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Preparation and Characterization of Core/Shell-type Ag/Chitosan Nanoparticles with Antibacterial Activity

  • Lin, Yue;Jing, Wang;Kang, Pan;Xiaoming, Zhang;Zhouping, Wang;Wenshui, Xia
    • Bulletin of the Korean Chemical Society
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    • v.32 no.4
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    • pp.1277-1281
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    • 2011

  • Making use of chitosan (CS) and ethylenediaminetetraacetic acid (EDTA) as a reaction system, CS-EDTA nanoparticles were synthesized through a facile counterion complex coacervation method. $Ag^+$ could enter porous CS nanoparticles synthesized with this method, allowing Ag nanoparticles within chitosan nanoparticles were synthesized by reducing silver nitrate with chitosan. Because of the noncovalent interaction between CS and EDTA, the EDTA could be easily removed via dialysis against water, and pure core/shell-type Ag/CS nanoparticles could be obtained. The nanoparticles showed higher antibacterial activity toward E. coli than the active precursor Ag nanoparticles and CS.

  • https://doi.org/10.5012/bkcs.2011.32.4.1277 인용 PDF KSCI

Concentration optimization of Tb/Yb co-doped alumino-germanosilicate optical fiber for upconversion visible laser applications

  • Lin, Aoxiang;Watekar, Pramod R.;Liu, Xueming;Cho, Hye-Jin;Chung, Young-Joo;Han, Won-Taek
    • Proceedings of the Optical Society of Korea Conference
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    • 2008.02a
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    • pp.249-250
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    • 2008

  • We report on the visible photoluminescence of the Tb/Yb co-doped alumino-germano-silicate fibers for visible fiber laser application. By changing the concentration ratios of $Tb^{3+}$ to $Yb^{3+}$, we optimized the solution doping conditions and obtained the highest emission efficiency at 546nm. The luminescence intensity at 546nm was found to increase with the relative increase of $Tb^{3+}$ ions.

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