Novel AIEgen-Functionalized Diselenide-Crosslinked Polymer Gels as Fluorescent Probes and Drug Release Carriers

Stimuli-responsive functional gels have shown significant potential for application in biosensing and drug release systems. In this study, aggregation-induced emission luminogen (AIEgen)-functionalized, diselenide-crosslinked polymer gels were synthesized via free radical copolymerization. A series of polymer gels with different crosslink densities or tetraphenylethylene (TPE) contents were synthesized. The diselenide crosslinker in the gels could be fragmented in the presence of H2O2 or dithiothreitol (DTT) due to its redox-responsive property. Thus, the TPE-containing polymer chains were released into the aqueous solution. As a result, the aqueous solution exhibited enhanced fluorescence emission due to the strong hydrophobicity of TPE. The degradation of polymer gels and fluorescence enhancement in an aqueous solution under different H2O2 or DTT concentrations were studied. Furthermore, the polymer gels could be used as drug carriers, suggesting a visual drug release process under the action of external redox agents. The AIEgen-functionalized, diselenide-crosslinked polymer gels hold great potential in the biomedical area for biosensing and controlled drug delivery.

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Weibull Modeling of Controlled Drug Release from Ag-PMA Nanosystems

Polymers ◽

10.3390/polym13172897 ◽

2021 ◽

Vol 13 (17) ◽

pp. 2897

Author(s):

Carmelo Corsaro ◽

Giulia Neri ◽

Angela Maria Mezzasalma ◽

Enza Fazio

Keyword(s):

Drug Release ◽

Controlled Drug Release ◽

Drug Carriers ◽

Polymer Chains ◽

Patient Treatment ◽

Release Mechanism ◽

Release Process ◽

Precise Control ◽

Biochemical Processes ◽

Drug Selectivity

Traditional pharmacotherapy suffers from multiple drawbacks that hamper patient treatment such as antibiotic resistances or low drug selectivity and toxicity during systemic applications. Some functional hybrid nanomaterials are designed to handle the drug release process under remote-control. More attention has recently been paid to synthetic polyelectrolytes for their intrinsic properties which allow them to rearrange into compact structures, ideal to be used as drug carriers or probes influencing biochemical processes. The presence of Ag nanoparticles (NPs) in the Poly methyl acrylate (PMA) matrix leads to an enhancement of drug release efficiency, even using a low-power laser whose wavelength is far from the Ag Surface Plasmon Resonance (SPR) peak. Further, compared to the colloids, the nanofiber-based drug delivery system has shown shorter response time and more precise control over the release rate. The efficiency and timing of involved drug release mechanisms has been estimated by the Weibull distribution function, whose parameters indicate that the release mechanism of nanofibers obeys Fick’s first law while a non-Fickian character controlled by diffusion and relaxation of polymer chains occurs in the colloidal phase.

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Synthesis of Poly(acrylamide-Methacrylate)-G-Octylphenyl Polyoxyethylene and its Micellar Behavior in Aqueous Solution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.3337 ◽

2011 ◽

Vol 239-242 ◽

pp. 3337-3341

Author(s):

Dong Xia Zhang ◽

Wen Hui Hu ◽

Fang Ping Wang ◽

Lin Ke Xue ◽

Xin Zhen Du

Keyword(s):

Aqueous Solution ◽

Graft Copolymer ◽

Main Chain ◽

Radical Copolymerization ◽

Molar Ratio ◽

Free Radical Copolymerization ◽

Transmission Electron ◽

Spherical Micelles ◽

Acrylamide Monomer ◽

Poly Acrylamide

An amphiphilic graft copolymer with poly(acrylamide-methacrylate) as a main chain and octylphenyl polyoxyethylene as side chains (P(AM-MA)-g-C8PhEO10) was successfully synthesized via free radical copolymerization. The structure and the composition of the graft copolymer were characterized by FTIR, 1H-NMR and elemental analysis (EA) in detail. The absolute molecular weight of the copolymer is 1.304×106, as determined by static light scattering (SLS). The molar ratio of acrylamide monomer to the macromonomer is 33:1 in the copolymer and 53 C8PhEO10 branch chains attach to a P(AM-MA) backbone. The micellar behavior of P(AM-MA)-g-C8PhEO10 was preliminarily studied by means of surface tension measurements, transmission electron microscope (TEM) in aqueous solution. It was found that the stable spherical micelles with core-shell structure are formed and polymolecular micelles are larger and more compact than monomolecular micelles. In addition, the graft copolymer has favorable thermal stability.

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Synthesis, characterization, and properties of new polystyrene-SiO2 hybrid sol-gel materials

Journal of Materials Research ◽

10.1557/jmr.1993.1143 ◽

1993 ◽

Vol 8 (5) ◽

pp. 1143-1152 ◽

Cited By ~ 74

Author(s):

Yen Wei ◽

Dachuan Yang ◽

Liguang Tang ◽

MaryGail K. Hutchins

Keyword(s):

Hybrid Materials ◽

Room Temperature ◽

Sol Gel ◽

Glass Network ◽

Radical Copolymerization ◽

Polymer Chains ◽

Free Radical Copolymerization ◽

New Family ◽

Polymer Precursors ◽

Covalently Bonded

A new family of organic-inorganic hybrid materials has been prepared by incorporating polystyrene structure units covalently into the SiO2 glass network via the sol-gel approach. The polymer precursors were synthesized by free-radical copolymerization of styrene with 3-(trimethoxysilyl)propyl methacrylate (MSMA) at various feeds. These copolymers were then hydrolyzed and co-condensed with tetraethyl orthosilicate in tetrahydrofuran at room temperature to afford monolithic polystyrene-SiO2 hybrid sol-gel materials having SiO2 contents of 15 to 84% by weight. The hybrid materials derived from the copolymers with MSMA contents greater than 22 mol% have excellent optical transparency. In these transparent hybrid materials, the polymer chains should be uniformly distributed in and covalently bonded to the amorphous SiO2 matrices. The bulk properties of these materials including density, refractive index, and hardness were found to be related to their molecular compositions and can be tailored by varying the polymer contents.

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Influence of Cyclodextrins on Thermosensitive and Fluorescent Properties of Pyrenyl-Containing PDMAA

Polymers ◽

10.3390/polym11101569 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1569 ◽

Cited By ~ 1

Author(s):

Dong ◽

Sun ◽

Chen ◽

Yang ◽

Li ◽

...

Keyword(s):

Aqueous Solution ◽

Emission Intensity ◽

Solution Concentration ◽

Radical Copolymerization ◽

Ethanol Solution ◽

Solution Temperature ◽

Fluorescent Properties ◽

High Concentration ◽

Excimer Emission ◽

Free Radical Copolymerization

A series of pyrenyl-containing PDMAA copolymers were prepared by free radical copolymerization of dimethylacrylamide (DMAA) with pyrenebutanoyloxy ethyl methacrylate (PyBEMA). The structure of as-prepared copolymers was characterized by UV, FT-IR and 1H NMR spectroscopy. The effect of cyclodextrins (α-CD, β-CD and γ-CD) on the thermosensitivity and fluorescence of the copolymers in aqueous solutions were investigated. It was found that the as-prepared copolymers exhibit lower critical solution temperature (LCST)-type thermosensitivity. Cloud point (Tcp) decreases with the increasing molar content of PyBEMA unit in the copolymers. Tcp of the copolymers increases after the CD is added from half molar to equivalent amount relative to pyrenyl moiety, and that further adding twice equivalent CD results in a slight decrease in Tcp. The copolymers exhibit a pyrene emission located at 377 nm and a broad excimer emission centered at 470 nm. The copolymers in water present a stronger excimer emission (Intensity IE) relative to monomer emission (Intensity IM) than that in ethanol. The IE/IM values decrease after the addition of equivalent α-CD, β-CD and γ-CD into the copolymers in aqueous solution, respectively. The IE/IM values abruptly increase as the copolymers’ concentration is over 0.2 mg/L whether in ethanol solution or aqueous solution with or without CD, from which can probably be inferred that intra-polymeric pyrene aggregates dominate for solution concentration below 0.2 mg/L and inter-polymeric pyrene aggregates dominate over 0.2 mg/L. Furthermore, the formation of the CD pseudopolyrotaxanes makes it possible to form pyrene aggregates. For high concentration of 5 g/L, the copolymers and their inclusion complexes completely exhibit an excimer emission. The IE values abruptly increased as the temperature went up to Tcp, which indicates that the IE values can be used to research phase separation of polymers.

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Multiple stimuli-responsive selenium-functionalized biodegradable starch-based hydrogels

Soft Matter ◽

10.1039/c7sm02137b ◽

2018 ◽

Vol 14 (6) ◽

pp. 921-926 ◽

Cited By ~ 21

Author(s):

Tongbing Sun ◽

Caizhen Zhu ◽

Jian Xu

Keyword(s):

Free Radical ◽

Drug Release ◽

Biomedical Applications ◽

Radical Copolymerization ◽

Enzyme Hydrolysis ◽

Stimuli Responsive ◽

Free Radical Copolymerization ◽

Redox Responsive

Biodegradable diselenide cross-linked starch-based hydrogels, composed of starch chain backbones with an enzyme hydrolysis property and selenium-containing cross-linkers with a redox responsive cleavage property, were synthesizedviafree radical copolymerization and used as stimuli-responsive drug release materials for biomedical applications.

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Adsorption and Desorption of Na+ and NO3− Ions on Thermosensitive NIPAM-co-DMAAPS Gel in Aqueous Solution

Indonesian Journal of Chemistry ◽

10.22146/ijc.25297 ◽

2017 ◽

Vol 17 (3) ◽

pp. 446 ◽

Cited By ~ 5

Author(s):

Eva Oktavia Ningrum ◽

Agus Purwanto ◽

Eka Octaviyatna Mulyadi ◽

Dinny Islamiah Dewitasari ◽

Sumarno Sumarno

Keyword(s):

Aqueous Solution ◽

Free Radical ◽

Solution Concentration ◽

Radical Copolymerization ◽

Effect Of Temperature ◽

Free Radical Copolymerization ◽

Adsorption And Desorption ◽

Temperature Swing ◽

Adsorption Amount ◽

The Relationship

Adsorbent gel with the ability to absorb and to desorb Na+ and NO3− ions simultaneously with temperature swing was synthesized by free radical copolymerization reaction of N-isopropylacrylamide (NIPAM) and N,N-dimethyl-(acrylamidopropyl)ammonium propane sulfonate (DMAAPS). In this study, NIPAM acts as a thermosensitive agent and DMAAPS as an adsorbent agent. The purpose of this research is to investigate the effect of temperature and solution concentration on the swelling, adsorption, and desorption behaviors of NIPAM-co-DMAAPS gel. The relationship between adsorption and desorption behaviors of the gel was also elucidated. NaNO3 solution was selected as the target solution in swelling, adsorption, and desorption test. It was observed that the swelling degree of the gel increased as temperature and solution concentration raised. The adsorption amount of ions decreased with the increase of temperature. In contrast, the amount of ions desorbed from the gel increased linearly with temperature.

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Freeze-etch TEM of aqueous polymer gel network morphology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145327 ◽

1986 ◽

Vol 44 ◽

pp. 796-797

Author(s):

J. A. N. Zasadzinski ◽

R. K. Prud'homme

Keyword(s):

Metal Ion ◽

Polymer Network ◽

Polymer Gels ◽

Polymer Gel ◽

Deformation History ◽

Crosslinked Polymer ◽

Aqueous Polymer ◽

History Of ◽

Gel Network ◽

Network Morphology

The rheological and mechanical properties of crosslinked polymer gels arise from the structure of the gel network. In turn, the structure of the gel network results from: thermodynamically determined interactions between the polymer chain segments, the interactions of the crosslinking metal ion with the polymer, and the deformation history of the network. Interpretations of mechanical and rheological measurements on polymer gels invariably begin with a conceptual model of,the microstructure of the gel network derived from polymer kinetic theory. In the present work, we use freeze-etch replication TEM to image the polymer network morphology of titanium crosslinked hydroxypropyl guars in an attempt to directly relate macroscopic phenomena with network structure.

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Dual Release Model to Evaluate Dissolution Profiles from Swellable Drug Polyelectrolyte Matrices

Current Drug Delivery ◽

10.2174/1567201817666200512093115 ◽

2020 ◽

Vol 17 (6) ◽

pp. 511-522 ◽

Cited By ~ 2

Author(s):

Alicia Graciela Cid ◽

María Verónica Ramírez-Rigo ◽

María Celeste Palena ◽

Elio Emilio Gonzo ◽

Alvaro Federico Jimenez-Kairuz ◽

...

Keyword(s):

Experimental Data ◽

Drug Release ◽

Inflection Point ◽

Release Profile ◽

Experimental Point ◽

Extended Model ◽

Release Process ◽

Proposed Model ◽

Dual Release ◽

Release Model

Background: Mathematical modeling in modified drug release is an important tool that allows predicting the release rate of drugs in their surrounding environment and elucidates the transport mechanisms involved in the process. Objective: The aim of this work was to develop a mathematical model that allows evaluating the release profile of drugs from polymeric carriers in which the swelling phenomenon is present. Methods: Swellable matrices based on ionic complexes of alginic acid or carboxymethylcellulose with ciprofloxacin were prepared and the effect of adding the polymer sodium salt on the swelling process and the drug release was evaluated. Experimental data from the ciprofloxacin release profiles were mathematically adjusted, considering the mechanisms involved in each stage of the release process. Results: A proposed model, named “Dual Release” model, was able to properly fit the experimental data of matrices presenting the swelling phenomenon, characterized by an inflection point in their release profile. This entails applying the extended model of Korsmeyer-Peppas to estimate the percentage of drug released from the first experimental point up to the inflection point and then a model called Lumped until the final time, allowing to adequately represent the complete range of the drug release profile. Different parameters of pharmaceutical relevance were calculated using the proposed model to compare the profiles of the studied matrices. Conclusion: The “Dual Release” model proposed in this article can be used to predict the behavior of complex systems in which different mechanisms are involved in the release process.

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Novel Self-Healing Metallocopolymers with Pendent 4-Phenyl-2,2′:6′,2″-terpyridine Ligand: Kinetic Studies and Mechanical Properties

Polymers ◽

10.3390/polym13111760 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1760

Author(s):

Rose K. Baimuratova ◽

Gulzhian I. Dzhardimalieva ◽

Evgeniy V. Vaganov ◽

Valentina A. Lesnichaya ◽

Gulsara D. Kugabaeva ◽

...

Keyword(s):

Critical Role ◽

Specific Effect ◽

Kinetic Studies ◽

Radical Copolymerization ◽

Self Healing ◽

Free Radical Copolymerization ◽

Polymer Hydrogels ◽

Close Proximity ◽

Metal Group ◽

Metal Polymer

We report here our successful attempt to obtain self-healing supramolecular hydrogels with new metal-containing monomers (MCMs) with pendent 4-phenyl-2,2′:6′,2″-terpyridine metal complexes as reversible moieties by free radical copolymerization of MCMs with vinyl monomers, such as acrylic acid and acrylamide. The resulting metal-polymer hydrogels demonstrate a developed system of hydrogen, coordination and electron-complementary π–π stacking interactions, which play a critical role in achieving self-healing. Kinetic data show that the addition of a third metal-containing comonomer to the system decreases the initial polymerization rate, which is due to the specific effect of the metal group located in close proximity of the active center on the growth of radicals.

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