Mechanochromic Luminescent Materials

Research Areas

  • Nanotechnology/Materials / Functional solid state chemistry

  • Nanotechnology/Materials / Bio chemistry

  • Nanotechnology/Materials / Polymer materials

  • Nanotechnology/Materials / Organic functional materials

Education

  • the University of Tokyo   School of Engeering   Department of Chemistry and Biotechnology

    2004.4 - 2009.3

      More details

  • The University of Tokyo   School of Engineering   Department of Chemistry and Biotechnology

    2002.4 - 2004.3

      More details

  • The University of Tokyo   College of Arts and Sciences

    2000.4 - 2002.3

      More details

Research History

  • JST 創発研究者

    2021.4

      More details

  • Institute of Science Tokyo   School of Materials and Chemical Technology   Associate Professor

    2020.4

      More details

    Country:Japan

    researchmap

  • JST   PRESTO researcher

    2017.10 - 2021.3

      More details

  • Hokkaido University   Research Institute of Electronic Science   Assistant Professor

    2015.7 - 2020.3

      More details

  • University of Fribourg   Adolphe Merkle Institute ( Prof. C. Weder)   Postdoctoral Research Fellow (JSPS Postdoctoral Fellow for Research Abroad)

    2013.7 - 2015.6

      More details

  • the University of Tokyo   Graduate School of Pharmaceutical Sciences   project researcher

    2013.4 - 2013.5

      More details

  • the University of Tokyo   Graduate School of Pharmaceutical Sciences   Postdoctoral Research Fellow (JSPS Research Fellow)

    2010.4 - 2013.3

      More details

  • the University of Tokyo   Department of Chemistry and Biotechnology, School of Engineering   Postdoctoral Research Fellow (JSPS Research Fellow)(DC2→PD)

    2009.4 - 2010.3

      More details

▼display all

Professional Memberships

Committee Memberships

  •   高分子学会 行事委員会委員  

    2024.6   

      More details

Papers

  • Rotaxane‐Based Mechanochromic Mechanophore Enabled by Amide Bond Formation Invited Reviewed International journal

    Yuto Yoshida, Yoshimitsu Sagara

    Chemistry – An Asian Journal   20 ( 10 )   2025.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    Abstract

    Mechanochromic mechanophores are molecular structures that alter their absorption and fluorescence properties in response to applied mechanical force. Supramolecular mechanophores, which operate without requiring covalent bond cleavage, respond to smaller forces with instantaneous and reversible fluorescence changes. Rotaxane‐based supramolecular mechanophores offer exceptional design flexibility due to their molecular structures. However, previously reported rotaxane mechanophores have predominantly relied on azide‐alkyne Huisgen cycloaddition for the final rotaxane formation, which restricts the incorporation of azide or alkyne functional groups within the resulting rotaxane structure. This study presents a novel approach for synthesizing rotaxane mechanophores by constructing the axle molecule through amide bond formation between a succinimidyl ester and an amino group. Polyurethane elastomer films containing the rotaxane mechanophore exhibited a rapid and reversible on/off switch in green fluorescence from 9,10‐bis(phenylethynyl)anthracene upon cycle stretching. The new mechanophore demonstrated force‐responsive behavior comparable to previously reported rotaxane mechanophores. The amide bond formation strategy enables the incorporation of diverse functional groups into rotaxane‐based mechanophores, significantly broadening their potential applications.

    DOI: 10.1002/asia.202401826

    researchmap

  • Enhanced Photothermal Property of Dithienoindacenodithiophene Molecules by [2 + 2] Cycloaddition–Retroelectrocyclization Reaction for Efficient Solar Steam Generation Reviewed International coauthorship International journal

    Chia Yang Lin, Shohei Shimizu, Yoshimitsu Sagara, Hidetoshi Matsumoto, Tsuyoshi Michinobu

    Solar RRL   2025

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/solr.202400803

    Scopus

    researchmap

  • Quenching mechanism in rotaxane mechanophores: insights from acene-based luminophores

    Keigo Nonaka, Hayato Sakai, Ryusei Mori, Naoki Shimada, Shunsuke Hatatsu, Taku Hasobe, Yoshimitsu Sagara

    Chemical Science   16 ( 45 )   21534 - 21541   2025

     More details

    Publishing type:Research paper (scientific journal)   Publisher:Royal Society of Chemistry (RSC)  

    The quenching mechanism of the rotaxane mechanochromic mechanophore is investigated with a series of π-extended acene groups. Photoinduced electron transfer is found to be primarily responsible for the quenching.

    DOI: 10.1039/d5sc05343a

    researchmap

  • Complete suppression of fluorescence from a 9,10-bis(phenylethynyl)anthracene-based ring upon [2]catenane formation Reviewed International journal

    Fazil Salim Thuluvanchery, Nobuyuki Tamaoki, Yoshimitsu Sagara

    Bulletin of the Chemical Society of Japan   97 ( 12 )   2024.11

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Oxford University Press (OUP)  

    Abstract

    We report the synthesis and characterization of a [2]catenane consisting of one fluorescent ring incorporating a 9,10-bis(phenylethynyl)anthracene and the other ring containing 2 naphthalene diimides as quenchers. The catenane was constructed via a modified Huisgen 1,3-dipolar cycloaddition between terminal alkyne and azide groups, introduced into precursors of the quencher ring in the presence of the fluorescent ring. In chloroform, the absorption spectra of the catenane showed a broad band between 500 and 700 nm, attributed to charge-transfer interactions between the fluorophore and quenchers. Titration experiments using a quencher ring and linear model compounds of the fluorescent ring suggested that the fluorophore in [2]catenane is sandwiched between the 2 quenchers. This configuration led to substantial shifts in the ¹H NMR signals of the fluorophore, compared to the free 9,10-bis(phenylethynyl)anthracene of the ring before catenane formation. While the fluorescent ring exhibited a high fluorescence quantum yield (Φ = 0.91), this was completely quenched upon catenane formation (Φ < 0.01). This pronounced fluorescence quenching makes the system a promising candidate for the development of supramolecular mechanophores capable of on/off fluorescence switching in response to applied force.

    DOI: 10.1093/bulcsj/uoae135

    researchmap

  • Coordination of hydrogen-bonding and π–π stacking induced elasticity and efficient optical-waveguiding in 4,7-bis(phenyl ethynyl)benzo[c][1,2,5] thiadiazole-based crystals Reviewed International coauthorship International journal

    Geng Li, Yan Xia, Kunpeng Guo, Jie Li, Yongli Yan, Yoshimitsu Sagara, Yongzhen Yang

    Journal of Materials Chemistry C   12 ( 37 )   14997 - 15003   2024.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Royal Society of Chemistry (RSC)  

    DOI: 10.1039/d4tc02511c

    Scopus

    researchmap

  • Tetracene cyclophanes showing controlled intramolecular singlet fission by through-space orientations. Reviewed International journal

    Hayato Sakai, Keigo Nonaka, Ryo Hayasaka, Shakkeeb Thazhathethil, Yoshimitsu Sagara, Taku Hasobe

    Chemical communications (Cambridge, England)   60 ( 30 )   4084 - 4087   2024.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    Tetracene cyclophanes: a series of cyclic tetracene dimers bridged by two flexible ethylene glycol units demonstrated enhanced intramolecular singlet fission through through-space orientations by suppressing the H-type excited complex.

    DOI: 10.1039/d4cc00278d

    PubMed

    researchmap

  • Grinding‐Induced Water Solubility Exhibited by Mechanochromic Luminescent Supramolecular Fibers Reviewed International journal

    Qiming Liu, Tianyue Zhang, Yuka Ikemoto, Yudai Shinozaki, Go Watanabe, Yuta Hori, Yasuteru Shigeta, Takemi Midorikawa, Koji Harano, Yoshimitsu Sagara

    Small   2024.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Wiley  

    Abstract

    Most mechanochromic luminescent compounds are crystalline and highly hydrophobic; however, mechanochromic luminescent molecular assemblies comprising amphiphilic molecules have rarely been explored. This study investigated mechanochromic luminescent supramolecular fibers composed of dumbbell‐shaped 9,10‐bis(phenylethynyl)anthracene‐based amphiphiles without any tetraethylene glycol (TEG) substituents or with two TEG substituents. Both amphiphiles formed water‐insoluble supramolecular fibers via linear hydrogen bond formation. Both compounds acquired water solubility when solid samples composed of supramolecular fibers are ground. Grinding induces the conversion of 1D supramolecular fibers into micellar assemblies where fluorophores can form excimers, thereby resulting in a large redshift in the fluorescence spectra. Excimer emission from the ground amphiphile without TEG chains is retained after dissolution in water. The micelles are stable in water because hydrophilic dendrons surround the hydrophobic luminophores. By contrast, when water is added to a ground amphiphile having TEG substituents, fragmented supramolecular fibers with the same molecular arrangement as the initial supramolecular fibers are observed, because fragmented fibers are thermodynamically preferable to micelles as the hydrophobic arrays of fluorophores are covered with hydrophilic TEG chains. This leads to the recovery of the initial fluorescent properties for the latter amphiphile. These supramolecular fibers can be used as practical mechanosensors to detect forces at the mesoscale.

    DOI: 10.1002/smll.202400063

    researchmap

  • A rotaxane-based supramolecular mechanophore featuring a pyridine group in the luminophore

    Mori, R., Sagara, Y.

    Chemistry Letters   53 ( 1 )   2024.1

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1093/chemle/upae006

    Scopus

    researchmap

  • Enhanced Photothermal Property of NDI-Based Conjugated Polymers by Copolymerization with a Thiadiazolobenzotriazole Unit

    Wang, M., Lin, C.-Y., Sagara, Y., Michinobu, T.

    ACS Materials Au   4 ( 1 )   2024.1

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/acsmaterialsau.3c00077

    Scopus

    researchmap

  • Water-dispersible donor–acceptor–donor π-conjugated bolaamphiphiles enabling a humidity-responsive luminescence color change

    Tomoya Enjou, Shimpei Goto, Qiming Liu, Fumitaka Ishiwari, Akinori Saeki, Taro Uemtasu, Yuka Ikemoto, Sora Watanabe, Go Matsuba, Kouichiro Ishibashi, Go Watanabe, Satoshi Minakata, Yoshimitsu Sagara, Youhei Takeda

    Chemical Communications   2024

     More details

    Publishing type:Research paper (scientific journal)   Publisher:Royal Society of Chemistry (RSC)  

    Water-dispersible fluorescent bolaamphiphiles have been developed. Also, luminescence color change in response to humidity has been demonstrated with a composite material.

    DOI: 10.1039/d3cc05749f

    researchmap

  • Ring-size dependent ratiometric photoluminescence of cyclophane mechanophores Reviewed International coauthorship International journal

    Thazhathethil, S., Thuluvanchery, F.S., Shimizu, S., Scarlat, I., Clough, J.M., Weder, C., Sagara, Y.

    Journal of Materials Chemistry C   12 ( 17 )   2024

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/d4tc00244j

    Scopus

    researchmap

  • Novel Solid-State Fluorophores, a Series of Cyanostilbene-Based Amorphous Molecular Materials Reviewed International journal

    Fukushima, H., Miyagishi, K., Mori, K., Sagara, Y., Kokado, K., Tamaoki, N., Nakamura, T., Nakano, H.

    ChemPhotoChem   8 ( 11 )   2024

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/cptc.202400169

    Scopus

    researchmap

  • Mechanical (De)Activation of Rotaxane Mechanophores: Axle Length Matters

    Mori, R., Weder, C., Sagara, Y.

    Macromolecules   56 ( 22 )   2023.11

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/acs.macromol.3c01686

    Scopus

    researchmap

  • Force-Induced Shuttling of Rotaxanes Controls Fluorescence Resonance Energy Transfer in Polymer Hydrogels

    Muramatsu, T., Shimizu, S., Clough, J.M., Weder, C., Sagara, Y.

    ACS Applied Materials and Interfaces   15 ( 6 )   2023.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/acsami.2c20904

    Scopus

    researchmap

  • Tuning the mechanoresponsive luminescence of rotaxane mechanophores by varying the stopper size

    Keiko Hiratsuka, Tatsuya Muramatsu, Takuya Seki, Christoph Weder, Go Watanabe, Yoshimitsu Sagara

    Journal of Materials Chemistry C   11 ( 12 )   3949 - 3955   2023

     More details

    Publishing type:Research paper (scientific journal)   Publisher:Royal Society of Chemistry (RSC)  

    The efficiency of force-induced dethreading of rotaxane mechanophores is controlled by the stopper size.

    DOI: 10.1039/d3tc00330b

    researchmap

  • Microscopic strain mapping in polymers equipped with non-covalent mechanochromic motifs

    Traeger, H., Kiebala, D., Calvino, C., Sagara, Y., Schrettl, S., Weder, C., Clough, J.M.

    Materials Horizons   10 ( 9 )   2023

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/d3mh00650f

    Scopus

    researchmap

  • Mechanochromic luminescence of phase-separated hydrogels that contain cyclophane mechanophores

    Shimizu, S., Yoshida, H., Mayumi, K., Ajiro, H., Sagara, Y.

    Materials Chemistry Frontiers   7 ( 18 )   2023

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/d3qm00579h

    Scopus

    researchmap

  • Excited State Charge-Transfer Complexes Enable Fluorescence Color Changes in a Supramolecular Cyclophane Mechanophore

    Shakkeeb Thazhathethil, Tatsuya Muramatsu, Nobuyuki Tamaoki, Christoph Weder, Yoshimitsu Sagara

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   61 ( 42 )   2022.10

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/anie.202209225

    Web of Science

    researchmap

  • Supramolecular Rings as Building Blocks for Stimuli-Responsive Materials

    Traeger, H., Ghielmetti, A., Sagara, Y., Schrettl, S., Weder, C.

    Gels   8 ( 6 )   2022.6

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.3390/gels8060350

    Scopus

    researchmap

  • Strain-correlated mechanochromism in different polyurethanes featuring a supramolecular mechanophore

    Traeger, H., Sagara, Y., Berrocal, J.A., Schrettl, S., Weder, C.

    Polymer Chemistry   13 ( 19 )   2022

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/d2py00218c

    Web of Science

    Scopus

    researchmap

  • Crystal Structure of a 4,7-Bis(phenylethynyl)-2,1,3-benzothiadiazole-Based Cyclophane and the Mechanoresponsive Luminescence

    Hiratsuka, K., Salim, F.T., Takahashi, K., Nakamura, T., Sagara, Y.

    Bulletin of the Chemical Society of Japan   95 ( 10 )   2022

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1246/bcsj.20220216

    Web of Science

    Scopus

    researchmap

  • Crystal structure of a 1,6-bis(phenylethynyl)pyrene-based cyclophane that exhibits mechanochromic luminescence

    Shohei Shimizu, Shakkeeb Thazhathethil, Kiyonori Takahashi, Takayoshi Nakamura, Yoshimitsu Sagara

    MOLECULAR SYSTEMS DESIGN & ENGINEERING   6 ( 12 )   1039 - 1046   2021.11

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/d1me00131k

    Web of Science

    researchmap

  • Rotaxane-Based Dual Function Mechanophores Exhibiting Reversible and Irreversible Responses

    Tatsuya Muramatsu, Yuji Okado, Hanna Traeger, Stephen Schrettl, Nobuyuki Tamaoki, Christoph Weder, Yoshimitsu Sagara

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   143 ( 26 )   9884 - 9892   2021.7

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/jacs.1c03790

    Web of Science

    researchmap

  • Folded Perylene Diimide Loops as Mechanoresponsive Motifs

    Hanna Traeger, Yoshimitsu Sagara, Derek J. Kiebala, Stephen Schrettl, Christoph Weder

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   2021.6

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/anie.202105219

    Web of Science

    researchmap

  • Mechanically Responsive Luminescent Polymers Based on Supramolecular Cyclophane Mechanophores

    Yoshimitsu Sagara, Hanna Traeger, Jie Li, Yuji Okado, Stephen Schrettl, Nobuyuki Tamaoki, Christoph Weder

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   143 ( 14 )   5519 - 5525   2021.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/jacs.1c01328

    Web of Science

    researchmap

  • Two-step mechanoresponsive luminescence and mechanical stimuli-induced release of small molecules exhibited by a luminescent cyclophane

    Yoshimitsu Sagara, Kiyonori Takahashi, Atsushi Seki, Tatsuya Muramatsu, Takayoshi Nakamura, Nobuyuki Tamaoki

    JOURNAL OF MATERIALS CHEMISTRY C   9 ( 5 )   1671 - 1677   2021.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/d0tc04853d

    Web of Science

    researchmap

  • Mechanical and thermal stimuli-induced release of toluene included in luminescent crystals as one-dimensional solvent channels Reviewed

    Yoshimitsu Sagara, Kiyonori Takahashi, Takayoshi Nakamura, Nobuyuki Tamaoki

    JOURNAL OF MATERIALS CHEMISTRY C   8 ( 29 )   10039 - 10046   2020.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/d0tc02473b

    Web of Science

    researchmap

  • Mechanochromic Luminescence from Crystals Consisting of Intermolecular Hydrogen-Bonded Sheets Reviewed

    Yoshimitsu Sagara, Kiyonori Takahashi, Takayoshi Nakamura, Nobuyuki Tamaoki

    CHEMISTRY-AN ASIAN JOURNAL   15 ( 4 )   478 - 482   2020.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/asia.201901679

    Web of Science

    researchmap

  • Crystal structure and thermoresponsive luminescence of a 9,10-bis(phenylethynyl)anthracene-based cyclophane Reviewed

    Yoshimitsu Sagara, Kiyonori Takahashi, Takayoshi Nakamura, Nobuyuki Tamaoki

    MOLECULAR SYSTEMS DESIGN & ENGINEERING   5 ( 1 )   205 - 211   2020.1

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c9me00105k

    Web of Science

    researchmap

  • Mechanoresponsive Behavior of a Polymer-Embedded Red-Light Emitting Rotaxane Mechanophore Reviewed

    Muramatsu, T., Sagara, Y., Traeger, H., Tamaoki, N., Weder, C.

    ACS Applied Materials and Interfaces   11 ( 27 )   24571 - 24576   2019.7

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/acsami.9b06302

    Web of Science

    Scopus

    researchmap

  • Rotaxane-Based Mechanophores Enable Polymers with Mechanically Switchable White Photoluminescence Reviewed

    Yoshimitsu Sagara, Marc Karman, Atsushi Seki, Mehboobali Pannipara, Nobuyuki Tamaoki, Christoph Weder

    ACS Central Science   5 ( 5 )   874 - 881   2019.5

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/acscentsci.9b00173

    Web of Science

    Scopus

    researchmap

  • Mechano- and Photoresponsive Behavior of a Bis(cyanostyryl)benzene Fluorophore Reviewed

    Kaneko, R., Sagara, Y., Katao, S., Tamaoki, N., Weder, C., Nakano, H.

    Chemistry - A European Journal   25 ( 24 )   6162 - 6169   2019.4

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/chem.201900120

    Web of Science

    Scopus

    researchmap

  • Temperature-Controlled Locally Excited and Twisted Intramolecular Charge-Transfer State-Dependent Fluorescence Switching in Triphenylamine-Benzothiazole Derivatives Reviewed

    Kundu, A., Karthikeyan, S., Sagara, Y., Moon, D., Anthony, S.P.

    ACS Omega   4 ( 3 )   5147 - 5154   2019.3

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/acsomega.8b03099

    Web of Science

    Scopus

    researchmap

  • Functional polymers through mechanochemistry Reviewed

    Schrettl, S., Balkenende, D.W.R., Calvino, C., Karman, M., Lavrenova, A., Neumann, L.N., Sagara, Y., Verde-Sesto, E., Di Giannantonio, M., Simon, Y.C., Fromm, K.M., Lattuada, M., Weder, C.

    Chimia   73 ( 1-2 )   7 - 11   2019.2

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.2533/chimia.2019.7

    Web of Science

    Scopus

    researchmap

  • A 1,6-Diphenylpyrene-Based, Photoluminescent Cyclophane Showing a Nematic Liquid-Crystalline Phase at Room Temperature Reviewed

    Sagara Yoshimitsu, Muramatsu Tatsuya, Tamaoki Nobuyuki

    CRYSTALS   9 ( 2 )   2019.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.3390/cryst9020092

    Web of Science

    researchmap

  • Mechanoresponsive, Luminescent Polymer Blends Based on an Excimer-Forming Telechelic Macromolecule Reviewed

    Calvino, C., Sagara, Y., Buclin, V., Haehnel, A.P., del Prado, A., Aeby, C., Simon, Y.C., Schrettl, S., Weder, C.

    Macromolecular Rapid Communications   40 ( 1 )   2019.1

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/marc.201800705

    Web of Science

    Scopus

    researchmap

  • Unusual fluorescent photoswitching of imidazole derivatives: The role of molecular conformation and twist angle controlled organic solid state fluorescence Reviewed

    Kundu, A., Karthikeyan, S., Sagara, Y., Moon, D., Anthony, S.P.

    Physical Chemistry Chemical Physics   20 ( 43 )   27385 - 27393   2018.11

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c8cp05355c

    Web of Science

    Scopus

    researchmap

  • Cyclophane-Based Fluorescence Tuning Induced by Hydrostatic Pressure Changes Reviewed

    Sagara Yoshimitsu, Tamaoki Nobuyuki, Fukuhara Gaku

    CHEMPHOTOCHEM   2 ( 11 )   959 - 963   2018.11

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/cptc.201800163

    Web of Science

    researchmap

  • Linearly polarized photoluminescence from an asymmetric cyclophane showing thermo- and mechanoresponsive luminescence Reviewed

    Sagara Yoshimitsu, Seki Atsushi, Kim Yuna, Tamaoki Nobuyuki

    JOURNAL OF MATERIALS CHEMISTRY C   6 ( 31 )   8453 - 8459   2018.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c8tc02919a

    Web of Science

    researchmap

  • Drastic Modulation of Stimuli-Responsive Fluorescence by a Subtle Structural Change of Organic Fluorophore and Polymorphism Controlled Mechanofluorochromism Reviewed

    Hariharan, P.S., Parthasarathy, G., Kundu, A., Karthikeyan, S., Sagara, Y., Moon, D., Anthony, S.P.

    Crystal Growth and Design   18 ( 7 )   3971 - 3979   2018.7

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/acs.cgd.8b00310

    Web of Science

    Scopus

    researchmap

  • Stimuli-Responsive Dual-Color Photon Upconversion: A Singlet-to-Triplet Absorption Sensitizer in a Soft Luminescent Cyclophane Reviewed

    Kazuma Mase, Yoichi Sasaki, Yoshimitsu Sagara, Nobuyuki Tamaoki, Christoph Weder, Nobuhiro Yanai, Nobuo Kimizuka

    Angewandte Chemie - International Edition   57 ( 11 )   2806 - 2810   2018.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/anie.201712644

    Web of Science

    Scopus

    researchmap

  • Innentitelbild: Stimuli-Responsive Dual-Color Photon Upconversion: A Singlet-to-Triplet Absorption Sensitizer in a Soft Luminescent Cyclophane (Angew. Chem. 11/2018) Reviewed

    Kazuma Mase, Yoichi Sasaki, Yoshimitsu Sagara, Nobuyuki Tamaoki, Christoph Weder, Nobuhiro Yanai, Nobuo Kimizuka

    Angewandte Chemie   130 ( 11 )   2778   2018.3

     More details

    Publisher:Wiley-Blackwell  

    DOI: 10.1002/ange.201801896

    researchmap

  • Stimuli-Responsive Dual-Color Photon Upconversion: A Singlet-to-Triplet Absorption Sensitizer in a Soft Luminescent Cyclophane Reviewed

    Kazuma Mase, Yoichi Sasaki, Yoshimitsu Sagara, Nobuyuki Tamaoki, Christoph Weder, Nobuhiro Yanai, Nobuo Kimizuka

    Angewandte Chemie   130 ( 11 )   2856   2018.3

     More details

    Publisher:Wiley-Blackwell  

    DOI: 10.1002/ange.201712644

    researchmap

  • Inside Cover: Stimuli-Responsive Dual-Color Photon Upconversion: A Singlet-to-Triplet Absorption Sensitizer in a Soft Luminescent Cyclophane (Angew. Chem. Int. Ed. 11/2018) Reviewed

    Kazuma Mase, Yoichi Sasaki, Yoshimitsu Sagara, Nobuyuki Tamaoki, Christoph Weder, Nobuhiro Yanai, Nobuo Kimizuka

    Angewandte Chemie International Edition   57 ( 11 )   2730   2018.3

     More details

    Publisher:Wiley-Blackwell  

    DOI: 10.1002/anie.201801896

    researchmap

  • Rotaxanes as mechanochromic fluorescent force transducers in polymers Reviewed

    Yoshimitsu Sagara, Marc Karman, Ester Verde-Sesto, Kazuya Matsuo, Yuna Kim, Nobuyuki Tamaoki, Christoph Weder

    Journal of the American Chemical Society   140 ( 5 )   1584 - 1587   2018.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/jacs.7b12405

    Web of Science

    Scopus

    researchmap

  • Linearly polarized photoluminescence from an asymmetric cyclophane showing thermo- and mechanoresponsive luminescence Reviewed

    Yoshimitsu Sagara, Atsushi Seki, Yuna Kim, Nobuyuki Tamaoki

    Journal of Materials Chemistry C   6 ( 31 )   8453 - 8459   2018

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c8tc02919a

    Scopus

    researchmap

  • Asymmetric Cyclophanes Permit Access to Supercooled Nematic Liquid Crystals with Stimulus-Responsive Luminescence Reviewed

    Yoshimitsu Sagara, Christoph Weder, Nobuyuki Tamaoki

    CHEMISTRY OF MATERIALS   29 ( 14 )   6145 - 6152   2017.7

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/acs.chemmater.7b02220

    Web of Science

    researchmap

  • Mechano- and Thermoresponsive Photoluminescent Supramolecular Polymer Reviewed

    Anna Lavrenova, Diederik W. R. Balkenende, Yoshimitsu Sagara, Stephen Schrettl, Yoan C. Simon, Christoph Weder

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   139 ( 12 )   4302 - 4305   2017.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/jacs.7b00342

    Web of Science

    researchmap

  • Temperature-Dependent Mechanochromic Behavior of Mechanoresponsive Luminescent Compounds Reviewed

    Yoshimitsu Sagara, Kazuya Kubo, Takayoshi Nakamura, Nobuyuki Tamaoki, Christoph Weder

    CHEMISTRY OF MATERIALS   29 ( 3 )   1273 - 1278   2017.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/acs.chemmater.6b04720

    Web of Science

    researchmap

  • Unexpected Responses of Luminescent Molecular Materials Upon Simultaneous Exposure to Mechanical Force and Heat Reviewed

    Y. Sagara, K. Kubo, T. Nakamura, N. Tamaoki, C. Weder

    Chemistry of Materials   29   1273 - 1278   2017.1

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/acs.chemmater.6b04720

    researchmap

  • Mechanoresponsive luminescence and liquid-crystalline behaviour of a cyclophane featuring two 1,6-bis(phenylethynyl)pyrene groups Reviewed

    Yoshimitsu Sagara, Nobuyuki Tamaoki

    RSC ADVANCES   7 ( 74 )   47056 - 47062   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c7ra10776e

    Web of Science

    researchmap

  • A Thermo- and Mechanoresponsive Cyano-Substituted Oligo(p-phenylene vinylene) Derivative with Five Emissive States Reviewed

    Yoshimitsu Sagara, Anna Lavrenova, Aurelien Crochet, Yoan C. Simon, Katharina M. Fromm, Christoph Weder

    CHEMISTRY-A EUROPEAN JOURNAL   22 ( 13 )   4374 - 4378   2016.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/chem.201600272

    Web of Science

    researchmap

  • Mechanoresponsive Luminescent Molecular Assemblies: An Emerging Class of Materials Reviewed

    Yoshimitsu Sagara, Shogo Yamane, Masato Mitani, Christoph Weder, Takashi Kato

    ADVANCED MATERIALS   28 ( 6 )   1073 - 1095   2016.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/adma.201502589

    Web of Science

    PubMed

    researchmap

  • A mechano- and thermoresponsive luminescent cyclophane Reviewed

    Yoshimitsu Sagara, Yoan C. Simon, Nobuyuki Tamaoki, Christoph Weder

    CHEMICAL COMMUNICATIONS   52 ( 33 )   5694 - 5697   2016

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c6cc01614f

    Web of Science

    researchmap

  • Tuning the thermo- and mechanoresponsive behavior of luminescent cyclophanes Reviewed

    Yoshimitsu Sagara, Christoph Weder, Nobuyuki Tamaoki

    RSC ADVANCES   6 ( 84 )   80408 - 80414   2016

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c6ra18348d

    Web of Science

    researchmap

  • Mechanochemistry in Polymers with Supramolecular Mechanophores Reviewed

    Alexander P. Haehnel, Yoshimitsu Sagara, Yoan C. Simon, Christoph Weder

    POLYMER MECHANOCHEMISTRY   369   345 - 375   2015

     More details

    Language:English   Publishing type:Part of collection (book)  

    DOI: 10.1007/128_2015_640

    Web of Science

    PubMed

    researchmap

  • Thermal or mechanical stimuli-induced photoluminescence color change of a molecular assembly composed of an amphiphilic anthracene derivative in water Reviewed

    Yoshimitsu Sagara, Toru Komatsu, Takuya Terai, Tasuku Ueno, Kenjiro Hanaoka, Takashi Kato, Tetsuo Nagano

    Chemistry - A European Journal   20 ( 33 )   10397 - 10403   2014.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Wiley-VCH Verlag  

    DOI: 10.1002/chem.201403025

    Scopus

    PubMed

    researchmap

  • Thermal or Mechanical Stimuli-Induced Photoluminescence Color Change of a Molecular Assembly Composed of an Amphiphilic Anthracene Derivative in Water Reviewed

    Yoshimitsu Sagara, Toru Komatsu, Takuya Terai, Tasuku Ueno, Kenjiro Hanaoka, Takashi Kato, Tetsuo Nagano

    CHEMISTRY-A EUROPEAN JOURNAL   20 ( 33 )   10397 - 10403   2014.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/chem.201403025

    Web of Science

    PubMed

    researchmap

  • Covalent Attachment of Mechanoresponsive Luminescent Micelles to Glasses and Polymers in Aqueous Conditions Reviewed

    Yoshimitsu Sagara, Toru Komatsu, Tasuku Ueno, Kenjiro Hanaoka, Takashi Kato, Tetsuo Nagano

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   136 ( 11 )   4273 - 4280   2014.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/ja412670g

    Web of Science

    PubMed

    researchmap

  • A water-soluble mechanochromic luminescent pyrene derivative exhibiting recovery of the initial photoluminescence color in a high-humidity environment Reviewed

    Yoshimitsu Sagara, Toru Komatsu, Tasuku Ueno, Kenjiro Hanaoka, Takashi Kato, Tetsuo Nagano

    Advanced Functional Materials   23 ( 42 )   5277 - 5284   2013.11

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/adfm.201300180

    Scopus

    researchmap

  • Steric effects on excimer formation for photoluminescent smectic liquid-crystalline materials Reviewed

    Shogo Yamane, Yoshimitsu Sagara, Takashi Kato

    CHEMICAL COMMUNICATIONS   49 ( 37 )   3839 - 3841   2013

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c3cc00072a

    Web of Science

    PubMed

    researchmap

  • Mechanochromic luminescent liquid crystals based on a bianthryl moiety Reviewed

    Shogo Yamane, Yoshimitsu Sagara, Toshiki Mutai, Koji Araki, Takashi Kato

    JOURNAL OF MATERIALS CHEMISTRY C   1 ( 15 )   2648 - 2656   2013

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c3tc00861d

    Web of Science

    researchmap

  • Stimuli-Responsive Photoluminescent Liquid Crystals Reviewed

    Shogo Yamane, Kana Tanabe, Yoshimitsu Sagara, Takashi Kato

    LIQUID CRYSTALS: MATERIALS DESIGN AND SELF-ASSEMBLY   318   395 - 405   2012

     More details

    Language:English   Publishing type:Part of collection (book)  

    DOI: 10.1007/128_2011_275

    Web of Science

    PubMed

    researchmap

  • Brightly Tricolored Mechanochromic Luminescence from a Single-Luminophore Liquid Crystal: Reversible Writing and Erasing of Images Reviewed

    Yoshimitsu Sagara, Takashi Kato

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   50 ( 39 )   9128 - 9132   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/anie.201100914

    Web of Science

    PubMed

    researchmap

  • A mechanical and thermal responsive luminescent liquid crystal forming a colourless film under room light Reviewed

    Yoshimitsu Sagara, Takashi Kato

    SUPRAMOLECULAR CHEMISTRY   23 ( 3-4 )   310 - 314   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1080/10610278.2010.527980

    Web of Science

    researchmap

  • Piezochromic luminescence of amide and ester derivatives of tetraphenylpyrene-role of amide hydrogen bonds in sensitive piezochromic response Reviewed

    Mitsutaka Sase, Shingo Yamaguchi, Yoshimitsu Sagara, Isao Yoshikawa, Toshiki Mutai, Koji Araki

    JOURNAL OF MATERIALS CHEMISTRY   21 ( 23 )   8347 - 8354   2011

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/c0jm03950k

    Web of Science

    researchmap

  • Mechanically induced luminescence changes in molecular assemblies Reviewed

    Yoshimitsu Sagara, Takashi Kato

    NATURE CHEMISTRY   1 ( 8 )   605 - 610   2009.11

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1038/NCHEM.411

    Web of Science

    PubMed

    researchmap

  • A Stimuli-Responsive, Photoluminescent, Anthracene-Based Liquid Crystal: Emission Color Determined by Thermal and Mechanical Processes Reviewed

    Yoshimitsu Sagara, Shogo Yamane, Toshiki Mutai, Koji Araki, Takashi Kato

    ADVANCED FUNCTIONAL MATERIALS   19 ( 12 )   1869 - 1875   2009.6

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/adfm.200801726

    Web of Science

    researchmap

  • A thermoresponsive photoluminescent smectic liquid crystal: change of photoluminescent color on the smectic-smectic phase transition Reviewed

    Shogo Yamane, Yoshimitsu Sagara, Takashi Kato

    CHEMICAL COMMUNICATIONS   ( 24 )   3597 - 3599   2009

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/b902848j

    Web of Science

    PubMed

    researchmap

  • Stimuli-responsive luminescent liquid crystals: Change of photoluminescent colors triggered by a shear-induced phase transition Reviewed

    Yoshimitsu Sagara, Takashi Kato

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   47 ( 28 )   5175 - 5178   2008

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1002/anie.200800164

    Web of Science

    PubMed

    researchmap

  • Uniaxially parallel alignment of a smectic a liquid-crystalline rod-coil molecule and its lithium salt complexes using rubbed polyimides Reviewed

    Yosuke Iinuma, Kenji Kishimoto, Yoshimitsu Sagara, Masafumi Yoshio, Tomohiro Mukai, Ichiro Kobayashi, Hiroyuki Ohno, Takashi Kato

    MACROMOLECULES   40 ( 14 )   4874 - 4878   2007.7

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/ma070160w

    Web of Science

    researchmap

  • Material design for piezochromic luminescence: Hydrogen-bond-directed assemblies of a pyrene derivative Reviewed

    Yoshimitsu Sagara, Toshiki Mutai, Isao Yoshikawa, Koji Araki

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   129 ( 6 )   1520 - +   2007.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1021/ja0677362

    Web of Science

    PubMed

    researchmap

  • Two dimensionally ion-conductive liquid crystals of cholesterol/tetra(ethylene oxide) block molecules Reviewed

    K Kishimoto, Y Sagara, T Kato, T Mukai, H Ohno, N Tamaoki

    MOLECULAR CRYSTALS AND LIQUID CRYSTALS   435   777 - 785   2005

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1080/15421400590954623

    Web of Science

    researchmap

  • Ion-Conductive Liquid Crystalline Chemical Gels: Formation of Hierarchical Phase-Segregated Structures and Functionalization

    KISHIMOTO Kenji, SAGARA Yoshimitsu, MUKAI Tomohiro, OHNO Hiroyuki, KATO Takashi

    Proceedings of Japanese Liquid Crystal Society Annual meeting   2004   81 - 81   2004

     More details

    Publisher:Japanese Liquid Crystal Society  

    Anisotropically ion-conductive liquid crystalline (LC) chemical gels have been prepared by photopolymerization for the complexes of ion-conductive liquid crystals, lithium salts and polymerizable compounds. The X-ray diffraction measurements and the field-emission scanning electron micrographs revealed that the LC gels have highly oriented hierarchical phase-segregated structures in nano- and micrometer levels. These organized LC gels have potentials for the application as a new type of ion-active materials. The structural analysis and anisotropic ionic conductivities are discussed.

    DOI: 10.11538/ekitou.2004.0.81.0

    CiNii Books

    researchmap

▼display all

MISC

▼display all

Awards

  • 島津奨励賞

    2023.2   公益財団法人 島津科学技術振興財団  

    相良剛光

     More details

  • ATI奨励賞

    2021.5   公益財団法人新世代研究所  

    相良剛光

     More details

  • The Suematsu Challenging Research Award

    2020.7   Tokyo Institute of Technology  

     More details

  • 広報委員会パブリシティ賞

    2019.11   高分子学会  

     More details

  • 平成 31 年度 文部科学大臣表彰 若手科学者賞

    2019.4   文部科学省  

    相良剛光

     More details

  • 田中ゴム科学技術賞

    2018.2   公益財団法人江野科学振興財団  

    相良剛光

     More details

  • 日本液晶学会論文賞A

    2012.9   日本液晶学会  

    相良剛光

     More details

  • 奨励賞

    2012.1   日本MRS  

    相良剛光

     More details

  • 第18回ポリマー材料フォーラム優秀発表賞

    2009.11   高分子学会  

    相良剛光

     More details

  • 工学系研究科長賞

    2009.3   東京大学 工学系研究科  

    相良剛光

     More details

  • 虹彩賞

    2008.9   日本液晶学会  

    相良剛光

     More details

▼display all

Research Projects

  • Science of Meso-Hierarchy

    Grant number:23H04872  2023.4 - 2028.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Transformative Research Areas (A)

      More details

    Grant amount:\140660000 ( Direct Cost: \108200000 、 Indirect Cost:\32460000 )

    researchmap

  • メゾメカノ機能材料

    Grant number:23H04878  2023.4 - 2028.3

    日本学術振興会  科学研究費助成事業  学術変革領域研究(A)

    相良 剛光, 河野 正規, 阿部 二朗

      More details

    Grant amount:\138840000 ( Direct Cost: \106800000 、 Indirect Cost:\32040000 )

    本学術変革領域では、分子がメゾスコピック領域で階層的に集合したメゾヒエラルキー材料を開発することが一つの主眼となっている。本A03-2班は、メゾヒエラルキー構造の特異な階層性を利用したメカノ機能性材料を開拓することを目指している。1分子の幅しか持たないメカノクロミック蛍光ファイバーに、メゾヒエラルキーの概念を導入し、力に応答して蛍光特性の可逆線形変化、蛍光特性の多段階変化、光応答性等を示すメゾメカノ機能材料を創製する。また、空孔錯体を用いた構造解析法により、分子集合構造変化と蛍光特性変化との相関関係を解明する。さらに新規フォトクロミック化合物を導入することにより機能性を拡張することを最終目標としている。その一方で、領域内で開発されるメゾヒエラルキー物質が生み出す力を可視化するための超分子メカノフォアを領域内に幅広く提供することも併せて目指す。
    初年度では、領域内共同研究により、ダンベル状の両親媒性分子が形成する1次元状の超分子ファイバーが示すメカノクロミック蛍光特性を解明した。両親媒性分子の疎水性蛍光団に導入したテトラエチレングリコール鎖の有無で、外部刺激に対する応答性が劇的に変化することが明らかとなり、その原因も明らかにすることができた。一方で、空孔錯体を用いた構造解析法を用いて、A01班で開発されたバルビツール酸誘導体が形成する分子集合構造の解明にも成功した。さらに、新規フォトクロミック機能に関しては、液晶散逸構造の研究基盤となる高速逆フォトクロミック分子の開発を推し進めた。これまでの逆フォトクロミック分子では数分程度要していた熱戻り反応を数秒まで高速化した新規キラル逆フォトクロミック分子の開発に成功した。

    researchmap

  • 新規動作機構を導入したロタキサン型超分子メカノフォアの機能開拓

    Grant number:23K26728  2023.4 - 2026.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    相良 剛光

      More details

    Grant amount:\18850000 ( Direct Cost: \14500000 、 Indirect Cost:\4350000 )

    近年、機械的刺激を受けて、色の変化、小分子の放出、触媒作用の誘起などの多様なアウトプットを示す「メカノフォア」と呼ばれる分子骨格が盛んに研究されている。我々は共有結合を切断する必要がないロタキサン型超分子メカノフォアを開発し、これらのメカノフォアを導入したポリマーフィルムが伸縮に応じて蛍光をOn/Offスイッチすることを明らかとしてきた。しかし現状、力の印加履歴記録に適したロタキサン型超分子メカノフォアは未開拓であり、導入する蛍光団の選択肢の幅が狭いなどの課題に直面している。そこで本研究では、ロタキサン型超分子メカノフォアに新しい動作機構を導入することでこれらの課題を克服し、当該メカノフォアが高い汎用性・実用性を兼ね備えたメカノフォアであることを実証する。具体的には、①蛍光強度の不可逆変化のみを示すメカノフォア、及び、②回転抑制発光機構を組み込んだメカノフォアの二種類を開発し、機能設計自由度を格段に拡張することを目指している。
    研究初年度の本年は、研究項目①に関して、軸分子の長さを短くしたロタキサンの合成を行った。このロタキサンには先行研究で力で環状構造がすり抜けることが分かっているストッパー構造を導入した。得られたロタキサンを従来と同じ重付加反応を用いてポリウレタンエラストマーに導入したところ、伸縮による蛍光強度の大きな変化はほぼ観察されず、伸縮を繰り返すと除荷時の蛍光強度が徐々に上昇することが分かった。これは目的の機能が達成できている結果となったが、今後、従来の共有結合切断型のメカノフォアとのactivation挙動の比較が必要である。研究項目②に関しても合成スキームの確立ができ、ロタキサンの合成に成功した。評価方法を次年度より模索する予定である。

    researchmap

  • 水圏機能材料の内部で発生する力を可視化する超分子メカノフォアの開発

    Grant number:22H04531  2022.4 - 2024.3

    日本学術振興会  科学研究費助成事業  新学術領域研究(研究領域提案型)

    相良 剛光

      More details

    Grant amount:\4680000 ( Direct Cost: \3600000 、 Indirect Cost:\1080000 )

    近年、機械的刺激を受けて様々なアウトプットを示す「メカノフォア」と呼ばれる分子骨格が盛んに研究されている。しかし従来のメカノフォアは吸収・蛍光特性の変化を誘起するために共有結合の切断が必要となり、弱い分子間相互作用が重要な役割を果たす水圏機能材料に印加されるor生み出す力を評価するには不向きである。そこで本研究では、シクロファンの環状構造を積極活用した「蛍光のOn/Offスイッチを示す親水性のシクロファン型超分子メカノフォア」を創製することを目指した。このメカノフォアをNCゲルなどのヒドロゲルに導入することにより、機械的刺激によって蛍光がOn/Offスイッチする水圏機能材料を創製することを最終目標とした。
    初年度では、まず水溶性を担保するために蛍光団にピリジニウム塩を導入し、その蛍光性がどのように変化するか、また、他のπ共役部位を持つ分子と水中で混合することで効率的に蛍光が消光されるかを精査した。ピリジニウム塩を持つ蛍光団の合成は合成することができたが、その蛍光特性は元々の蛍光性分子と大きく異なることが分かった。量子化学計算を行ったところ、予想されていたことではあるが、HOMO-LUMOレベルも大きく変化していることが明らかとなった。目的のメカノフォアを得るためにはさらなる分子構造探索が必須となることが分かり、水溶性の超分子メカノフォア開発に関する多くの知見を得ることができた。その一方で、第一期の公募研究の研究課題を継続して推進した結果、脂溶性の超分子メカノフォアではあるものの、ヒドロゲルへの導入に成功し、論文として纏めることができた。
    残念ながら次年度は交付申請を辞退することとなってしまったが、本研究は引き続き継続する予定である。

    researchmap

  • 超分子メカノフォアライブラリーの構築と新分野創発

    2021 - 2027

    科学技術振興機構  戦略的な研究開発の推進 創発的研究支援事業 

    相良 剛光

      More details

    Authorship:Principal investigator 

    ロタキサンなどの特殊な超分子構造を積極活用した超分子メカノフォアを多数作製し、超分子メカノフォアライブラリーを構築します。これらの超分子メカノフォアは、pNオーダーの力を可視化・評価することができ、他分野での微細な力を観察したいというニーズにオンデマンドで応えることができます。最終的には我々の体を構成する細胞などの生体組織が1分子レベルで生み出す力の高精度解析を目指します。

    researchmap

    J-GLOBAL

  • Development of rotaxane-based supramolecular mechanophores utilizing FRET

    Grant number:20K21215  2020.7 - 2022.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Research (Exploratory)

    Sagara Yoshimitsu

      More details

    Grant amount:\6500000 ( Direct Cost: \5000000 、 Indirect Cost:\1500000 )

    Recently, molecular structures called "mechanophores," which show various outputs at the single molecule level in response to mechanical stimuli, have been studied. While most mechanophores reported so far require covalent bond cleavage, we are developing "supramolecular mechanophores" that change their fluorescent properties without covalent bond cleavage. In mechanophores based on the motif of rotaxane, high planarity has been required for the fluorophore. In this study, to overcome this problem, we have shown that an energy transfer mechanism can be introduced into rotaxane-based supramolecular mechanophores.

    researchmap

  • レシオ型の蛍光変化を示す超分子メカノフォアの創製と水圏機能材料への応用

    Grant number:20H05198  2020.4 - 2022.3

    日本学術振興会  科学研究費助成事業 新学術領域研究(研究領域提案型)  新学術領域研究(研究領域提案型)

    相良 剛光

      More details

    Grant amount:\4940000 ( Direct Cost: \3800000 、 Indirect Cost:\1140000 )

    本研究では、共有結合を切断することなくレシオメトリックな蛍光色変化を示す「シクロファン型超分子メカノフォア」を創製し、機械的刺激によって蛍光特性が変化する水圏機能材料を創製することを目指した。
    前年度の研究において、我々は、エキシマ-蛍光を示す蛍光団を二つ環状構造に導入したシクロファン型超分子メカノフォアの概念実証を、ポリウレタンをホストポリマーとして用いて行った。この成果を踏まえて今年度は、機械的刺激による蛍光特性変化をより大きくするために、開発した超分子メカノフォアをヒドロゲルに導入することを目指した。様々なヒドロゲル作製法を試み、最終的に、ポリウレタンウレアに導入することができた。このポリウレタンウレアは主鎖にカルボン酸を持ち、含水することでヒドロゲルにすることができ、さらに、数百%まで延伸できた。メカノフォアを導入したポリウレタンウレアを含水して得られたヒドロゲルは、前年度得られたポリウレタンと比較してエキシマ-蛍光の寄与が大きくなっており、さらに、延伸によって、モノマー蛍光に対するエキシマ-蛍光の比率が低下することが分かった。さらに力を除くと元の蛍光特性が回復し、ポリウレタンで行った時と同様に、良好な可逆性があることが明らかとなった。当初の期待に反して、ヒドロゲル中でエキシマ-支配的な蛍光特性とはならなかったものの、ヒドロゲルのような水圏機能材料に超分子メカノフォアを導入し、機械的刺激によって蛍光特性変化を確認できたのは大きな進展であると考えている。今後はより親水性の分子構造を持つ超分子メカノフォアを開発し、水圏機能材料に導入し、メカノ機能を発現させる予定である。

    researchmap

  • Development of Cyclophane-based Supramolecular Mechanophores and the Applications for Polymeric Materials

    Grant number:18H02024  2018.4 - 2022.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

    Sagara Yoshimitsu

      More details

    Grant amount:\17810000 ( Direct Cost: \13700000 、 Indirect Cost:\4110000 )

    Recently, mechanophores that change absorption and fluorescence properties responding to mechanical stimuli have been extensively studied. In this study, we developed a supramolecular mechanophore based on cyclophane. When cyclophane-based supramolecular mechanophores with one fluorophore and one quencher are introduced into polyurethane, the film obtained through solvent casting shows an orange fluorescence color derived from the charge-transfer complex between the fluorophore and quencher. When the film is stretched, the fluorophore and quencher are spatially separated and blue fluorescence from the fluorophore is observed. This ratiometric fluorescence color change is instantly reversible.

    researchmap

  • シクロファン型超分子メカノフォアの開拓と高分子材料への応用展開

    2018.4 - 2022.3

    日本学術振興会 科研費補助金  基盤研究B 

    相良剛光

      More details

    Authorship:Principal investigator  Grant type:Competitive

    researchmap

  • ロタキサン型メカノプローブの創製とメカノバイオロジーへの応用

    2017.10 - 2020

    科学技術振興機構  戦略的な研究開発の推進 戦略的創造研究推進事業 さきがけ 

    相良 剛光

      More details

    Authorship:Principal investigator  Grant type:Competitive

    超分子化学の分野で長年研究されてきたロタキサン構造を用いて、機械的刺激に応答して発光特性が変化する材料を開発します。開発される、いわゆる超分子メカノルミノファーを用いることで、細胞が生み出す微細な力を極限の感度で定量的に評価できる普遍的な新手法の開発に取り組みます。

    researchmap

    J-GLOBAL

  • 柔らかなシクロファンを用いた機械的刺激応答性発光材料の開発

    Grant number:16H00818  2016.4 - 2018.3

    日本学術振興会  科学研究費助成事業 新学術領域研究(研究領域提案型)  新学術領域研究(研究領域提案型)

    相良 剛光

      More details

    Grant amount:\6630000 ( Direct Cost: \5100000 、 Indirect Cost:\1530000 )

    近年、機械的刺激に応答して発光色が変化する材料が世界中で報告されている。本研究では、魅力的な三次元構造とホスト化合物としての有用性から、有機合成化学、超分子化学の分野で研究されてきたシクロファンに着目し、適切な分子骨格修飾を施す(柔らかさを導入する)ことにより、多様な機械的刺激応答性発光材料を開発することを目指している。本年度は前年度に得られた知見を基にいくつかのシクロファンを設計・合成し、その機能評価を行った。以下に主な研究成果を3つ列挙する。
    1. 発光部位として1,6-bis(phenylethynyl)pyrene部位を二つ持ち、それらの発光団をヘキサエチレングリコール鎖を介して連結したシクロファンの液晶性、及び外部刺激応答発光特性を精査した。
    2. 発光部位として9,10-bis(phenylethynyl)anthracene骨格を持つヘテロ型シクロファンを合成し、この化合物が過冷却ネマチック相を発現することを見出した。この過冷却ネマチック相は加熱操作により結晶相に相転移し、発光色が黄色から緑色に変化することがわかった。さらに、この化合物を三重項-三重項消滅に基づくフォトン・アップコンバージョンシステムのエネルギーアクセプターとして用いることでアップコンバージョン発光色の可逆制御にも成功した。
    3. シクロファンの内部空間を用いることでロタキサンを作製した。このロタキサンにポリウレタン鎖を導入することで伸縮により可逆的に発光特性が変化するエラストマーを開発することに成功した。

    researchmap

  • Development of water soluble mechanoresponsive luminescent materials with extended photofunction and the application to living tissues

    Grant number:16K17885  2016.4 - 2018.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)  Grant-in-Aid for Young Scientists (B)

    Sagara Yoshimitsu

      More details

    Grant amount:\4290000 ( Direct Cost: \3300000 、 Indirect Cost:\990000 )

    Molecular assembled materials that show mechanoresponsive luminescence were developed using amphiphilic copounds with hydrophilic dendritic groups. We discovered that the amphiphiles form one-dimensional supramolecular fibers and change the photoluminescence color in response to mechanical stimuli. It was also found that the emission band obtained through mechanical treatment shows blue- or red shift after exposure to methanol or water vapor. We examined the curious external stimuli-responsive luminescent behavior.

    researchmap

  • 準安定な分子集合体を利用した蛍光プローブの開発

    Grant number:10J07267  2010 - 2012

    日本学術振興会  科学研究費助成事業 特別研究員奨励費  特別研究員奨励費

    相良 剛光

      More details

    Grant amount:\2800000 ( Direct Cost: \2800000 )

    前年度までの本申請研究において、申請者は、機械的刺激と高湿度環境への暴露によって可逆的に発光色変化を示す水溶性ピレン誘導体や、水中で熱刺激・機械的刺激を受けて発光色が変化するミセルを開発してきた。このようなミセルは本申請研究の目的とする「生細胞にかかる機械的刺激を検知する蛍光プローブ」のプロトタイプとなり得た。
    そこで本年度は、実際に生細胞への応用を目指し、様々な検討を行った。具体的には、ミセルを構成する分子に多数導入された水酸基の一部をアミノ基に変換した化合物を設計・合成し、水中で機械的刺激を受けて発光色が変化することを確認した。その後、スルホスクシンイミジルエステルを両末端に持つ水溶性リンカーを用い、Hela細胞やHL60細胞の細胞膜上のタンパク質などに存在するアミノ基に導入し、生細胞イメージングを試みた。レーザー共焦点顕微鏡観察を行ったところ、細胞膜が綺麗に染まっていることが確認でき、ミセルが細胞膜上に導入されていることが分かった。機械的刺激を印加するために、ガラスビーズやポリマービーズを加えて振とうしてみたが、力が強すぎたために細胞自体が破壊されてしまった。
    そこで、細胞シート状にしたMDCK細胞を用いて、ミセルを導入したのちに細胞シート同士をこすり合わせる実験を行った。こすり合わせた細胞シートに対し、レーザー共焦点顕微鏡上で発光スペクトル測定を行ったが、こすり合わせる前後で有意な差は観察できなかった。その他、様々な方法を用いて、細胞膜上で機械的な刺激を受けたミセルの発光色変化を詳細に調べたが、有益な情報は得られなかった。今後は、より機械的刺激に対する感度を上げる分子設計を行う必要があると考えられる。

    researchmap

  • 準安定相を発現する液晶を利用した機能性材料の開発

    Grant number:08J07743  2008 - 2009

    日本学術振興会  科学研究費助成事業 特別研究員奨励費  特別研究員奨励費

    相良 剛光

      More details

    Grant amount:\1200000 ( Direct Cost: \1200000 )

    申請者は分子間相互作用を利用して発光部位を精密に配置し、その集積構造を変化させることで、バルク材料全体での発光特性の変化をねらった研究を行ってきた。二種類以上の発光部位の集積構造を作り出すため、分子間相互作用を競合させ、準安定相を誘起するという概念を導入している。本申請研究では秩序性と動的特性をあわせ持つソフトマテリアルである液晶に着目し、刺激に応答して発光色が変化する液晶材料の開発を行っている。前年度までに申請者はせん断という機械的刺激や熱刺激に応答して発光色が変化するピレン誘導体、アントラセン誘導体を開発した。本年度は、セキュリティ材料への応用を狙い、発光部位にナフタレンを導入した化合物を設計・合成した。このナフタレン誘導体は、等方相から急冷すると、準安定なミセルキュービック相を発現するが、徐冷すると安定なカラムナー相を発現する。キュービック相中ではナフタレン部位がエキシマー形成できる相関配置となり、水色の発光を示すが、カラムナー相中ではエキシマーは形成されず、青色の発光を示す。キュービック相を加熱すると128℃でカラムナー相に相転移する。また、128℃以下の温度でせん断を印加してもカラムナー相に相転移する。このナフタレン誘導体は液晶状態で可視領域にほとんど吸収を持たず、ガラス基板等に塗布しても、見た目には塗布してあることがわからない。そのため、セキュリティ材料などへの応用が期待できる。

    researchmap

▼display all

Social Activities

  • 力で光る色が変わる有機材料のメカニズム

    Role(s): Lecturer

    東京科学大学  2025年度 オープンキャンパス  2025.8

     More details

    Type:University open house

    researchmap

  • 伸ばすと光り方が変わるゴム材料 を体験しよう!

    Role(s): Planner

    東京科学大学  2025年度 オープンキャンパス  2025.8

     More details

    Type:University open house

    researchmap

  • 力で色の変わる有機材料のカラクリ

    Role(s): Lecturer

    東京工業大学  2024年度 オープンキャンパス  2024.8

     More details

    Type:University open house

    researchmap

  • 伸ばすと光るゴム材料を体験しよう!

    Role(s): Planner

    東京工業大学  2024年度 オープンキャンパス  2024.8

     More details

    Type:University open house

    researchmap

  • 伸ばすと光るゴム材料を体験しよう!

    Role(s): Planner

    東京工業大学  2023年度 オープンキャンパス  2023.8

     More details

    Type:University open house

    researchmap