We examine the use of thionylphosphazene-based block copolymers as matrixes for oxygen sensor applications. Poly(aminothionylphosphazene)-b-poly(tetrahydrofuran) (PATPy-PTHFx) block copolymers were prepared via reaction of ring-opened poly(chlorothionylphosphazene) with THF and subsequently with excess n-butylamine (to form PBATPy-PTHFx) or methylamine (to form PMATPy-PTHFx). The block copolymers were characterized by NMR, gel permeation chromatography, and differential scanning calorimetry. Films of PBATPy-PTHFx block copolymers containing platinum octaethylporphyrin or [Ru(dpp)3]Cl2 (dpp = 4,7-diphenyl-1,10-phenanthroline) as the oxygen-sensitive chromophore were prepared, and time-scan experiments were carried out to determine the diffusion coefficients, Do2, and solubilities, So2, of oxygen therein. Despite microphase separation, the data fit well to a simple Fick's law description of oxygen diffusion and gave Do2 values smaller than that for the n-butylamino-substituted PBATP635. For films freshly annealed above the melting point of PTHFx, the Do2 values were 35-50% (dye-dependent) larger than after aging 3 days at room temperature. Films with [Ru(dpp)3]Cl2 as the dye were evaluated as media for phosphorescent pressure-sensing. The dye-containing polymer films exhibit linear Stern-Volmer-like plots, even at high dye concentrations, as well as good photostability, and significantly higher sensitivity to oxygen quenching than simple mixtures of the analogous homopolymers.
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http://dx.doi.org/10.1021/ac9909610 | DOI Listing |
Drug Deliv Transl Res
January 2025
Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, T6G 2E1, Canada.
In this study, a novel inhibitor of ERCC1/XPF heterodimerization, A4, was used as an inhibitor of repair for DNA damage by platinum-based chemotherapeutics. Nano-formulations of A4 were developed, using self-assembly of the following block copolymers: methoxy-poly(ethylene oxide)-block-poly(α-benzyl carboxylate-ε-caprolactone) (PEO-b-PBCL), methoxy-poly(ethylene oxide)-block-poly(ε-caprolactone) (PEO-b-PCL), or methoxy-poly(ethylene oxide)-block-poly (D, L, lactide) (PEO-b-PDLA 50-50). The nano-formulations were characterized for their average diameter, polydispersity, morphology, A4 encapsulation and in vitro release.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Chang Chun Institute of Applied Chemistry Chinese Academy of Sciences, Key Laboratory of Polymer Ecomaterials, 5625 Renmin Street, Changchun, , 130022, Changchun, CHINA.
Living cationic polymerization (LCP) is a classical technique for precision polymer synthesis; however, due to the high sensitivity of cationic active species towards chain-transfer/termination events, it is notoriously difficult to control polymerization under mild conditions, which inhibits its progress in advanced materials engineering. Here, we unlock a practical anion-binding catalytic strategy to address the historical dilemma in LCP. Our experimental and mechanistic studies demonstrate that commercially accessible hexafluoroisopropanol (HFIP), when used in high loading, can create higher-order HFIP aggregates to tame dormant-active species equilibrium via non-covalent anion-binding principle, in turn inducing distinctive polymerization kinetics behaviors that grant efficient chain propagation while minimizing competitive side reactions.
View Article and Find Full Text PDFBiomater Sci
January 2025
Zhejiang Key Laboratory of Smart BioMaterials, and College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, China.
Accurate imaging of tumor hypoxia is critical for early cancer diagnosis and clinical outcomes, highlighting the great need for its detection specificity and sensitivity. In this report, we propose a probe (HTRNP) that simultaneously has hypoxia-targeting and hypoxia-responsive capabilities to enhance the tumor hypoxia imaging efficiency. HTRNP was successfully prepared through the encapsulation of Pt(II)-tetrakis(pentafluorophenyl)porphyrin (PtPFPP), which exhibits hypoxia-dependent phosphorescence, within the amphiphilic block copolymer OPDMA-PF, which has hypoxia-targeting tertiary amine -oxide moieties and hydrophobic perfluorobenzene ring structures, which highly improved the loading content and water solubility of PtPFPP.
View Article and Find Full Text PDFMacromol Rapid Commun
January 2025
Chimie ParisTech, CNRS, Institut de Recherche de Chimie Paris, PSL University, Paris, 75005, France.
The development of catalysts that are both robust and highly active at room temperature can often be seen as a major challenge in anionic polymerization. However, these properties are desirable for polymer synthesis because they allow for easy and sustainable production of interesting materials. Here, iron and magnesium complexes are used to form in situ generated metalate complexes that are shown to be highly active in the room temperature copolymerization of methyl methacrylate and lactide.
View Article and Find Full Text PDFChemistry
January 2025
Beijing Institute of Technology, Polymer Materials, 5 Zhongguancun Nandajie, 100081, Beijing, CHINA.
The self-assembly of block copolymers (BCPs) to form nanostructures of various morphologies and controllable dimensions has been a very promising research area in nanotechnology in recent decades. This review mainly summarizes the recent advances in precise and controllable self-assembly of BCPs through a tailored nucleation-growth strategy to modulate the self-assembly behavior of the BCPs. These efforts have led to a better understanding of the self-assembly mechanisms and opened new possibilities for creating novel materials with designable properties.
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