European Polymer Journal最新文献_第4页

Kinetics and scale inhibition application studies towards bulk and RAFT copolymerization of maleic anhydride and acrylic acid 马来酸酐和丙烯酸的散装和 RAFT 共聚动力学和阻垢应用研究

IF 5.8 2区化学 Q1 POLYMER SCIENCE

European Polymer Journal

Pub Date : 2024-10-12 DOI: 10.1016/j.eurpolymj.2024.113504

Poly(maleic anhydride) (PMA) is commonly reckoned as a better water scale inhibitor than poly(acrylic acid) (PAA) since each maleic anhydride unit can supply two carboxylic acid groups. However, pure PMA is difficult to achieve because the steric effect of its monomer MA. Herein, we synthesize copoly(MA-AA) copolymer by bulk polymerization method (bulk-copoly(MA-AA)), which avoids the use of any solvents which have to be removed afterwards. In addition, we also synthesize copoly(MA-AA) by reversible addition-fragmentation chain transfer (RAFT) polymerization method to afford RAFT-copoly(MA-AA) with low polydispersity index (PDI) less than 1.2, and the performance of RAFT-copoly(MA-AA) in water scale inhibition is more excellent relative to bulk-copoly(MA-AA). We also synthesize other copoly(MA-AA) copolymers by varying the molar ratio of MA to AA to study the polymerization mechanism. Through the static scale inhibition experiment, it is concluded that when the concentration of copoly(MA-AA) is 80 mg/L, the scale inhibition performance of RAFT-copoly(MA-AA) can reach 96.50 % which is the best among the control samples. It is also found that only 1:1 alternating copolymerization of MA and AA could be achieved as demonstrated by ¹H nuclear magnetic resonance spectra of the copolymers, evidencing the strong steric hindrance of MA for its homo-polymerization.

聚（马来酸酐）（PMA）通常被认为是比聚（丙烯酸）（PAA）更好的水垢抑制剂，因为每个马来酸酐单元可以提供两个羧酸基团。然而，由于单体 MA 的立体效应，纯 PMA 很难实现。在此，我们采用体聚合法（bulk-copoly(MA-AA)）合成了共聚（MA-AA）共聚物，这种方法避免了使用任何溶剂，因为溶剂必须在聚合后清除。此外，我们还采用可逆加成-断裂链转移（RAFT）聚合法合成了共聚物（MA-AA），得到了聚分散指数（PDI）小于 1.2 的 RAFT-共聚物（MA-AA），RAFT-共聚物（MA-AA）的阻水垢性能相对于 bulk-共聚物（MA-AA）更为优异。我们还通过改变 MA 与 AA 的摩尔比合成了其他共聚（MA-AA）共聚物，以研究其聚合机理。通过静态阻垢实验得出结论：当共聚(MA-AA)的浓度为 80 mg/L 时，RAFT-共聚(MA-AA)的阻垢性能可达 96.50%，是对照样品中最好的。通过共聚物的 1H 核磁共振谱还发现，MA 和 AA 只能实现 1:1 的交替共聚，这证明 MA 对其均聚具有很强的立体阻碍作用。

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引用次数: 0

High fire-safety epoxy resin with functional polymer/metal–organic framework hybrids 含功能聚合物/金属有机框架杂化物的高防火安全性环氧树脂

IF 5.8 2区化学 Q1 POLYMER SCIENCE

European Polymer Journal

Pub Date : 2024-10-12 DOI: 10.1016/j.eurpolymj.2024.113505

Petroleum-derived bisphenol A-type epoxy resins are highly flammable and vulnerable to fires, limiting their wide applications. The addition of inorganic flame retardants to the epoxy resin improves the flame retardancy of the epoxy resin, but it is difficult to distribute them evenly in the polymer matrix. Here, we introduce flame-retardant epoxy resins supported by the functional polymer/metal–organic framework hybrids. The hybrids, consisted of polyaniline, poly (4-styrenesulfonic acid), and Zr-based organic frameworks, demonstrate effective flame-retardant effects with homogeneous distribution in the epoxy based on their synergistic effects of each material. Compared with pure epoxy resin, the presence of 1 wt% of hybrid flam-retardant remarkably decreases the combustion, the heat release, and the smoke production.

从石油中提取的双酚 A 型环氧树脂极易燃烧，容易引发火灾，因此限制了其广泛应用。在环氧树脂中添加无机阻燃剂可提高环氧树脂的阻燃性，但很难将其均匀分布在聚合物基体中。在此，我们介绍了由功能聚合物/金属有机框架杂化物支撑的阻燃环氧树脂。这些杂化物由聚苯胺、聚（4-苯乙烯磺酸）和锆基有机框架组成，基于每种材料的协同作用，它们在环氧树脂中均匀分布，表现出有效的阻燃效果。与纯环氧树脂相比，1 wt%的混合阻燃剂可显著减少燃烧、热释放和烟雾产生。

引用次数: 0

Chain relaxation of carborane segments with tailored chain length at high temperatures 高温下具有定制链长的碳化硼段的链松弛

IF 5.8 2区化学 Q1 POLYMER SCIENCE

European Polymer Journal

Pub Date : 2024-10-12 DOI: 10.1016/j.eurpolymj.2024.113509

High-performance thermoset polymers have good thermal stability due to their highly crosslinked network, while also represent topological constraints that restrict cooperative segmental motion, making it difficult to relax stresses even at high temperatures. Failure of most thermoset polymers at high temperatures is due to ineffective stress relaxation, which limits the use of thermoset polymers in harsh environments. Herein, we employed a cyclosiloxane hybrid polymer (CHP) containing o-carborane segments with tailored carbon chain length to relieve internal stress. The introduction of o-carborane and lengthening of carbon chain both increased the CHP fractional free volume, and reduced the activation energy required in the later stages of the curing process. The carbon chain changed the conformation to achieve chain relaxation by stretching and rotating the carbon–carbon bonds at high temperatures, which avoided cracking and increased the failure temperature of the CHP. Furthermore, the adhesion strength of the o-carborane modified CHP reached a maximum of 2.15 MPa, surpassing 1.23 MPa of the neat CHP. The o-carborane modified CHP with the longest carbon chain exhibited good stability while supporting 1 kg load for 5 min when subjected to ablation, whereas the neat CHP failed after only 47 s. The o-carborane-modified CHP exhibited enhanced high-temperature properties through chain relaxation to inhibit cracking and in situ generation of boron oxide at high temperatures to protect the resin matrix.

高性能热固性聚合物因其高度交联的网络而具有良好的热稳定性，但同时也存在拓扑约束，限制了分段的协同运动，因此即使在高温下也很难松弛应力。大多数热固性聚合物在高温下失效的原因是应力松弛效果不佳，这限制了热固性聚合物在恶劣环境中的应用。在此，我们采用了一种环硅氧烷杂化聚合物（CHP），其中含有碳链长度可调的邻碳硼烷段，以缓解内应力。邻碳硼烷的引入和碳链的延长都增加了 CHP 的自由体积分数，并降低了固化过程后期所需的活化能。碳链改变了构象，在高温下通过碳碳键的拉伸和旋转实现了链松弛，从而避免了开裂，提高了 CHP 的失效温度。此外，邻碳硼烷改性 CHP 的粘合强度最大达到 2.15 兆帕，超过了纯 CHP 的 1.23 兆帕。碳链最长的邻碳硼烷改性热电联产在承受烧蚀 5 分钟 1 千克载荷时表现出良好的稳定性，而纯热电联产仅在 47 秒后就失效了。邻碳硼烷改性热电联产通过链松弛抑制开裂，并在高温下原位生成氧化硼保护树脂基体，从而增强了高温性能。

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引用次数: 0

Computer-aided design of thermosetting benzoxazoles containing bis-endoalkynyl groups: Low melting points and high thermal stability 含有双内炔基（bis-endoalkynyl）的热固性苯并恶唑的计算机辅助设计：低熔点和高热稳定性

IF 5.8 2区化学 Q1 POLYMER SCIENCE

European Polymer Journal

Pub Date : 2024-10-12 DOI: 10.1016/j.eurpolymj.2024.113503

High-temperature-resistant polybenzoxazoles (PBOs) have recently become a prominent research area due to their potential applications in aviation and aerospace. However, achieving a balance between thermal stability and processability remains a significant challenge. In this study, a computer-aided method to develop PBOs with high thermal stability and processability is explored. First, thermoset benzoxazoles (CPBOs) are designed using a material genomic approach. Subsequently, their zero shear viscosity, temperature at 50 % thermal weight loss, dielectric constant and dielectric loss are predicted using a computer-aided method. Finally, two screened thermosetting benzoxazoles, CPBO-1 and CPBO-6, are synthesized and experimentally validated. The experiments indicate that their melting points are below 100 °C, with the lowest melt viscosities being 0.5 Pa•s and 1.5 Pa•s, respectively. The corresponding polymers, pCPBO-1 and pCPBO-6, feature high thermal stability. The 5 % weight loss temperature of pCPBO-1 in N₂ is 618.9 °C, while the dielectric constant and dielectric loss are 3.1 and 0.0063, respectively. These are excellent values for thermosetting resins. This computer-aided screening method is more efficient and cost-effective compared to conventional trial-and-error methods.

耐高温聚苯并恶唑（PBO）因其在航空和航天领域的潜在应用，最近已成为一个突出的研究领域。然而，如何在热稳定性和加工性能之间取得平衡仍是一项重大挑战。本研究探索了一种计算机辅助方法，用于开发具有高热稳定性和加工性能的 PBO。首先，采用材料基因组学方法设计了热固性苯并恶唑（CPBO）。随后，使用计算机辅助方法预测了它们的零剪切粘度、热失重 50% 时的温度、介电常数和介电损耗。最后，合成了两种经过筛选的热固性苯并恶唑，即 CPBO-1 和 CPBO-6，并进行了实验验证。实验表明，它们的熔点低于 100 ℃，最低熔体粘度分别为 0.5 Pa-s 和 1.5 Pa-s。相应的聚合物 pCPBO-1 和 pCPBO-6 具有很高的热稳定性。pCPBO-1 在氮气中的 5% 失重温度为 618.9 ℃，介电常数和介电损耗分别为 3.1 和 0.0063。对于热固性树脂来说，这些数值都非常出色。与传统的试错法相比，这种计算机辅助筛选方法更有效、更经济。

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引用次数: 0

CO2-based polyurethane elastomers with enhanced mechanical and tunable room-temperature damping performances 具有更强机械性能和可调室温阻尼性能的二氧化碳基聚氨酯弹性体

IF 5.8 2区化学 Q1 POLYMER SCIENCE

European Polymer Journal

Pub Date : 2024-10-11 DOI: 10.1016/j.eurpolymj.2024.113499

Elastomers provide excellent damping performance owing to their unique viscoelasticity, which are widely used as vibration and noise reduction materials. However, conventional rubber-based elastomers with a low glass transition temperature (T_g) and narrow damping range are difficult to adapt to room-temperature conditions. Additionally, most of petroleum-based elastomers hinder the sustainable development. In this work, a series of novel polyurethane elastomers was synthesized using carbon-fixed CO₂-based polycarbonate propylene diol (PPCD). The impact of hard segment (HS) content on the thermal, mechanical, and damping properties of CO₂-based polyurethane (PU) was comprehensively investigated. Increasing the HS content from 16 % to 44 % increased the T_g from −3.8 °C to 21.7 °C, covering the entire damping range at room temperature with an adjustable damping performance. Furthermore, the tensile strength increased from 7.2 MPa to 27.0 MPa. The synthesis of CO₂-based PU can propel the utilization of PU in damping applications, enabling sustainable advancement of the PU industry.

弹性体因其独特的粘弹性而具有出色的阻尼性能，被广泛用作减震降噪材料。然而，传统的橡胶基弹性体玻璃化转变温度（Tg）低，阻尼范围窄，难以适应室温条件。此外，大多数石油基弹性体阻碍了可持续发展。在这项研究中，利用固定碳的二氧化碳基聚碳酸酯丙二醇（PPCD）合成了一系列新型聚氨酯弹性体。该研究全面考察了硬质段（HS）含量对二氧化碳基聚氨酯（PU）的热性能、机械性能和阻尼性能的影响。将 HS 含量从 16% 提高到 44%，可将 Tg 从 -3.8 °C 提高到 21.7 °C，覆盖室温下的整个阻尼范围，且阻尼性能可调。此外，拉伸强度从 7.2 兆帕增加到 27.0 兆帕。二氧化碳基聚氨酯的合成可推动聚氨酯在阻尼应用中的使用，实现聚氨酯行业的可持续发展。

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引用次数: 0

Synthesis of linear and crosslinked isosorbide-containing poly(β-thioether ester) via amine-catalyzed thiol-Michael addition 通过胺催化硫醇-迈克尔加成法合成线性和交联的含异山梨醇的聚（β-硫醚酯

IF 5.8 2区化学 Q1 POLYMER SCIENCE

European Polymer Journal

Pub Date : 2024-10-11 DOI: 10.1016/j.eurpolymj.2024.113498

In this work, the amine-catalyzed thiol-Michael reaction of isosorbide or isomannide-derived dithiols as Michael-donors, with some diacrylates and dimethacrylates as Michael-acceptors, is reported. In a first part, different amines (1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU), dimethylaminopyridine (DMAP), Amberlyst® A-21 and hexylamine (HA)) were tested as catalysts for reactions involving diacrylates and dimethacrylates in acetonitrile, respectively. Molecular weight taken as the relevant criterion, DBU and DMAP were found to be equally efficient for polymerization with acrylates while DBU was the most efficient one with methacrylates. A library of polymers differing from the structure of the used diacrylate (some of them derived from isosorbide or isomannide) or dimethacrylate was prepared, with fair molecular weights and Tg varying from –22 to +32 °C. Then oligomers with controlled molecular weight and good end group fidelity were prepared, and were further used in a two-stage crosslinking reaction to prepare soft and elastic biobased crosslinked polymers via thiol-Michael addition.

在这项工作中，报告了异山梨醇或异山梨醇衍生的二硫醇作为迈克尔供体与一些二丙烯酸酯和二甲基丙烯酸酯作为迈克尔受体在胺催化下发生的硫醇-迈克尔反应。在第一部分中，测试了不同胺类（1,8-二氮杂双环[5.4.0]十一-7-烯（DBU）、二甲氨基吡啶（DMAP）、Amberlyst® A-21 和己胺（HA））作为催化剂，分别用于二丙烯酸酯和二甲基丙烯酸酯在乙腈中的反应。以分子量作为相关标准，发现 DBU 和 DMAP 与丙烯酸酯的聚合效率相同，而 DBU 与甲基丙烯酸酯的聚合效率最高。我们制备了与所用二丙烯酸酯（其中一些来自异山梨醇或异芒硝）或二甲基丙烯酸酯结构不同的聚合物库，这些聚合物的分子量适中，Tg 值在 -22 至 +32 °C 之间。然后制备出分子量可控、端基保真度高的低聚物，并进一步用于两阶段交联反应，通过硫醇-迈克尔加成法制备出柔软而富有弹性的生物基交联聚合物。

引用次数: 0

Synthesis of alternating polyesters using a dual catalytic system of alkali metal alkoxides and crown ether 使用碱金属烷氧基化合物和冠醚双重催化体系合成交替聚酯

IF 5.8 2区化学 Q1 POLYMER SCIENCE

European Polymer Journal

Pub Date : 2024-10-11 DOI: 10.1016/j.eurpolymj.2024.113497

In this study, a dual catalytic system that merges crown ether with alkali metal alkoxides (AMA) is utilized in the ring-opening alternating polymerization (ROAP) of phthalic anhydride (PA) and propylene oxide (PO). This method streamlines the production of polyesters characterized by a fully alternating sequence, a modifiable molar mass (achieving up to 59.3 kg mol⁻¹), and a narrow molar mass distribution (Ð_M < 1.26). Analysis of various commercially available AMAs, notably sodium ethoxide (EtONa), sodium methoxide, and lithium ethoxide, in tandem with crown ethers (15-crown-5 and 18-crown-6), underscores the superior catalytic efficacy of the EtONa and 18-crown-6 pairing. This heightened efficiency is attributed to the coordination of crown ether with alkali metal ions, thereby boosting the nucleophilicity of terminal alkoxide anions. The methodology has been successfully deployed in the ROAP of PA, norbornene anhydride, and multiple epoxides, while also simplifying the creation of aliphatic–aromatic block polyesters from a mixture of PA, PO, and lactide. This strategy presents a straightforward approach to polyester production, thus making significant contributions to the evolution of polyester synthesis technology.

本研究在邻苯二甲酸酐（PA）和环氧丙烷（PO）的开环交替聚合（ROAP）中采用了冠醚与碱金属烷氧基化合物（AMA）的双催化体系。这种方法简化了聚酯的生产过程，其特点是序列完全交替、摩尔质量可调（最高可达 59.3 kg mol-1）以及摩尔质量分布窄（ÐM <1.26）。对各种市售 AMAs（特别是乙醇钠 (EtONa)、甲醇钠和乙醇锂）与冠醚（15-冠醚-5 和 18-冠醚-6）进行的分析表明，EtONa 和 18-冠醚-6 配对具有更高的催化效率。效率的提高归功于冠醚与碱金属离子的配位，从而增强了末端氧化烷阴离子的亲核性。该方法已成功应用于 PA、降冰片烯酐和多种环氧化物的 ROAP，同时还简化了从 PA、PO 和内酯混合物中生成脂肪族芳香族嵌段聚酯的过程。该策略提供了一种直接的聚酯生产方法，从而为聚酯合成技术的发展做出了重大贡献。

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引用次数: 0

Photo and pH dual stimuli-responsive block copolymer micelles with defined incorporation of o-nitrobenzyl units in poly(ɛ-caprolactone) block for controlled release 在聚(ɛ-己内酯)嵌段中明确加入邻硝基苄基单元的光和 pH 双刺激响应嵌段共聚物胶束用于控释

IF 5.8 2区化学 Q1 POLYMER SCIENCE

European Polymer Journal

Pub Date : 2024-10-10 DOI: 10.1016/j.eurpolymj.2024.113501

A series of dual stimuli-responsive block copolymers with varying content of photocleavable o-nitrobenzyl (ONB) ester group pendent in the hydrophobic poly(ɛ-caprolactone) block and pH-cleavable acetal linkage at the junction with hydrophilic poly(ethylene glycol) block is synthesized. The hydrophobic block is a random copolymer synthesized by ring-opening copolymerization of ɛ-caprolactone and ONB-substituted ɛ-caprolactone containing varying compositions of the two monomers. Kinetics of polymerization shows that ONB-functionalized monomer has lower reactivity than that of the unsubstituted monomer. The series of block copolymers shows self-assembly into well-defined spherical micelles of average size of 150–200 nm in aqueous solution. Photocleavage of ONB groups is studied by NMR and UV–vis spectroscopy, and its extent is determined. The two stimuli viz. UV light and pH are used individually as well as simultaneously to study the controlled release of the encapsulated drug Camptothecin and the synergistic effect of the two stimuli is demonstrated. The effect of varying content of ONB groups is observed on drug release profile. MTT assay showed non-cytotoxic nature of the polymer. Cell uptake and photoinduced release of doxorubicin (DOX) from the micelles in MDA-MB-231 cells is demonstrated.

我们合成了一系列双刺激响应嵌段共聚物，它们的疏水性聚（ɛ-己内酯）嵌段中悬垂有不同含量的可光裂解邻硝基苄基（ONB）酯基，而在与亲水性聚（乙二醇）嵌段的连接处则存在可通过 pH 值裂解的缩醛连接。疏水嵌段是由ɛ-己内酯和 ONB 取代的ɛ-己内酯开环共聚合成的无规共聚物，两种单体的成分各不相同。聚合动力学表明，ONB 功能化单体的反应活性低于未取代单体。该系列嵌段共聚物在水溶液中能自组装成平均尺寸为 150-200 纳米的界限分明的球形胶束。通过核磁共振和紫外-可见光谱研究了 ONB 基团的光解作用，并确定了其程度。紫外线和 pH 值这两种刺激既可单独使用，也可同时使用，用于研究封装药物喜树碱的控制释放，并证明了这两种刺激的协同效应。观察了不同含量的 ONB 组对药物释放曲线的影响。MTT 试验表明聚合物无细胞毒性。实验证明了 MDA-MB-231 细胞对多柔比星（DOX）的吸收以及光诱导胶束对多柔比星（DOX）的释放。

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引用次数: 0

The influence of Fe2+ on the self-assembly of a bipyridine containing homopolymer: From bowl-shaped nanoparticles to vesicles Fe2+对含双吡啶均聚物自组装的影响：从碗状纳米颗粒到囊泡

IF 5.8 2区化学 Q1 POLYMER SCIENCE

European Polymer Journal

Pub Date : 2024-10-10 DOI: 10.1016/j.eurpolymj.2024.113502

Metal ion coordination has critical influence on the self-assembly behavior of amphiphilic polymers and the morphology of the obtained assemblies. Herein, an amphiphilic homopolymer with 2,2′-bipyridine (BPy) as side chain is synthesized (noted as PBPyAA), which can self-assemble into bowl-shaped nanoparticles (BNPs) in tetrahydrofuran (THF)/water. Taking advantage of the coordination interaction between BPy and metal ions, Fe²⁺ is chosen to regulate the self-assembly behavior and the morphology of the assemblies of PBPyAA in two pathways. (Ⅰ) The aqueous solution of Fe²⁺ with various concentrations is added to the THF solution of PBPyAA during self-assembly. (Ⅱ) Fe²⁺ is added into the THF solution of PBPyAA before self-assembly, followed by the addition of deionized water to promote the self-assembly. The results show that the pathway Ⅰ facilitates the coordination of BPy and Fe²⁺. With the increase of the concentration of Fe²⁺ aqueous solution, the coordination efficiency of BPy increases from 0.419 % to 7.789 %, leading to the transformation of BNPs to vesicles. Though the coordination efficiency of BPy also increases with the concentration of Fe²⁺ in pathway Ⅱ, which is still quite low of 0.274 % to 0.366 %, and the morphology of the BNPs barely changes. In addition, ethylene diamine tetraacetic acid (EDTA), a strong chelating agent, is also added to promote the competitive complexation with BPy, resulting in the dissociation of BPy and Fe²⁺ and the reversible transformation from vesicles to BNPs. Overall, the effect of Fe²⁺ coordination on the self-assembly behavior of PBPyAA in two pathways is investigated and the reversible transformation of BNPs to vesicles is also achieved.

金属离子配位对两亲性聚合物的自组装行为和所获得的组装体的形态具有重要影响。本文合成了一种以 2,2′-联吡啶（BPy）为侧链的两亲性均聚物（简称 PBPyAA），它能在四氢呋喃（THF）/水中自组装成碗状纳米颗粒（BNPs）。利用 BPy 与金属离子之间的配位相互作用，选择 Fe2+ 通过两种途径调节 PBPyAA 的自组装行为和组装体的形态。(Ⅰ)在自组装过程中向 PBPyAA 的 THF 溶液中加入不同浓度的 Fe2+ 水溶液。(Ⅱ) 在自组装前向 PBPyAA 的 THF 溶液中加入 Fe2+，然后加入去离子水促进自组装。结果表明，通路Ⅰ促进了 BPy 和 Fe2+ 的配位。随着 Fe2+ 水溶液浓度的增加，BPy 的配位效率从 0.419 % 增加到 7.789 %，从而导致 BNPs 转化为囊泡。虽然 BPy 的配位效率也随着通路Ⅱ中 Fe2+ 浓度的增加而增加，但仍然很低，仅为 0.274 % 至 0.366 %，而且 BNPs 的形态几乎没有变化。此外，还加入了强螯合剂乙二胺四乙酸（EDTA），以促进与 BPy 的竞争性络合，从而使 BPy 与 Fe2+ 解离，并从囊泡可逆地转变为 BNPs。总之，通过两种途径研究了 Fe2+ 配位对 PBPyAA 自组装行为的影响，并实现了 BNPs 向囊泡的可逆转化。

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引用次数: 0

Metal–phenolic nanozyme based microneedle patch with antibacterial and antioxidant for infected wound healing 基于金属酚类纳米酶的微针贴片具有抗菌和抗氧化作用，可促进感染伤口愈合

IF 5.8 2区化学 Q1 POLYMER SCIENCE

European Polymer Journal

Pub Date : 2024-10-10 DOI: 10.1016/j.eurpolymj.2024.113500

Chronic bacterial-infected wound healing is becoming increasingly severe, with high rates of mortality and disability, owing to bacterial film, excessive accumulation of reactive oxygen species (ROS), inflammatory, and traditional therapeutics with poor drug permeability. Herin, a functional Zn-gallic acid nanozyme (Zn-NM) with excellent antibacterial and antioxidant capacity was incorporated with a gelatin-based microneedle patch (Zn-NM@MN) to achieve transdermal and sustained release of the drug at the infected wound site. The Zn-NM displayed the concentration-dependent antibacterial capacity, and 250 μg/mL of Zn-NM simultaneously possessed excellent antibacterial (89.36 ± 0.95 % for Escherichia coli, 92.44 ± 11.03 % for Staphylococcus aureus, and 95.03 ± 1.06 % for Methicillin-resistant Staphylococcus aureus), antioxidant properties and negligible cytotoxicity. After that, Zn-NM@MN could transdermal the epidermis or biofilm to sustain the release of Zn-NM for 3 h (release of 80 % drug). Systematic tissue regeneration assessment on rats’ infected full-thickness skin wounds demonstrated an enhanced wound healing rate. Zn-NM@MN could efficiently kill the bacteria (about 85 %), alleviate oxidant stress, reduce bacterial-induced inflammation, and promote vascular regeneration. This synergetic therapy strategy will pave the way for treating complicated infection wounds.

由于细菌薄膜、活性氧（ROS）过度积累、炎症以及药物渗透性差的传统疗法，慢性细菌感染伤口愈合日益严重，死亡率和致残率居高不下。Herin是一种具有优异抗菌和抗氧化能力的功能性锌-胆酸纳米酶（Zn-NM），它与明胶基微针贴片（Zn-NM@MN）相结合，实现了药物在感染伤口部位的透皮和持续释放。Zn-NM 具有浓度依赖性抗菌能力，250 μg/mL 的 Zn-NM 同时具有优异的抗菌性（对大肠杆菌的抗菌率为 89.36 ± 0.95 %，对金黄色葡萄球菌的抗菌率为 92.44 ± 11.03 %，对耐甲氧西林金黄色葡萄球菌的抗菌率为 95.03 ± 1.06 %）、抗氧化性和可忽略的细胞毒性。之后，Zn-NM@MN 可透皮表皮或生物膜，使 Zn-NM 的释放持续 3 小时（释放 80% 的药物）。对大鼠受感染的全厚皮肤伤口进行的系统组织再生评估显示，伤口愈合率有所提高。Zn-NM@MN 能有效杀灭细菌（约 85%）、缓解氧化应激、减轻细菌引起的炎症反应并促进血管再生。这种协同治疗策略将为治疗复杂的感染伤口铺平道路。

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引用次数: 0