Preparation of rare earth two-dimensional nano-thin film using PET as carrier

Micro & nano letters

article

Jiaxin Wang¹  Junwei Li¹  Min Zhang²  Baohang Zhang¹  Zhehui Li¹  Yuting Wang¹  Yulong Wu¹  Qianjin Zhang¹  Wanxiang Yao¹ 

[1] School of Materials Science and Engineering, Tianjin Chengjian University;Department of Scientific Research, Logistics University of Chinese People's Armed Police Forces

关键词: precipitation (physical chemistry);    nanostructured materials;    thin films;    nanofabrication;    scanning electron microscopy;    X-ray chemical analysis;    polyethylene terephthalate;    PET;    structurally ordered rare earth two-dimensional nano-thin film;    homogeneous precipitation method;    reaction temperature;    reaction time;    reactant concentration;    scanning electron microscopy;    energy dispersive spectrometry;    optimal micromorphology;    gas–liquid surface;    temperature 85 degC;    time 24 h;   

DOI  :  10.1049/mnl.2017.0570

学科分类：计算机科学（综合）

来源: Wiley

【 摘 要 】

Background:  Plants are new sources of antibacterial agents, hence the need to determine and evaluate the antibacterial properties, antioxidant activity and gas chromatography – mass spectrometer (GC-MS) profile of medicinal plants.   Methodology:  In this study, sequential extraction of  Prunus africana  and  Harrisonia abyssinica  was used to obtain ethyl acetate and methanol extracts. Antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), whereas the total phenolic and total flavonoid contents were estimated using Folin-Ciocalteu and aluminium chloride, respectively. Antibacterial properties of the extracts against  Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli and  Candida albicans  were estimated using the disc diffusion method and compared against streptomycin.   Results:  Screening of crude methanolic extracts revealed the presence of secondary metabolites which was further confirmed by Fourier transform infrared (FT-IR) characterisation that revealed the presence of H-bonded OH functional groups. The extracts revealed that  P. africana  had a higher total phenolic and total flavonoid contents compared to  H. abyssinica . Methanolic extracts of both plants had moderate activity against selected microorganisms and both inhibited DPPH radical scavenging activity. GC-MS analysis of  P. africana  and  H. abyssinica  extracts revealed the presence of several phytochemicals that have been reported to have medicinal uses. Total phenolic and flavonoid contents showed positive correlations with the DPPH radical scavenging activity and negative correlations with EC 50 .   Conclusion:   Prunus africana  and  H. abyssinica  extracts had moderate antimicrobial properties against the selected microorganisms because of the presence of secondary metabolites.

【 授权许可】

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