Green synthesis and characterization of gelatin-based and sugar-reduced silver nanoparticles.

Advanced Materials and Nanotechnology Laboratory, Institute of Advanced Technology (ITMA), Universiti Putra Malaysia, Selangor, Malaysia.
International Journal of Nanomedicine (Impact Factor: 4.2). 01/2011; 6:569-74. DOI: 10.2147/IJN.S16867
Source: PubMed

ABSTRACT Silver nanoparticles (Ag-NPs) have been successfully prepared with simple and "green" synthesis method by reducing Ag(+) ions in aqueous gelatin media with and in the absence of glucose as a reducing agent. In this study, gelatin was used for the first time as a reducing and stabilizing agent. The effect of temperature on particle size of Ag-NPs was also studied. It was found that with increasing temperature the size of nanoparticles is decreased. It was found that the particle size of Ag-NPs obtained in gelatin solutions is smaller than in gelatin-glucose solutions, which can be related to the rate of reduction reaction. X-ray diffraction, ultraviolet-visible spectra, transmission electron microscopy, and atomic force microscopy revealed the formation of monodispersed Ag-NPs with a narrow particle size distribution.

  • [Show abstract] [Hide abstract]
    ABSTRACT: With the aim of developing appropriate scaffolds for tissue engineering to suppress the formation of biofilms, an effective one-pot process was applied in this study to produce scaffolds with inherent antibacterial activity. A new method to synthesize genipin-crosslinked gelatin/nanosilver scaffolds with “green” in situ formation of silver nanoparticles by heat treatment is presented in this paper. In this procedure, toxic solvents, reducing agents, and stabilizing agents are avoided. UV–visible absorption spectra of the synthesized gelatin/nanosilver solutions were obtained immediately and three months after the synthesis revealing the presence and high stability of the silver nanoparticles. The TEM of gelatin/nanosilver solutions showed silver particles with spherical shapes that were less than 5 nm in size. Interestingly, contact angle was found to increase from 80° to 125° with the increase in concentration of nanosilver in gelatin. All gelatin/nanosilver solutions showed antimicrobial activity against Staphylococcus aureus and Escherichia coli. However, only the highest concentration showed antifungal effects against Candida albicans pathogens. Scaffolds were prepared by a lyophilization technique from this solution and their antimicrobial activities were examined. Introducing this facile green one-pot process of synthesizing scaffolds with antimicrobial and anti-biofilm properties may lead to key applications in tissue engineering techniques.
    Materials Science and Engineering: C. 01/2014; 39:235–244.
  • [Show abstract] [Hide abstract]
    ABSTRACT: We herein report the green synthesis of highly monodispersed, water soluble, stable and smaller sized dextrose reduced gelatin capped-silver nanoparticles (Ag-NPs) via an eco-friendly, completely green method. The synthesis involves the use of silver nitrate, gelatin, dextrose and water as the silver precursor, stabilizing agent, reducing agent and solvent respectively. By varying the reaction time, the temporal evolution of the growth, optical, antimicrobial and sensing properties of the as-synthesised Ag-NPs were investigated. The nanoparticles were characterized using UV-vis absorption spectroscopy, Fourier transform infra-red spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HR-TEM). The absorption maxima of the as-synthesized materials at different reaction time showed characteristic silver surface plasmon resonance (SPR) peak. The as-synthesised Ag-NPs show better antibacterial efficacy than the antibiotics; ciproflaxin and imipenem against Pseudomonas aeruginosa with minimum inhibition concentration (MIC) of 6μg/mL, and better efficacy than imipenem against Escherichia coli with MIC of 10μg/mL. The minimum bactericidal concentration (MBC) of the as-synthesised Ag-NPs is 12.5μg/mL. The sensitivity of the dextrose reduced gelatin-capped Ag-NPs towards hydrogen peroxide indicated that the sensor has a very good sensitivity and a linear response over wide concentration range of 10(-1)-10(-6)M H2O2.
    Carbohydrate polymers. 06/2014; 106:469-74.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A rapid synthesis of silver nanoparticles (AgNPs) using Agrimoniae herba extract as reducing agent and stabilizer (A. herba-conjugated AgNPs [AH-AgNPs]) were designed, characterized, and evaluated for antitumor therapy feasibility. In this study, critical factors in the preparation of silver nanoparticles, including extraction time, reaction temperature, the concentration of AgNO3, and A. herba extract amount, were investigated using ultraviolet-visible spectroscopy. AH-AgNPs with well-defined spherical shape, homogeneous distributional small size (30.34 nm), narrow polydispersity index (0.142), and high negative zeta potential (-36.8 mV) were observed by transmission electron microscopy and dynamic light scattering. Furthermore, the results of X-ray diffraction and Fourier-transform infrared spectroscopy further indicated successful preparation of AH-AgNPs. Acceptable long-term storage stability of AH-AgNPs was also confirmed. More importantly, AH-AgNPs displayed significantly higher antiproliferative effect against a human lung carcinoma cell line (A549 cells) compared with A. herba extract and bare AgNPs prepared by sodium citrate. The half-maximal inhibitory concentrations of AH-AgNPs, bare AgNPs, and A. herba extract were 38.13 μg · mL(-1), 184.87 μg · mL(-1), and 1.147 × 10(4) μg · mL(-1), respectively. It is suggested that AH-AgNPs exhibit a strong antineoplastic effect on A549 cells, pointing to feasibility of antitumor treatment in the future.
    International Journal of Nanomedicine 01/2014; 9:1871-1882. · 4.20 Impact Factor

Full-text (4 Sources)

Available from
May 21, 2014