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Gillhuber S, Holloway JO, Mundsinger K, Kammerer JA, Harmer JR, Frisch H, Barner-Kowollik C, Roesky PW. Visible light photoflow synthesis of a Cu(ii) single-chain polymer nanoparticle catalyst. Chem Sci 2024:d4sc03079f. [PMID: 39246378 PMCID: PMC11376198 DOI: 10.1039/d4sc03079f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Accepted: 08/14/2024] [Indexed: 09/10/2024] Open
Abstract
We herein pioneer the visible light (λ max = 410 nm) mediated flow synthesis of catalytically active single-chain nanoparticles (SCNPs). Our design approach is based on a copolymer of poly(ethylene glycol) methyl ether methacrylate and a photocleavable 2-((((2-nitrobenzyl)oxy)carbonyl)amino)ethyl methacrylate monomer which can liberate amine groups upon visible light irradiation, allowing for single-chain collapse via the complexation of Cu(ii) ions. We initially demonstrate the successful applicability of our design approach for the batch photochemical synthesis of Cu(ii) SCNPs and transfer the concept to photoflow conditions, enabling, for the first time, the continuous production of functional SCNPs. Critically, we explore their ability to function as a photocatalyst for the cleavage of carbon-carbon single and double bonds on the examples of xanthene-9-carboxylic acid and oleic acid, demonstrating the advantageous effect SCNPs can provide over analogous small molecule catalysts.
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Affiliation(s)
- Sebastian Gillhuber
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT) Engesserstraße 15 76131 Karlsruhe Germany
- School of Chemistry and Physics, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
- Centre for Materials Science, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
| | - Joshua O Holloway
- School of Chemistry and Physics, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
- Centre for Materials Science, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
| | - Kai Mundsinger
- School of Chemistry and Physics, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
- Centre for Materials Science, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
| | - Jochen A Kammerer
- School of Chemistry and Physics, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
- Centre for Materials Science, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
| | - Jeffrey R Harmer
- Centre for Advanced Imaging, The University of Queensland (UQ) Building 57 Research Road 4072 Brisbane QLD Australia
| | - Hendrik Frisch
- School of Chemistry and Physics, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
- Centre for Materials Science, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
| | - Christopher Barner-Kowollik
- School of Chemistry and Physics, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
- Centre for Materials Science, Queensland University of Technology (QUT) 2 George Street 4000 Brisbane QLD Australia
- Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT) Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
| | - Peter W Roesky
- Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT) Engesserstraße 15 76131 Karlsruhe Germany
- Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT) Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
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2
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Wang Y, Wang H, Lu B, Yu K, Xie R, Lan G, Xie J, Hu E, Lu F. A sandwich-like silk fibroin/polysaccharide composite dressing with continual biofluid draining for wound exudate management. Int J Biol Macromol 2023; 253:127000. [PMID: 37739294 DOI: 10.1016/j.ijbiomac.2023.127000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 09/06/2023] [Accepted: 09/17/2023] [Indexed: 09/24/2023]
Abstract
Optimal wound healing requires a wet microenvironment without over-hydration. Inspired by capillarity and transpiration, we have developed a sandwich-like fibers/sponge dressing with continuous exudate drainage to maintain appropriate wound moisture. This dressing is prepared by integrating a three-layer structure using the freeze-drying method. Layer I, as the side that contacts with the skin directly, consists of a hydrophobic silk fibroin membrane; Layer II, providing the pumping action, is made of superabsorbent chitosan-konjac glucomannan sponge; Layer III, accelerating evaporation sixfold compared to natural evaporation, is constructed with a graphene oxide soaked hydrophilic cellulose acetate membrane. Animal experiments showed that the composite dressing had superior wound-healing characteristics, with wounds decreasing to 24.8% of their original size compared to 28.5% for the commercial dressing and 43.2% for the control. The enhanced wound healing can be ascribed to the hierarchical porous structure serves as the fluid-driving factor in this effort; the hydrophilicity of a membrane composed of silk fibroin nanofibers is adjustable to regulate fluid-transporting capacity; and the photothermal effect of graphene oxide guarantees exudates that have migrated to the top layer to evaporate continuously. These findings indicate the unidirectional wicking dressing has the potential to become the next generation of clinical dressings.
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Affiliation(s)
- Yixin Wang
- State Key Laboratory of Resource Insects, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Biomaterial Fiber and Modern Textile, Chongqing 400715, China
| | - Haoyu Wang
- State Key Laboratory of Resource Insects, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Biomaterial Fiber and Modern Textile, Chongqing 400715, China
| | - Bitao Lu
- State Key Laboratory of Resource Insects, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Biomaterial Fiber and Modern Textile, Chongqing 400715, China
| | - Kun Yu
- State Key Laboratory of Resource Insects, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Biomaterial Fiber and Modern Textile, Chongqing 400715, China
| | - Ruiqi Xie
- State Key Laboratory of Resource Insects, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Biomaterial Fiber and Modern Textile, Chongqing 400715, China
| | - Guangqian Lan
- State Key Laboratory of Resource Insects, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Biomaterial Fiber and Modern Textile, Chongqing 400715, China
| | - Jing Xie
- Department of Stomatology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China.
| | - Enling Hu
- State Key Laboratory of Resource Insects, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China; School of Fashion and Textiles, The Hong Kong Polytechnic University, Kowloon, Hong Kong.
| | - Fei Lu
- State Key Laboratory of Resource Insects, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Biomaterial Fiber and Modern Textile, Chongqing 400715, China.
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3
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Oh XY, Nguyen TM, Ye E, Luo HK, Singh PND, Loh XJ, Truong VX. Visible Light Degradable Acridine-Containing Polyurethanes in an Aqueous Environment. ACS Macro Lett 2023:690-696. [PMID: 37172115 DOI: 10.1021/acsmacrolett.3c00158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Light degradable polymers hold significant promise in a wide range of applications including the fabrication of optically recyclable materials, responsive coatings and adhesives, and controlled drug delivery. Here, we report the synthesis of polyurethanes that can be degraded under irradiation of visible light (≤450 nm) from commercial LED (3-15 W) light sources. The photolysis occurs in an aqueous environment via photocleavage of an acridine moiety incorporated within the backbone of the polymer chains. Analysis of the quantum yield as a function of wavelength reveals highly efficient photoreactivity at up to 440 nm activation, which is red-shifted compared to the UV-vis absorbance of the chromophore. The potential of our chemical system in biomaterials is demonstrated by the fabrication of an in situ forming hydrogel that can be degraded by visible light.
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Affiliation(s)
- Xin Yi Oh
- Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore 138634, Republic of Singapore
| | - Tuan Minh Nguyen
- Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, Singapore 627833, Republic of Singapore
| | - Enyi Ye
- Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore 138634, Republic of Singapore
| | - He-Kuan Luo
- Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, Singapore 627833, Republic of Singapore
| | - Pradeep N D Singh
- Department of Chemistry, Indian Institute of Technology (IIT), Kharagpur, West Bengal 721302, India
| | - Xian Jun Loh
- Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore 138634, Republic of Singapore
- Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, Singapore 627833, Republic of Singapore
| | - Vinh Xuan Truong
- Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, Singapore 627833, Republic of Singapore
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4
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Potential of Advanced Oxidation as Pretreatment for Microplastics Biodegradation. SEPARATIONS 2023. [DOI: 10.3390/separations10020132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
In the last two decades, microplastics (MP) have been identified as an emerging environmental pollutant. Due to their small size, MP particles may easily enter the food chain, where they can have adverse effects on organisms and the environment in general. The common methods for the removal of pollutants from the environment are not fully effective in the elimination of MP; thus, it is necessary to find a more suitable treatment method(s). Among the various approaches tested, biodegradation is by far the most environmentally friendly and economically acceptable remediation approach. However, it has serious drawbacks, generally related to the rather low removal rate and often insufficient efficiency. Therefore, it would be beneficial to use some of the less economical but more efficient methods as pretreatment prior to biodegradation. Such pretreatment would primarily serve to increase the roughness and hydrophilicity of the surface of MP, making it more susceptible to bioassimilation. This review focuses on advanced oxidation processes (AOPs) as treatment methods that can enhance the biodegradation of MP particles. It considers MP particles of the six most commonly used plastic polymers, namely: polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyethylene terephthalate and polyurethane. The review highlights organisms with a high potential for biodegradation of selected MP particles and presents the potential benefits that AOP pretreatment can provide for MP biodegradation.
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Kubota H, Ouchi M. Rapid and Selective Photo-degradation of Polymers: Design of an Alternating Copolymer with an o-Nitrobenzyl Ether Pendant. Angew Chem Int Ed Engl 2023; 62:e202217365. [PMID: 36522304 DOI: 10.1002/anie.202217365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/08/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022]
Abstract
The development of polymers with on-demand degradability is required to alleviate the current global issues on polymer-waste pollution. Therefore, we designed a vinyl ether monomer with an o-nitrobenzyl (oNBn) group as a photo-deprotectable pendant (oNBnVE) and synthesized an alternating copolymer with an oNBn-capped acetal backbone via cationic copolymerization with p-tolualdehyde (pMeBzA). The resultant alternating copolymer could be rapidly degraded into lower-molecular-weight compounds upon simple exposure to UV irradiation without any reactants or catalysts, while it was sufficiently stable toward heat and ambient light. This degradation proceeds via cleavage of the hemiacetal structure generated upon photo-deprotection of the oNBn pendant. The oNBn-peculiar degradability allowed the exclusive photo-degradation of the oNBnVE/pMeBzA segments in a diblock copolymer composed of oNBnVE/pMeBzA and benzyl vinyl ether (BnVE)/pMeBzA segments.
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Affiliation(s)
- Hiroyuki Kubota
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Makoto Ouchi
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University Nishikyo-ku, Kyoto, 615-8510, Japan
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6
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Do PT, Poad BLJ, Frisch H. Programming Photodegradability into Vinylic Polymers via Radical Ring-Opening Polymerization. Angew Chem Int Ed Engl 2023; 62:e202213511. [PMID: 36535898 PMCID: PMC10108003 DOI: 10.1002/anie.202213511] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 11/15/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022]
Abstract
Incorporation of photolabile moieties into the polymer backbone holds promise to remotely-control polymer degradation. However, suitable synthetic avenues are limited, especially for radical polymerizations. Here we report a strategy to program photodegradability into vinylic polymers by exploiting the wavelength selectivity of photocycloadditions for radical ring-opening polymerization (rROP). Irradiation of coumarin terminated allylic sulfides with UVA light initiated intramolecular [2+2] photocycloaddition producing cyclic macromonomers. Subsequent RAFT-mediated rROP with methyl acrylate yielded copolymers that inherited the photoreactivity of the cyclic parent monomer. Irradiation with UVB initiated efficient photocycloreversion of the coumarin dimers, causing polymer degradation within minutes under UVB light or days under sunlight exposure. Our synthetic strategy may pave the way to insert photolabile linkages into vinylic polymers, tuning degradation for specific wavelengths.
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Affiliation(s)
- Phuong T Do
- School of Chemistry and Physics, Queensland University of Technology, 2 George Street, Brisbane, QLD-4000, Australia.,Centre for Materials Science, Queensland University of Technology, 2 George Street, Brisbane, QLD-4000, Australia
| | - Berwyck L J Poad
- School of Chemistry and Physics, Queensland University of Technology, 2 George Street, Brisbane, QLD-4000, Australia.,Centre for Materials Science, Queensland University of Technology, 2 George Street, Brisbane, QLD-4000, Australia.,Central Analytical Research Facility, Queensland University of Technology, 2 George Street, Brisbane, QLD-4000, Australia
| | - Hendrik Frisch
- School of Chemistry and Physics, Queensland University of Technology, 2 George Street, Brisbane, QLD-4000, Australia.,Centre for Materials Science, Queensland University of Technology, 2 George Street, Brisbane, QLD-4000, Australia
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7
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Mutlu H, Barner L. Getting the Terms Right: Green, Sustainable, or Circular Chemistry? MACROMOL CHEM PHYS 2022. [DOI: 10.1002/macp.202200111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Hatice Mutlu
- Soft Matter Synthesis Laboratory (SML) Karlsruhe Institute of Technology (KIT) Hermann‐von‐Helmholtz‐Platz 1 Eggenstein‐Leopoldshafen 76344 Germany
| | - Leonie Barner
- Centre for a Waste‐Free World, School of Chemistry and Physics Faculty of Science, Queensland University of Technology Brisbane QLD 4000 Australia
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8
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Gavriel A, Sambrook M, Russell AT, Hayes W. Recent advances in self-immolative linkers and their applications in polymeric reporting systems. Polym Chem 2022. [DOI: 10.1039/d2py00414c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Interest in self-immolative chemistry has grown over the past decade with more research groups harnessing the versatility to control the release of a compound from a larger chemical entity, given...
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9
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Irshadeen IM, Walden SL, Wegener M, Truong VX, Frisch H, Blinco JP, Barner-Kowollik C. Action Plots in Action: In-Depth Insights into Photochemical Reactivity. J Am Chem Soc 2021; 143:21113-21126. [PMID: 34859671 DOI: 10.1021/jacs.1c09419] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Predicting wavelength-dependent photochemical reactivity is challenging. Herein, we revive the well-established tool of measuring action spectra and adapt the technique to map wavelength-resolved covalent bond formation and cleavage in what we term "photochemical action plots". Underpinned by tunable lasers, which allow excitation of molecules with near-perfect wavelength precision, the photoinduced reactivity of several reaction classes have been mapped in detail. These include photoinduced cycloadditions and bond formation based on photochemically generated o-quinodimethanes and 1,3-dipoles such as nitrile imines as well as radical photoinitiator cleavage. Organized by reaction class, these data demonstrate that UV/vis spectra fail to act as a predictor for photochemical reactivity at a given wavelength in most of the examined reactions, with the photochemical reactivity being strongly red shifted in comparison to the absorption spectrum. We provide an encompassing perspective of the power of photochemical action plots for bond-forming reactions and their emerging applications in the design of wavelength-selective photoresists and photoresponsive soft-matter materials.
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Affiliation(s)
- Ishrath Mohamed Irshadeen
- School of Chemistry and Physics, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia.,Centre for Materials Science, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
| | - Sarah L Walden
- School of Chemistry and Physics, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia.,Centre for Materials Science, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
| | - Martin Wegener
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Vinh X Truong
- School of Chemistry and Physics, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia.,Centre for Materials Science, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
| | - Hendrik Frisch
- School of Chemistry and Physics, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia.,Centre for Materials Science, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
| | - James P Blinco
- School of Chemistry and Physics, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia.,Centre for Materials Science, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia
| | - Christopher Barner-Kowollik
- School of Chemistry and Physics, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia.,Centre for Materials Science, Queensland University of Technology (QUT), 2 George Street, Brisbane, Queensland 4000, Australia.,Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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10
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UV-Protected Polyurethane/ f-Oil Fly Ash-CeO 2 Coating: Effect of Pre-Mixing f-Oil Fly Ash-CeO 2 with Monomers. Polymers (Basel) 2021; 13:polym13193232. [PMID: 34641048 PMCID: PMC8512524 DOI: 10.3390/polym13193232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/13/2021] [Accepted: 09/17/2021] [Indexed: 11/16/2022] Open
Abstract
A series of UV-protected coatings were prepared using cerium-oxide-functionalized oil fly ash (f-OFA-CeO2) in waterborne polyurethane (WBPU) dispersions. Three monomers, namely, poly(tetramethyleneoxide glycol) (PTMG), polydimethylsiloxane-hydroxy terminated (PDMS) and 4,4-dicyclohexylmethane diisocyanate (H12MDI), were used to pre-mix with f-OFA-CeO2 separately, followed by the synthesis of WBPU/f-OFA-CeO2 dispersions. The f-OFA-CeO2 distribution and enrichment into any part (top/bottom/bulk) of the coating was strongly affected by the pre-mixing of f-OFA-CeO2. The f-OFA-CeO2 was densely distributed in the top, bottom and bulk when the f-OFA-CeO2 was pre-mixed with PDMS, H12MDI and PTMG, respectively. Only an f-OFA-CeO2-enriched top surface showed excellent UV protection. The lowest UV-degraded exposed coating was found when the top surface of the coating was f-OFA-CeO2-enriched.
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Psarrou M, Kothri MG, Vamvakaki M. Photo- and Acid-Degradable Polyacylhydrazone-Doxorubicin Conjugates. Polymers (Basel) 2021; 13:polym13152461. [PMID: 34372064 PMCID: PMC8348397 DOI: 10.3390/polym13152461] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 07/21/2021] [Accepted: 07/22/2021] [Indexed: 11/16/2022] Open
Abstract
Light-mediated polymer degradation has attracted considerable attention in various applications, including photo-patterning, tissue engineering and photo-triggered drug delivery. In this study, we report the synthesis and characterization of a new, linear, main-chain photo- and acid-degradable copolymer based on acylhydrazone linkages. The polymer was synthesized via a step-growth copolymerization of adipic acid dihydrazide with a bifunctional poly(ethylene glycol) bearing benzaldehyde end-groups, under mild acidic conditions, to afford a hydrophilic PEG-alt-adipic acid (PEG-alt-AA) alternating copolymer. The synthesized polymer was characterized by size exclusion chromatography, proton nuclear magnetic resonance and attenuated total reflection-Fourier transform infrared spectroscopies. The main-chain photo- and acid-induced degradation of the copolymer in dimethylsulfoxide and water, respectively, was verified by UV-vis spectroscopy at light intensities as low as 0.1 mW cm−2 at λ = 254 nm. Next, a model anticancer drug, doxorubicin (DOX), was chemically linked to the polymer chain end(s) via acylhydrazone bond(s), resulting in amphiphilic PEG-alt-adipic acid-DOX (PEG-alt-AA-DOX) polymer–drug conjugates. The conjugates were self-assembled in water to form spherical nanoparticles, as evidenced by scanning and transmission electron microscopies. The irradiation of the self-assembled PEG-alt-AA-DOX conjugates with UV light and the decrease of the solution pH resulted in the disruption of the assemblies due to the photolysis and acidolysis of the acylhydrazone bonds, and the release of the therapeutic cargo.
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Affiliation(s)
- Maria Psarrou
- Department of Materials Science and Technology, University of Crete, Vasilika Vouton, 700 13 Heraklion, Crete, Greece;
| | - Martha Georgia Kothri
- School of Medicine, University of Crete, Vasilika Vouton, 700 13 Heraklion, Crete, Greece;
| | - Maria Vamvakaki
- Department of Materials Science and Technology, University of Crete, Vasilika Vouton, 700 13 Heraklion, Crete, Greece;
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Vasilika Vouton, 700 13 Heraklion, Crete, Greece
- Correspondence: ; Tel.: +30-2810-545019
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