title: Green synthesis of chondroitin sulfate-capped silver nanoparticles: characterization and surface modification.
abstract: A one-step route for the green synthesis of highly stable and nanosized silver metal particles with narrow distribution is reported. In this environmentally friendly synthetic method, silver nitrate was used as silver precursor and biocompatible chondroitin sulfate (ChS) was used as both reducing agent and stabilizing agent. The reaction was carried out in a stirring aqueous medium at the room temperature without any assisted by microwave, autoclave, laser irradiation, γ-ray irradiation or UV irradiation. The transparent colorless solution was converted to the characteristics light red then deep red-brown color as the reaction proceeds, indicating the formation of silver nanoparticles (Ag NPs). The Ag NPs were characterized by UV-visible spectroscopy (UV-vis), photon correlation spectroscopy, laser Doppler anemometry, transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR). The results demonstrated that the obtained metallic nanoparticles were Ag NPs capped with ChS. In this report, dynamic light scattering (DLS) was used as a routinely analytical tool for measuring size and distribution in a liquid environment. The effects of the reaction time, reaction temperature, concentration and the weight ratio of ChS/Ag+ on the particle size and zeta potential were investigated. The TEM image clearly shows the morphology of the well-dispersed ChS-capped Ag NPs are spherical in shape, and the average size (<20 nm) is much smaller than the Z-average value (76.7 nm) measured by DLS. Meanwhile, the ChS-capped Ag NPs coated with N-[(2-hydroxy-3-trimethylammonium) propyl] chitosan chloride (HTCC) were prepared by an ionic gelation method and the surface charge of Ag NPs was switched from negative to positive.
authors.affiliation: Institute of Preventive Medicine, National Defense Medical Center, PO Box 90048-700, Sanhsia, New Taipei City 237, Taiwan, ROC.
authors.forename: Kuang-ming
authors.initials: KM
authors.lastname: Cheng
authors.affiliation: Institute of Preventive Medicine, National Defense Medical Center, PO Box 90048-700, Sanhsia, New Taipei City 237, Taiwan, ROC.
authors.forename: Yao-wen
authors.initials: YW
authors.lastname: Hung
authors.affiliation: Institute of Preventive Medicine, National Defense Medical Center, PO Box 90048-700, Sanhsia, New Taipei City 237, Taiwan, ROC; Department of Food Science, National Taiwan Ocean University, 2 Pei-Ning Road, Keelung 20224, Taiwan, ROC.
authors.forename: Cheng-cheung
authors.initials: CC
authors.lastname: Chen
authors.affiliation: Institute of Preventive Medicine, National Defense Medical Center, PO Box 90048-700, Sanhsia, New Taipei City 237, Taiwan, ROC.
authors.forename: Cheng-che
authors.initials: CC
authors.lastname: Liu
authors.affiliation: Institute of Preventive Medicine, National Defense Medical Center, PO Box 90048-700, Sanhsia, New Taipei City 237, Taiwan, ROC. Electronic address: jjyoung@ms49.hinet.net.
authors.forename: Jenn-jong
authors.initials: JJ
authors.lastname: Young
mesh_terms: D002809:Chondroitin Sulfates / Q000737:chemistry*; D055772:Green Chemistry Technology; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D012834:Silver / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D012834:Silver; D002809:Chondroitin Sulfates
keywords: Chemical reduction; Chondroitin sulfate; Dynamic light scattering; Green synthesis; N-[(2-hydroxy-3-trimethylammonium)propyl]chitosan chloride; Silver nanoparticles