1
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Wang ZJ, Wang S, Jiang J, Hu Y, Nakajima T, Maeda S, Craig SL, Gong JP. Effect of the Activation Force of Mechanophore on Its Activation Selectivity and Efficiency in Polymer Networks. J Am Chem Soc 2024; 146:13336-13346. [PMID: 38697646 DOI: 10.1021/jacs.4c01879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
In recent decades, more than 100 different mechanophores with a broad range of activation forces have been developed. For various applications of mechanophores in polymer materials, it is crucial to selectively activate the mechanophores with high efficiency, avoiding nonspecific bond scission of the material. In this study, we embedded cyclobutane-based mechanophore cross-linkers (I and II) with varied activation forces (fa) in the first network of the double network hydrogels and quantitively investigated the activation selectivity and efficiency of these mechanophores. Our findings revealed that cross-linker I, with a lower activation force relative to the bonds in the polymer main chain (fa-I/fa-chain = 0.8 nN/3.4 nN), achieved efficient activation with 100% selectivity. Conversely, an increase of the activation force of mechanophore II (fa-II/fa-chain = 2.5 nN/3.4 nN) led to a significant decrease of its activation efficiency, accompanied by a substantial number of nonspecific bond scission events. Furthermore, with the coexistence of two cross-linkers, significantly different activation forces resulted in the almost complete suppression of the higher-force one (i.e., I and III, fa-I/fa-III = 0.8 nN/3.4 nN), while similar activation forces led to simultaneous activations with moderate efficiencies (i.e., I and IV, fa-I/fa-IV = 0.8 nN/1.6 nN). These findings provide insights into the prevention of nonspecific bond rupture during mechanophore activation and enhance our understanding of the damage mechanism within polymer networks when using mechanophores as detectors. Besides, it establishes a principle for combining different mechanophores to design multiple mechanoresponsive functional materials.
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Affiliation(s)
- Zhi Jian Wang
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan
| | - Shu Wang
- Department of Chemistry, Duke University, Durham, North Carolina 27708-0346, United States
| | - Julong Jiang
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-8628, Japan
| | - Yixin Hu
- Department of Chemistry, Duke University, Durham, North Carolina 27708-0346, United States
| | - Tasuku Nakajima
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan
- Faculty of Advanced Life Science, Hokkaido University, Sapporo 001-0021, Japan
| | - Satoshi Maeda
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-8628, Japan
| | - Stephen L Craig
- Department of Chemistry, Duke University, Durham, North Carolina 27708-0346, United States
| | - Jian Ping Gong
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan
- Faculty of Advanced Life Science, Hokkaido University, Sapporo 001-0021, Japan
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2
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Fu X, Hu X. Ultrasound-Controlled Prodrug Activation: Emerging Strategies in Polymer Mechanochemistry and Sonodynamic Therapy. ACS Appl Bio Mater 2024. [PMID: 38698527 DOI: 10.1021/acsabm.4c00150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
Ultrasound has gained prominence in biomedical applications due to its noninvasive nature and ability to penetrate deep tissue with spatial and temporal resolution. The burgeoning field of ultrasound-responsive prodrug systems exploits the mechanical and chemical effects of ultrasonication for the controlled activation of prodrugs. In polymer mechanochemistry, materials scientists exploit the sonomechanical effect of acoustic cavitation to mechanochemically activate force-sensitive prodrugs. On the other hand, researchers in the field of sonodynamic therapy adopt fundamentally distinct methodologies, utilizing the sonochemical effect (e.g., generation of reactive oxygen species) of ultrasound in the presence of sonosensitizers to induce chemical transformations that activate prodrugs. This cross-disciplinary review comprehensively examines these two divergent yet interrelated approaches, both of which originated from acoustic cavitation. It highlights molecular and materials design strategies and potential applications in diverse therapeutic contexts, from chemotherapy to immunotherapy and gene therapy methods, and discusses future directions in this rapidly advancing domain.
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Affiliation(s)
- Xuancheng Fu
- Department of Chemistry, BioInspired Institute, Syracuse University, Syracuse, New York 13244, United States
| | - Xiaoran Hu
- Department of Chemistry, BioInspired Institute, Syracuse University, Syracuse, New York 13244, United States
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3
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Wang H, Benter S, Dononelli W, Neudecker T. JEDI: A versatile code for strain analysis of molecular and periodic systems under deformation. J Chem Phys 2024; 160:152501. [PMID: 38639312 DOI: 10.1063/5.0199247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/07/2024] [Indexed: 04/20/2024] Open
Abstract
Stretching or compression can induce significant energetic, geometric, and spectroscopic changes in materials. To fully exploit these effects in the design of mechano- or piezo-chromic materials, self-healing polymers, and other mechanoresponsive devices, a detailed knowledge about the distribution of mechanical strain in the material is essential. Within the past decade, Judgement of Energy DIstribution (JEDI) analysis has emerged as a useful tool for this purpose. Based on the harmonic approximation, the strain energy in each bond length, bond angle, and dihedral angle of the deformed system is calculated using quantum chemical methods. This allows the identification of the force-bearing scaffold of the system, leading to an understanding of mechanochemical processes at the most fundamental level. Here, we present a publicly available code that generalizes the JEDI analysis, which has previously only been available for isolated molecules. Now, the code has been extended to two- and three-dimensional periodic systems, supramolecular clusters, and substructures of chemical systems under various types of deformation. Due to the implementation of JEDI into the Atomic Simulation Environment, the JEDI analysis can be interfaced with a plethora of program packages that allow the calculation of electronic energies for molecular systems and systems with periodic boundary conditions. The automated generation of a color-coded three-dimensional structure via the Visual Molecular Dynamics program allows insightful visual analyses of the force-bearing scaffold of the strained system.
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Affiliation(s)
- Henry Wang
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany
| | - Sanna Benter
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany
| | - Wilke Dononelli
- Hybrid Materials Interfaces Group, Am Fallturm 1, D-28359 Bremen, Germany
- Bremen Center for Computational Materials Science, Am Fallturm 1, D-28359 Bremen, Germany
- MAPEX Center for Materials and Processes, Bibliothekstraße 1, D-28359 Bremen, Germany
| | - Tim Neudecker
- University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Straße 6, D-28359 Bremen, Germany
- Bremen Center for Computational Materials Science, Am Fallturm 1, D-28359 Bremen, Germany
- MAPEX Center for Materials and Processes, Bibliothekstraße 1, D-28359 Bremen, Germany
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4
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Sun Y, Neary WJ, Huang X, Kouznetsova TB, Ouchi T, Kevlishvili I, Wang K, Chen Y, Kulik HJ, Craig SL, Moore JS. A Thermally Stable SO 2-Releasing Mechanophore: Facile Activation, Single-Event Spectroscopy, and Molecular Dynamic Simulations. J Am Chem Soc 2024; 146:10943-10952. [PMID: 38581383 DOI: 10.1021/jacs.4c02139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2024]
Abstract
Polymers that release small molecules in response to mechanical force are promising candidates as next-generation on-demand delivery systems. Despite advancements in the development of mechanophores for releasing diverse payloads through careful molecular design, the availability of scaffolds capable of discharging biomedically significant cargos in substantial quantities remains scarce. In this report, we detail a nonscissile mechanophore built from an 8-thiabicyclo[3.2.1]octane 8,8-dioxide (TBO) motif that releases one equivalent of sulfur dioxide (SO2) from each repeat unit. The TBO mechanophore exhibits high thermal stability but is activated mechanochemically using solution ultrasonication in either organic solvent or aqueous media with up to 63% efficiency, equating to 206 molecules of SO2 released per 143.3 kDa chain. We quantified the mechanochemical reactivity of TBO by single-molecule force spectroscopy and resolved its single-event activation. The force-coupled rate constant for TBO opening reaches ∼9.0 s-1 at ∼1520 pN, and each reaction of a single TBO domain releases a stored length of ∼0.68 nm. We investigated the mechanism of TBO activation using ab initio steered molecular dynamic simulations and rationalized the observed stereoselectivity. These comprehensive studies of the TBO mechanophore provide a mechanically coupled mechanism of multi-SO2 release from one polymer chain, facilitating the translation of polymer mechanochemistry to potential biomedical applications.
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Affiliation(s)
- Yunyan Sun
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - William J Neary
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Xiao Huang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Tatiana B Kouznetsova
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Tetsu Ouchi
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Ilia Kevlishvili
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Kecheng Wang
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Yingying Chen
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Department of Material Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Heather J Kulik
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Stephen L Craig
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Jeffrey S Moore
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
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5
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Abstract
Force-controlled release of small molecules offers great promise for the delivery of drugs and the release of healing or reporting agents in a medical or materials context1-3. In polymer mechanochemistry, polymers are used as actuators to stretch mechanosensitive molecules (mechanophores)4. This technique has enabled the release of molecular cargo by rearrangement, as a direct5,6 or indirect7-10 consequence of bond scission in a mechanophore, or by dissociation of cage11, supramolecular12 or metal complexes13,14, and even by 'flex activation'15,16. However, the systems described so far are limited in the diversity and/or quantity of the molecules released per stretching event1,2. This is due to the difficulty in iteratively activating scissile mechanophores, as the actuating polymers will dissociate after the first activation. Physical encapsulation strategies can be used to deliver a larger cargo load, but these are often subject to non-specific (that is, non-mechanical) release3. Here we show that a rotaxane (an interlocked molecule in which a macrocycle is trapped on a stoppered axle) acts as an efficient actuator to trigger the release of cargo molecules appended to its axle. The release of up to five cargo molecules per rotaxane actuator was demonstrated in solution, by ultrasonication, and in bulk, by compression, achieving a release efficiency of up to 71% and 30%, respectively, which places this rotaxane device among the most efficient release systems achieved so far1. We also demonstrate the release of three representative functional molecules (a drug, a fluorescent tag and an organocatalyst), and we anticipate that a large variety of cargo molecules could be released with this device. This rotaxane actuator provides a versatile platform for various force-controlled release applications.
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Affiliation(s)
- Lei Chen
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Robert Nixon
- Department of Chemistry, University of Manchester, Manchester, UK
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Manchester, UK.
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6
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Zeng T, Ordner LA, Liu P, Robb MJ. Multimechanophore Polymers for Mechanically Triggered Small Molecule Release with Ultrahigh Payload Capacity. J Am Chem Soc 2024; 146:95-100. [PMID: 38157405 PMCID: PMC10786027 DOI: 10.1021/jacs.3c11927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/16/2023] [Accepted: 12/26/2023] [Indexed: 01/03/2024]
Abstract
Polymers that release small molecules in response to mechanical force are promising for a variety of applications including drug delivery, catalysis, and sensing. While a number of mechanophores have been developed for the release of covalently bound payloads, existing strategies are either limited in cargo scope or, in the case of more general mechanophore designs, are restricted to the release of one or two cargo molecules per polymer chain. Herein, we introduce a nonscissile mechanophore based on a masked 2-furylcarbinol derivative that enables the preparation of multimechanophore polymers with ultrahigh payload capacity. We demonstrate that polymers prepared via ring-opening metathesis polymerization are capable of releasing hundreds of small-molecule payloads per polymer chain upon ultrasound-induced mechanochemical activation. This nonscissile masked 2-furylcarbinol mechanophore overcomes a major challenge in cargo loading capacity associated with previous 2-furylcarbinol mechanophore designs, enabling applications that benefit from much higher concentrations of delivered cargo.
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Affiliation(s)
- Tian Zeng
- Division of Chemistry and
Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
| | - Liam A. Ordner
- Division of Chemistry and
Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
| | - Peng Liu
- Division of Chemistry and
Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
| | - Maxwell J. Robb
- Division of Chemistry and
Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
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7
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Chang HC, Liang MC, Luc VS, Davis C, Chang CC. Mechanochemical Reactivity of a 1,2,4-Triazoline-3,5-dione-Anthracene Diels-Alder Adduct. Chem Asian J 2024; 19:e202300850. [PMID: 37938167 DOI: 10.1002/asia.202300850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 10/31/2023] [Accepted: 11/05/2023] [Indexed: 11/09/2023]
Abstract
Force-responsive molecules that produce fluorescent moieties under stress provide a means for stress-sensing and material damage assessment. In this work, we report a mechanophore based on Diels-Alder adduct TAD-An of 4,4'-(4,4'-diphenylmethylene)-bis-(1,2,4-triazoline-3,5-dione) and initiator-substituted anthracene that can undergo retro-Diels-Alder (rDA) reaction by pulsed ultrasonication and compressive activation in bulk materials. The influence of having C-N versus C-C bonds at the sites of bond scission is elucidated by comparing the relative mechanical strength of TAD-An to another Diels-Alder adduct MAL-An obtained from maleimide and anthracene. The susceptibility to undergo rDa reaction correlates well with bond energy, such that C-N bond containing TAD-An degrades faster C-C bond containing MAL-An because C-N bond is weaker than C-C bond. Specifically, the results from polymer degradation kinetics under pulsed ultrasonication shows that polymer containing TAD-An has a rate constant of 1.59×10-5 min-1 , while MAL-An (C-C bond) has a rate constant of 1.40×10-5 min-1 . Incorporation of TAD-An in a crosslinked polymer network demonstrates the feasibility to utilize TAD-An as an alternative force-responsive probe to visualize mechanical damage where fluorescence can be "turned-on" due to force-accelerated retro-Diels-Alder reaction.
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Affiliation(s)
- Hao-Chun Chang
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu, Taiwan, No. 1001, Daxue Rd. East Dist., Hsinchu City, 300093, Taiwan
- Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu, 300093, Taiwan
| | - Min-Chieh Liang
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu, Taiwan, No. 1001, Daxue Rd. East Dist., Hsinchu City, 300093, Taiwan
- Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu, 300093, Taiwan
| | - Van-Sieu Luc
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu, Taiwan, No. 1001, Daxue Rd. East Dist., Hsinchu City, 300093, Taiwan
- Sustainable Chemical Science and Technology (SCST), Taiwan International Graduate Program (TIGP), Academia Sinica, Taipei, 11529, Taiwan
- Institute of Chemistry, Academia Sinica, Taipei, 11529, Taiwan
| | - Chelsea Davis
- Department of Mechanical Engineering, University of Delaware, Newark, Delaware, 19716, U.S.A
| | - Chia-Chih Chang
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu, Taiwan, No. 1001, Daxue Rd. East Dist., Hsinchu City, 300093, Taiwan
- Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu, 300093, Taiwan
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8
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Izak-Nau E, Niggemann LP, Göstl R. Brownian Relaxation Shakes and Breaks Magnetic Iron Oxide-Polymer Nanocomposites to Release Cargo. Small 2024; 20:e2304527. [PMID: 37715071 DOI: 10.1002/smll.202304527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/31/2023] [Indexed: 09/17/2023]
Abstract
Magnetic nanoparticles (NPs) are widely employed for remote controlled molecular release applications using alternating magnetic fields (AMF). Yet, they intrinsically generate heat in the process by Néel relaxation limiting their application scope. In contrast, iron oxide NPs larger than ≈15 nm react to AMF by Brownian relaxation resulting in tumbling and shaking. Here, such iron oxide NPs are combined with polymer shells where the shaking motion mechanically agitates and partially detaches the polymer chains, covalently cleaves a fraction of the polymers, and releases the prototypical cargo molecules doxorubicin and curcumin into solution. This heat-free release mechanism broadens the potential application space of polymer-functionalized magnetic NP composites.
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Affiliation(s)
- Emilia Izak-Nau
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52056, Aachen, Germany
| | - Louisa P Niggemann
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52056, Aachen, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074, Aachen, Germany
| | - Robert Göstl
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52056, Aachen, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074, Aachen, Germany
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9
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Nieland E, Voss J, Schmidt BM. Photoresponsive Supramolecular Cages and Macrocycles. Chempluschem 2023; 88:e202300353. [PMID: 37638597 DOI: 10.1002/cplu.202300353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 08/27/2023] [Accepted: 08/28/2023] [Indexed: 08/29/2023]
Abstract
The utilisation of light to achieve precise manipulation and control over the structure and function of supramolecular assemblies has emerged as a highly promising approach in the development of complex, configurable, or multifunctional systems and nanoscopic machine-like entities. In this minireview, we highlight recent examples of self-assembled and covalently bound cages and macrocycles with a focus on the external and internal functionalisation of a structure with a photoswitchable unit or the embedment of a photoswitch into the framework of a structure. Functionalising the interior or exterior of a supramolecular cage or macrocycle with a photoresponsive group enables control over different properties, such as guest binding or assembly in the solid-state, while the overall shape of the assembly often undergoes no significant change. By directly integrating a photoswitchable unit into the framework of a supramolecular structure, the isomerisation can either induce a geometry change, the disassembly, or the disassembly and reassembly of the structure. Historical and recent examples covered in this review are based on azobenzene, diarylethene, stilbene photoswitches, or alkene motors that were incorporated into macrocycles and cages constructed by metal-organic, dynamic covalent, or covalent bonds.
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Affiliation(s)
- Esther Nieland
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Jona Voss
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Bernd M Schmidt
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
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10
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He X, Tian Y, O’Neill RT, Xu Y, Lin Y, Weng W, Boulatov R. Coumarin Dimer Is an Effective Photomechanochemical AND Gate for Small-Molecule Release. J Am Chem Soc 2023; 145:23214-23226. [PMID: 37821455 PMCID: PMC10603814 DOI: 10.1021/jacs.3c07883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Indexed: 10/13/2023]
Abstract
Stimulus-responsive gating of chemical reactions is of considerable practical and conceptual interest. For example, photocleavable protective groups and gating mechanophores allow the kinetics of purely thermally activated reactions to be controlled optically or by mechanical load by inducing the release of small-molecule reactants. Such release only in response to a sequential application of both stimuli (photomechanochemical gating) has not been demonstrated despite its unique expected benefits. Here, we describe computational and experimental evidence that coumarin dimers are highly promising moieties for realizing photomechanochemical control of small-molecule release. Such dimers are transparent and photochemically inert at wavelengths >300 nm but can be made to dissociate rapidly under tensile force. The resulting coumarins are mechanochemically and thermally stable, but rapidly release their payload upon irradiation. Our DFT calculations reveal that both strain-free and mechanochemical kinetics of dimer dissociation are highly tunable over an unusually broad range of rates by simple substitution. In head-to-head dimers, the phenyl groups act as molecular levers to allow systematic and predictable variation in the force sensitivity of the dissociation barriers by choice of the pulling axis. As a proof-of-concept, we synthesized and characterized the reactivity of one such dimer for photomechanochemically controlled release of aniline and its application for controlling bulk gelation.
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Affiliation(s)
- Xiaojun He
- Department
of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Yancong Tian
- Department
of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, U.K.
| | - Robert T. O’Neill
- Department
of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, U.K.
| | - Yuanze Xu
- Department
of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Yangju Lin
- Department
of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Wengui Weng
- Department
of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Roman Boulatov
- Department
of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, U.K.
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11
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Abstract
Mechanophores (mechanosensitive molecules) have been instrumental in the development of various force-controlled release systems. However, the release of functional organic molecules is often the consequence of a secondary (nonmechanical) process triggered by an initial bond scission. Here we present a new mechanophore, built around an oxanorbornane-triazoline core, that is able to release a furan molecule following a force-promoted double retro-[4+2][3+2] cycloaddition. We explored this unprecedented transformation experimentally (sonication) and computationally (DFT, CoGEF) and found that the observed reactivity is controlled by the geometry of the adduct, as this reaction pathway is only accessible to the endo-exo-cis isomer. These results further demonstrate the unique reactivity of molecules under tension and offer a new mechanism for the force-controlled release of small molecules.
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Affiliation(s)
- Kamil Suwada
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
| | - Alice Weng Ieong
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
| | - Hei Lok Herman Lo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
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12
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Noh J, Koo MB, Jung J, Peterson GI, Kim KT, Choi TL. Monodisperse Cyclic Polymer Mechanochemistry: Scission Kinetics and the Dynamic Memory Effect with Ultrasonication and Ball-Mill Grinding. J Am Chem Soc 2023; 145:18432-18438. [PMID: 37486970 DOI: 10.1021/jacs.3c04733] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/26/2023]
Abstract
A series of monodisperse cyclic and linear poly(d,l-lactide)s (c-PLA and l-PLA, respectively) were prepared with various degrees of polymerization (DP) using an iterative convergent synthesis approach. The absence of a molecular weight distribution provided us a chance to study their mechanochemical reactivity without obstructions arising from the size distribution. Additionally, we prepared l- and c-PLAs with identical DPs, which enabled us to attribute differences in scission rates to the cyclic polymer architecture alone. The polymers were subjected to ultrasonication (US) and ball-mill grinding (BMG), and their degradation kinetics were explored. Up to 9.0 times larger scission rates were observed for l-PLA (compared to c-PLA) with US, but the difference was less than 1.9 times with BMG. Fragmentation requires two backbone scission events for c-PLA, and we were able to observe linear intermediates (formed after a single scission) for the first time. We also developed a new method of studying the dynamic memory effect in US by characterizing and comparing the daughter fragment molecular weight distributions of l- and c-PLAs. These results provide new insights into the influence of the cyclic polymer architecture on mechanochemical reactions as well as differences in reactivity observed with US and BMG.
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Affiliation(s)
- Jinkyung Noh
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Mo Beom Koo
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Jisoo Jung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Gregory I Peterson
- Department of Chemistry and Research Institute of Basic Science, Incheon National University, Incheon 22012, Republic of Korea
| | - Kyoung Taek Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Tae-Lim Choi
- Department of Materials, ETH Zürich, Zürich 8093, Switzerland
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13
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Das A, Datta A. Designing Site Specificity in the Mechanochemical Cargo Release of Small Molecules. J Am Chem Soc 2023. [PMID: 37291056 DOI: 10.1021/jacs.3c05116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Mechanical force can trigger the predictable and precise release of small molecules from macromolecular carriers. In this article, based on mechanochemical simulations, we show that norborn-2-en-7-one (NEO), I, and its derivatives can selectively release CO, N2, and SO2 and produce two distinctly different products, A ((3E,5Z,7E)-dimethyl-5,6-diphenyldeca-3,5,7-triene-1,10-diyl bis(2-bromo-2-methylpropanoate)) and B (4',5'-dimethyl-4',5'-dihydro-[1,1':2',1''-terphenyl]-3',6'-diyl)bis(ethane-2,1-diyl) bis(2-bromo-2-methylpropanoate). Site-specific design in the pulling points (PP) ensures that by changing the regioselectivity, either A or B can be exclusively generated. Controlling the rigidity of the NEO scaffold by replacing a 6-membered ring with an 8-membered ring and concomitantly tuning the pulling groups makes it mechanolabile toward the selective formation of B. The diradical intermediate formed during I → A is predicted to be persistent for ∼150 fs. The structural design holds the key to the trade-off between mechanochemical rigidity and lability.
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Affiliation(s)
- Ankita Das
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, West Bengal, India
| | - Ayan Datta
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, West Bengal, India
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14
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Küng R, Germann A, Krüsmann M, Niggemann LP, Meisner J, Karg M, Göstl R, Schmidt BM. Mechanoresponsive Metal-Organic Cage-Crosslinked Polymer Hydrogels. Chemistry 2023; 29:e202300079. [PMID: 36715238 DOI: 10.1002/chem.202300079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 01/28/2023] [Accepted: 01/30/2023] [Indexed: 01/31/2023]
Abstract
We report the formation of metal-organic cage-crosslinked polymer hydrogels. To enable crosslinking of the cages and subsequent network formation, we used homodifunctionalized poly(ethylene glycol) (PEG) chains terminally substituted with bipyridines as ligands for the Pd6 L4 corners. The encapsulation of guest molecules into supramolecular self-assembled metal-organic cage-crosslinked hydrogels, as well as ultrasound-induced disassembly of the cages with release of their cargo, is presented in addition to their characterization by nuclear magnetic resonance (NMR) techniques, rheology, and comprehensive small-angle X-ray scattering (SAXS) experiments. The constrained geometries simulating external force (CoGEF) method and barriers using a force-modified potential energy surface (FMPES) suggest that the cage-opening mechanism starts with the dissociation of one pyridine ligand at around 0.5 nN. We show the efficient sonochemical activation of the hydrogels HG3 -6 , increasing the non-covalent guest-loading of completely unmodified drugs available for release by a factor of ten in comparison to non-crosslinked, star-shaped assemblies in solution.
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Affiliation(s)
- Robin Küng
- Institute for Organic Chemistry and Macromolecular Chemistry, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - Anne Germann
- Institute for Organic Chemistry and Macromolecular Chemistry, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - Marcel Krüsmann
- Institute for Physical Chemistry I: Colloids and Nanooptics, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - Louisa P Niggemann
- DWI - Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52056, Aachen, Germany.,Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Jan Meisner
- Institute for Physical Chemistry, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - Matthias Karg
- Institute for Physical Chemistry I: Colloids and Nanooptics, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - Robert Göstl
- DWI - Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52056, Aachen, Germany
| | - Bernd M Schmidt
- Institute for Organic Chemistry and Macromolecular Chemistry, Heinrich Heine University Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
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15
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Abstract
Block copolymers (BCPs) are used in numerous applications in modern materials science. Yet, like homopolymers, BCPs can undergo covalent bond scission when mechanically stressed (mechanochemistry), which could lead to unexpected consequences in such applications. BCPs' heterogeneity may affect force transduction, perhaps changing force distribution and localization. To verify this, a gem-dichlorocyclopropane (gDCC) embedded linear chain is prepared and extended with a poly(methyl methacrylate) block. When stressed in solution, the mechanochemical ring-opening of gDCC is accelerated compared to homopolymers, even though the mechanophores are at the chain ends. Moreover, a higher mechanophore activation selectivity is obtained. These results indicate that mechanochemical response outside, and even far from the chain center is quite prominent in BCPs, and that forces along the polymer chain can efficiently activate multi-mechanophores regions, even when far from the polymer midchain.
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Affiliation(s)
- Hang Zhang
- Schulich Faculty of Chemistry, Technion-, Israel Institute of Technology, Haifa, 3200008, Israel
| | - Charles E Diesendruck
- Schulich Faculty of Chemistry, Technion-, Israel Institute of Technology, Haifa, 3200008, Israel
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16
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Luo SM, Barber RW, Overholts AC, Robb MJ. Competitive Activation Experiments Reveal Significantly Different Mechanochemical Reactivity of Furan–Maleimide and Anthracene–Maleimide Mechanophores. ACS Polym Au 2022; 3:202-208. [PMID: 37065719 PMCID: PMC10103189 DOI: 10.1021/acspolymersau.2c00047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/01/2022] [Accepted: 11/01/2022] [Indexed: 11/23/2022]
Abstract
During the past two decades, our understanding of mechanochemical reactivity has advanced considerably. Nevertheless, an incomplete knowledge of structure-activity relationships and the principles that govern mechanochemical transformations limits molecular design. The experimental development of mechanophores has thus benefited from simple computational tools like CoGEF, from which quantitative metrics like rupture force can be extracted to estimate reactivity. Furan-maleimide (FM) and anthracene-maleimide (AM) Diels-Alder adducts are widely studied mechanophores that undergo retro-Diels-Alder reactions upon mechanical activation in polymers. Despite possessing significantly different thermal stability, similar rupture forces predicted by CoGEF calculations suggest that these compounds exhibit similar mechanochemical reactivity. Here, we directly probe the relative mechanochemical reactivity of FM and AM adducts through competitive activation experiments. Ultrasound-induced mechanochemical activation of bis-adduct mechanophores comprising covalently tethered FM and AM subunits reveals pronounced selectivity-as high as ∼13:1-for reaction of the FM adduct compared to the AM adduct. Computational models provide insight into the greater reactivity of the FM mechanophore, indicating a more efficient mechanochemical coupling for the FM adduct compared to the AM adduct. The methodology employed here to directly interrogate the relative reactivity of two different mechanophores using a tethered bis-adduct configuration may be useful for other systems where more common sonication-based approaches are limited by poor sensitivity.
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Affiliation(s)
- Stella M. Luo
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Ross W. Barber
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Anna C. Overholts
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Maxwell J. Robb
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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17
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Campagna D, Göstl R. Mechanoresponsive Carbamoyloximes for the Activation of Secondary Amines in Polymers. Angew Chem Int Ed Engl 2022; 61:e202207557. [PMID: 35905139 DOI: 10.1002/anie.202207557] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Indexed: 01/07/2023]
Abstract
Mechanophores are molecular moieties that are incorporated into polymers and respond to force with constitutional, configurational, or conformational bond rearrangements to enable functionality. Up to today, several chemically latent motifs have been activated by polymer mechanochemical methods, but the generation of secondary amines remains elusive. Here we report carbamoyloximes as mechanochemical protecting groups for secondary amines. We show that carbamoyloximes undergo force-induced homolytic bond scission at the N-O oxime bond in polymers thus producing the free amine, as the reaction proceeds via the carbamoyloxyl and aminyl radicals, analogously to its photochemical counterpart. Eventually, we apply the carbamoyloxime motif in a force-activated organocatalytic Knoevenagel reaction. We believe that this protecting strategy can be universally applied for many other secondary and primary amines in polymer materials.
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Affiliation(s)
- Davide Campagna
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52056, Aachen, Germany.,Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Robert Göstl
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52056, Aachen, Germany
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18
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Abstract
The formation and scission of chemical bonds facilitated by mechanical force (mechanochemistry) can be accomplished through various experimental strategies. Among them, ultrasonication of polymeric matrices and ball milling of reaction partners have become the two leading approaches to carry out polymer and small molecule mechanochemistry, respectively. Often, the methodological differences between these practical strategies seem to have created two seemingly distinct lines of thought within the field of mechanochemistry. However, in this Perspective article, the reader will encounter a series of studies in which some aspects believed to be inherently related to either polymer or small molecule mechanochemistry sometimes overlap, evidencing the connection between both approaches.
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Affiliation(s)
- José G Hernández
- Grupo Ciencia de los Materiales, Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia, Calle 70 No 52-21, Medellín, Colombia
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19
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Klok HA, Herrmann A, Göstl R. Force ahead: Emerging Applications and Opportunities of Polymer Mechanochemistry. ACS Polym Au 2022; 2:208-212. [PMID: 35971420 PMCID: PMC9372995 DOI: 10.1021/acspolymersau.2c00029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Harm-Anton Klok
- Institut des Matériaux and Institut des Sciences et Ingénierie Chimiques, Laboratoire des Polymères, École Polytechnique Fédérale de Lausanne (EPFL), Station 12, CH-1015 Lausanne, Switzerland
| | - Andreas Herrmann
- DWI − Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52056 Aachen, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Robert Göstl
- DWI − Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, 52056 Aachen, Germany
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20
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Campagna D, Göstl R. Mechanoresponsive Carbamoyloximes for the Activation of Secondary Amines in Polymers. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202207557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Davide Campagna
- DWI - Leibniz Institute for Interactive Materials Mechanoresponsive (bio)materials Forckenbeckstr. 50 52056 Aachen GERMANY
| | - Robert Göstl
- DWI-Leibniz-Institut für Interaktive Materialien: DWI-Leibniz-Institut fur Interaktive Materialien Mechanoresponsive (bio)materials Forckenbeckstr. 50 52056 Aachen GERMANY
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21
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Abstract
The field of force-induced release of small cargoes within polymeric materials has experienced rapid growth over the past decade, not only including achieving diversified functional materials that report force, trigger degradation, activate drugs and release catalysts, but also involving investigations on the interesting force-coupled reactivity of mechanophores, such as ferrocenes. In this highlight article, we review the recent progress on polymer mechanochemistry that releases small cargoes, including small molecules and metal ions. Since mechanophores play a key role in force-responsive materials, we introduce the progress by discussing different types of mechanophores and their mechanochemical reactions for the release of acids, gases, fluorophores, drugs, iron ions, and so on. At the end, we provide our perspectives on the remaining challenges and future targets in this growing field.
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Affiliation(s)
- Hang Shen
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China.
| | - Yunzheng Cao
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China.
| | - Miaojiang Lv
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China.
| | - Qinxin Sheng
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China.
| | - Zhengbiao Zhang
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China. .,State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, China
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22
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Affiliation(s)
- Miancheng Zou
- DWI – Leibniz Institute for Interactive Materials Aachen Germany
- Zernike Institute for Advanced Materials University of Groningen Groningen AG
| | - Pengkun Zhao
- DWI – Leibniz Institute for Interactive Materials Aachen Germany
- Zernike Institute for Advanced Materials University of Groningen Groningen AG
| | - Jilin Fan
- DWI – Leibniz Institute for Interactive Materials Aachen Germany
- Institute of Technical and Macromolecular Chemistry RWTH Aachen University Aachen Germany
| | - Robert Göstl
- DWI – Leibniz Institute for Interactive Materials Aachen Germany
| | - Andreas Herrmann
- DWI – Leibniz Institute for Interactive Materials Aachen Germany
- Zernike Institute for Advanced Materials University of Groningen Groningen AG
- Institute of Technical and Macromolecular Chemistry RWTH Aachen University Aachen Germany
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23
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Sun Y, Neary WJ, Burke ZP, Qian H, Zhu L, Moore JS. Mechanically Triggered Carbon Monoxide Release with Turn-On Aggregation-Induced Emission. J Am Chem Soc 2022; 144:1125-1129. [PMID: 35019277 DOI: 10.1021/jacs.1c12108] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Polymers that release functional small molecules under mechanical stress potentially serve as next-generation materials for catalysis, sensing, and mechanochemical dynamic therapy. To further expand the function of mechanoresponsive materials, the discovery of chemistries capable of small molecule release are highly desirable. In this report, we detail a nonscissile bifunctional mechanophore (i.e., dual mechano-activated properties) based on a unique mechanochemical reaction involving norborn-2-en-7-one (NEO). One property is the release of carbon monoxide (CO) upon pulsed solution ultrasonication. A release efficiency of 58% is observed at high molecular weights (Mn = 158.8 kDa), equating to ∼154 molecules of CO released per chain. The second property is the bright cyan emission from the macromolecular product in its aggregated state, resulting in a turn-on fluorescence readout coincident with CO release. This report not only demonstrates a unique strategy for the release of small molecules in a nonscissile way but also guides future designs of force-responsive aggregation-induced emission (AIE) luminogens.
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Affiliation(s)
- Yunyan Sun
- Department of Chemistry, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
| | - William J Neary
- Department of Chemistry, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States.,Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
| | - Zachary P Burke
- Department of Chemistry, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
| | - Hai Qian
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
| | - Lingyang Zhu
- Department of Chemistry, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
| | - Jeffrey S Moore
- Department of Chemistry, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States.,Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
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