4种典型纳米材料对小鼠胚胎成纤维细胞毒性的初步研究

为探讨不同种类纳米材料对原代培养小鼠胚胎成纤维细胞(Mouse embryo fibroblasts,MEF)的毒性效应及作用机制,选择4种典型的纳米材料(纳米碳、单壁碳纳米管、纳米氧化锌、纳米二氧化硅)制备颗粒悬液,设立5个剂量组(5、10、20、50、100μg·mL-1)对BALB/c小鼠MEF细胞进行24、48、72h染毒培养,利用细胞形态学观察和噻唑蓝实验(MTT比色法)检测上述4种纳米材料对MEF细胞活性的影响,同时,测定染毒24h后细胞培养液上清中乳酸脱氢酶(LDH)活性以探讨纳米颗粒对细胞膜完整性的影响.结果显示:1)4种纳米材料均能明显影响MEF细胞的生长形态.染毒24h后,MEF细胞发生不同程度的回缩变形,细胞间隙增大,排列稀疏,胞内颗粒物增多,细胞透明度下降.2)纳米碳、纳米氧化锌、纳米二氧化硅对MEF细胞增殖的抑制作用和对细胞膜完整性的损伤作用均随染毒剂量的升高而增强,具有明显的剂量-效应关系,其半数致死浓度(24h-IC50)分别为21.85、21.94、461.10μg·mL-1;碳纳米管组的剂量-效应之间不呈对数线性关系,未能得出其24h-IC50.3)在不同染毒剂量水平上,4种纳米材料的毒性对比差异显著:低剂量水平上纳米碳与碳纳米管的毒性强于纳米氧化锌和纳米二氧化硅,随着剂量的升高纳米氧化锌的细胞毒性升高最为显著.结果提示,纳米材料能够对MEF细胞造成毒性损伤,破坏细胞膜的完整性可能只是作用途径之一;纳米材料的毒性可能受粒径、形状、化学组成等许多因素的影响.     

(Super)paramagnetic nanoparticles as platform materials for environmental applications: From synthesis to demonstration

• The fabrication of monodisperse, (super)paramagnetic nanoparticles is summarized. • Monolayer and bilayer surface coating structures are described. • Mono/bilayer coated nanoparticles showed high sorption capacities for U, As, and Cr. Over the past few decades, engineered, (super)paramagnetic nanoparticles have drawn extensive research attention for a broad range of applications based on their tunable size and shape, surface chemistries, and magnetic properties. This review summaries our recent work on the synthesis, surface modification, and environmental application of (super)paramagnetic nanoparticles. By utilizing high-temperature thermo-decomposition methods, first, we have broadly demonstrated the synthesis of highly monodispersed, (super)paramagnetic nanoparticles, via the pyrolysis of metal carboxylate salts in an organic phase. Highly uniform magnetic nanoparticles with various size, composition, and shape can be precisely tuned by controlled reaction parameters, such as the initial precursors, heating rate, final reaction temperature, reaction time, and the additives. These materials can be further rendered water stable via functionalization with surface mono/bi-layer coating structure using a series of tunable ionic/non-ionic surfactants. Finally, we have demonstrated platform potential of these materials for heavy metal ions sensing, sorption, and separation from the aqueous phase.     

TiO2纳米粉体材料的制备及其脱除Hg蒸气污染物的研究

燃煤电站产生的汞污染物,是最难控制的巨毒、痕量污染物之一,已引起国内外广泛的研究兴趣.通过液相法制备了两种TiO2纳米粉体材料,对其结构和形貌采用TEM、BET和XRD进行了表征测试,在固定床反应器条件下初步测定了TiO2纳米粉体对单质汞Hg0污染物的脱除效果,研究表明,脱除效率随温度的升高而增加,最高可达60%.     

Metabolites change of Scenedesmus obliquus exerted by AgNPs

With increasing emission of silver nanoparticles (AgNPs) into the environment, it is important to understand the effects of ambient concentration of AgNPs. The biological effects of AgNPs on Scenedesmus obliquus, a ubiquitous freshwater microalgae, was evaluated. AgNPs exerted a minor inhibitory effect at low doses. Non-targeted metabolomic studies were conducted to understand and analyze the effect of AgNPs on algal cells from a molecular perspective. During the 48?hr of exposure to AgNPs, 30 metabolites were identified, of which nine had significant changes compared to the control group. These include d-galactose, sucrose, and d-fructose. These carbohydrates are involved in the synthesis and repair of cell walls. Glycine, an important constituent amino acid of glutathione, increased with AgNP exposure concentration increasing, likely to counteract an increased intracellular oxidative stress. These results provide a new understanding of the toxicity effects and mechanism of AgNPs. These metabolites could be useful biomarkers for future research, employed in the early detection of environmental risk from AgNPs.     

Microwave-assisted synthesized zinc nanoparticles attenuate cisplatin-induced testicular toxicity in mice

Abstract

The purpose of this study was to investigate the protective effects of zinc nanoparticles against cisplatin-induced testicular toxicity in mice. Zinc nanoparticles were produced by microwave-assisted synthesis using Lavandula vera extract as reducing agent. Single doses of cisplatin (7?mg/kg, intraperitoneally) and ZnSO₄ (10?mg/kg, orally), and various doses of zinc nanoparticles (10???50?mg/kg, orally) and vitamin E (100?mg/kg, interaperitoneally) were administered. The protective role of zinc nanoparticles was determined biochemically and histologically. Gradual reduction in malondialdehyde levels and elevation in glutathione levels and in the activities of superoxide dismutase and catalase upon administration of zinc nanoparticles were observed. The pathology of mice treated with cisplatin/vitamin E and cisplatin/zinc nanoparticles were apparently equal, but vitamin E treatment was more effective in lowering oxidative stress markers than zinc nanoparticles. These findings suggest that co-administration of zinc nanoparticles with cisplatin could prevent adverse effects on the male reproductive system via their potential antioxidant properties.     

纳米Fe3O4的制备及其对对硝基甲苯的催化降解

采用共沉淀法制备了纳米四氧化三铁（Fe3O4），并进行必要表征，制备所得的Fe3O4粒径与商品Fe3O4相当，均为15～20nm。在中性、碱性条件下，制备的材料表面带负电，而在弱酸性条件下，则带正电。制备出的Fe3O4与商品的Fe3O4一样，对对硝基甲苯具有相同的机械催化降解效率，均符合准一级反应动力学。     

Synthesis of Li-doped bismuth oxide nanoplates,Co nanoparticles modification,and good photocatalytic activity toward organic pollutants

Abstract

Lithium-doped bismuth oxide nanoplates with the thickness of 50–150?nm and tetragonal bismuth oxide, monoclinic lithium bismuthate phases have been synthesized via a simple hydrothermal process using lithium acetate and sodium bismuthate as the raw materials. Cobalt nanoparticles modified lithium-doped bismuth oxide nanoplates hybrids were obtained by an in situ photo-deposition route. The cobalt nanoparticles-modified nanoplates hybrids display significantly enhanced photocatalytic activity toward gentian violet compared with the nanoplates. Gentian violet solution can be totally degraded by the hybrids within 60?min under ultraviolet–visible light irradiation. The superior photocatalytic activity of the cobalt nanoparticles modified nanoplates hybrids originates from the superior charge transfer capacity and the energy band structure of the hybrids. The excellent photocatalytic performance makes the cobalt nanoparticles modified nanoplates hybrids a promising candidate as the photocatalyst for wastewater treatment.     

掺入金属离子的TiO2纳米粒子光催化降解吖啶橙

利用酸催化溶胶－凝胶法（ｓｏｌ－ｇｅｌ）制备了 Ｆｅ３＋和 Ｃｒ３＋不同掺入量的 ＴｉＯ２半导体纳米粒子研究了这些纳米粒子对吖啶橙光催化氧化降解的影响．结果表明，微量 Ｆｅ３＋和 Ｃｒ３＋的掺入可明显提高 ＴｉＯ２的光催化活性．进一步研究表明，在 Ｆｅ３＋－ＴｉＯ２体系中，最佳掺入量为 ０．１％，而且中性介质和自然光有利于光催化氧化反应的进行，反应３ｈ后降解率可达９７．７５％．在Ｃｒ３＋－ＴｉＯ２体系中，弱碱性介质和自然光有利于光催化氧化反应，最佳掺入量为０．０５％，降解率可达８７．５４％．     

纳米氢氧化镁改性PVDF超滤膜的制备与表征

通过相转化法制备了纳米PVDF/Mg(OH)_2共混超滤膜,研究了负载Mg(OH)_2对PVDF膜结构和性能的影响。以牛血清蛋白(BSA)为模拟污染物进行超滤试验,测试膜的纯水通量和截留率;测定膜表面和水之间的接触角,进而定量分析比较膜表面的亲水性;利用微机电子控制万能试验机测试膜的机械性能;通过扫描电镜(SEM)、原子力显微镜(AFM)、X射线衍射仪(XRD)等方法表征膜表面特征。结果表明,添加纳米Mg(OH)_2的改性膜保持了原有膜的晶型结构,证明纳米Mg(OH)_2与PVDF材料有很好的相容效果。当纳米Mg(OH)_2添加量为0.8%(质量分数)时,改性效果达到最优。此时,接触角从73.1°降至59.6°,纯水通量为333.37 L/(m~2·h),较未改性前提高了126.3%,膜的拉伸最大力为6.8 N,断裂伸长率为16.2%,较未改性膜的机械性能有明显提高,膜的抗污染性也显著提高。