Tejero Rubén, Gutiérrez Beatriz, López Daniel, López-Fabal Fátima, Gómez-Garcés José L, Fernández-García Marta
Instituto de Ciencia y Tecnología de Polímeros (ICTP-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain.
Instituto de Ciencia y Tecnología de Polímeros (ICTP-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain.
Acta Biomater. 2015 Oct;25:86-96. doi: 10.1016/j.actbio.2015.07.037. Epub 2015 Jul 26.
A series of six copolymeric families, P(AN-co-MTAs) with various molar fractions of acrylonitrile (fAN) and methacrylates (fMTA) based on 1,3-thiazole and 1,2,3-triazole pendant groups with several spacers of different length and nature (alkyl or succinic), have been synthesized by conventional radical polymerization. The molar fraction of acrylonitrile in the copolymers (FAN) was determined by CHNS elemental analysis. The copolymers were also characterized by ATR-FTIR and molecular weights were determined by size exclusion chromatography (SEC). Due to the nucleophilic nature of the azole heterocycles the copolymers have been easily modified by N-alkylation reaction with butyl iodide leading to polyelectrolytes of diverse amphiphilic balance, P(AN-co-MTAs-BuI). The degree of quaternization (DQ) was quantitative in all instances and was determined by (1)H NMR spectroscopy. Dynamic light scattering (DLS) measurements were performed in order to determine the particle size and the charge density of the systems. The antimicrobial activity of the copolymers was studied in terms of minimal inhibitory concentration (MIC) against the Gram-positive bacteria Staphylococcus aureus, the Gram-negative Pseudomonas aeruginosa and the yeast Candida parapsilosis, as well as the cytotoxic activity toward human red blood cells (RBCs). These types of amphiphilic copolycations presented high selectivity (>300) maintaining moderate to good antimicrobial activity (MIC=4-64 μg/mL) and being non-hemolytic even at high molar fractions of AN in the copolymers compared to PMTAs-BuI homopolymers. Moreover, two examples of acrylonitrile-enriched copolymers (FAN=0.6) presented an excellent time-killing efficiency against microorganisms with 99.9% of killing ranging from 5 to 30 min. Besides, important changes in the morphology of the cell envelop of the microorganisms after treatment with P(AN-co-MTAs) were observed by Field Emission Scanning Electron Microscopy (FE-SEM) compared to untreated samples. These results indicate that these quaternized copolymers (QUATs) behave like the corresponding PMTAs-BuI homopolymers, being microbiostatic and also highly effective microbiocidal agents.
通过常规自由基聚合反应合成了一系列六个共聚物家族，即具有不同丙烯腈（fAN）和甲基丙烯酸酯（fMTA）摩尔分数的P（AN-co-MTAs），这些共聚物基于1,3-噻唑和1,2,3-三唑侧基，并带有几种不同长度和性质（烷基或琥珀酸基）的间隔基。共聚物中丙烯腈的摩尔分数（FAN）通过CHNS元素分析确定。这些共聚物还通过衰减全反射傅里叶变换红外光谱（ATR-FTIR）进行了表征，分子量通过尺寸排阻色谱法（SEC）测定。由于唑杂环的亲核性质，这些共聚物很容易通过与碘化丁烷的N-烷基化反应进行改性，从而得到具有不同两亲平衡的聚电解质P（AN-co-MTAs-BuI）。季铵化程度（DQ）在所有情况下都是定量的，并通过核磁共振氢谱（¹H NMR）光谱法测定。进行动态光散射（DLS）测量以确定体系的粒径和电荷密度。研究了共聚物对革兰氏阳性菌金黄色葡萄球菌、革兰氏阴性菌铜绿假单胞菌和酵母近平滑念珠菌的最小抑菌浓度（MIC）方面的抗菌活性，以及对人红细胞（RBC）的细胞毒性活性。与PMTAs-BuI均聚物相比，这类两亲性共聚阳离子具有高选择性（>300），保持中等至良好的抗菌活性（MIC = 4 - 64 μg/mL），即使在共聚物中AN的摩尔分数较高时也不具有溶血作用。此外，两个富含丙烯腈的共聚物实例（FAN = 0.6）对微生物具有优异的杀菌效率，5至30分钟内杀灭率达99.9%。此外，与未处理的样品相比，通过场发射扫描电子显微镜（FE-SEM）观察到用P（AN-co-MTAs）处理后微生物细胞膜形态发生了重要变化。这些结果表明，这些季铵化共聚物（QUATs）的行为与相应的PMTAs-BuI均聚物相似，既是抑菌剂也是高效杀菌剂。
