PDF(Pubmed)
Abstract：
The purpose of this study was to investigate the antimicrobial activity of citrate-stabilized sols of cerium oxide nanoparticles at different concentrations via different microbiological methods and to compare the effect with the peroxidase activity of nanoceria for the subsequent development of a regeneration-stimulating medical and/or veterinary wound-healing product providing new types of antimicrobial action. The object of this study was cerium oxide nanoparticles synthesized from aqueous solutions of cerium (III) nitrate hexahydrate and citric acid (the size of the nanoparticles was 3-5 nm, and their aggregates were 60-130 nm). Nanoceria oxide sols with a wide range of concentrations (10-1-10-6 M) as well as powder (the dry substance) were used. Both bacterial and fungal strains (Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Proteus vulgaris, Candida albicans, Aspergillus brasielensis) were used for the microbiological studies. The antimicrobial activity of nanoceria was investigated across a wide range of concentrations using three methods sequentially; the antimicrobial activity was studied by examining diffusion into agar, the serial dilution method was used to detect the minimum inhibitory and bactericidal concentrations, and, finally, gas chromatography with mass-selective detection was performed to study the inhibition of E. coli\'s growth. To study the redox activity of different concentrations of nanocerium, we studied the intensity of chemiluminescence in the oxidation reaction of luminol in the presence of hydrogen peroxide. As a result of this study\'s use of the agar diffusion and serial dilution methods followed by sowing, no significant evidence of antimicrobial activity was found. At the same time, in the current study of antimicrobial activity against E. coli strains using gas chromatography with mass spectrometry, the ability of nanoceria to significantly inhibit the growth and reproduction of microorganisms after 24 h and, in particular, after 48 h of incubation at a wide range of concentrations, 10-2-10-5 M (48-95% reduction in the number of microbes with a significant dose-dependent effect) was determined as the optimum concentration. A reliable redox activity of nanoceria coated with citrate was established, increasing in proportion to the concentration, confirming the oxidative mechanism of the action of nanoceria. Thus, nanoceria have a dose-dependent bacteriostatic effect, which is most pronounced at concentrations of 10-2-10-3 M. Unlike the effects of classical antiseptics, the effect was manifested from 2 days and increased during the observation. To study the antimicrobial activity of nanomaterials, it is advisable not to use classical qualitative and semi-quantitative methods; rather, the employment of more accurate quantitative methods is advised, in particular, gas chromatography-mass spectrometry, during several days of incubation.
摘要：
这项研究的目的是通过不同的微生物方法研究不同浓度的柠檬酸盐稳定的氧化铈纳米颗粒溶胶的抗微生物活性，并比较纳米二氧化铈的过氧化物酶活性的影响，用于随后开发刺激再生的医疗和/或兽医伤口愈合产品，提供新型的抗微生物作用。本研究的对象是由六水合硝酸铈（III）和柠檬酸的水溶液合成的氧化铈纳米颗粒（纳米颗粒的尺寸为3-5nm，它们的聚集体为60-130nm)。使用浓度范围很广的纳米氧化铈溶胶（10-1-10-6M）以及粉末（干物质）。细菌和真菌菌株（枯草芽孢杆菌，蜡样芽孢杆菌,金黄色葡萄球菌,铜绿假单胞菌,大肠杆菌,普通变形杆菌,白色念珠菌,巴西曲霉）用于微生物学研究。依次使用三种方法在很宽的浓度范围内研究了纳米二氧化铈的抗菌活性；通过检查扩散到琼脂中研究了抗菌活性，采用系列稀释法检测最低抑菌和杀菌浓度,and,最后,采用质量选择检测的气相色谱来研究大肠杆菌生长的抑制作用。为了研究不同浓度纳米铈的氧化还原活性,我们研究了在过氧化氢存在下鲁米诺氧化反应中的化学发光强度。作为本研究的结果，使用琼脂扩散和连续稀释方法，然后播种，没有发现抗菌活性的显著证据.同时,在目前使用气相色谱-质谱联用技术对大肠杆菌菌株的抗菌活性研究中，24小时后纳米氧化铈显著抑制微生物生长和繁殖的能力，特别是,在宽范围的浓度下孵育48小时后，将10-2-10-5M(具有显著剂量依赖性效应的微生物数量减少48-95%)确定为最佳浓度。建立了柠檬酸盐包覆的纳米氧化铈的可靠氧化还原活性，与浓度成比例增加，证实了纳米二氧化铈作用的氧化机制。因此，纳米铈具有剂量依赖性的抑菌作用，这在10-2-10-3M的浓度下最明显。与经典防腐剂的效果不同，效果从2天开始显现，并在观察期间增加。为研究纳米材料的抗菌活性,建议不要使用经典的定性和半定量方法；相反，建议采用更准确的定量方法，特别是,气相色谱-质谱,在几天的孵化过程中。
