Currently silver nanoparticle (AgNP) is the most widely used NP. Potential hazard of AgNP to the environment, however, is largely unknown. Lack of NP characterization data in most of (eco) toxicology study, transformation of NPs in the test media and environment, etc. have challenged the attempt of presenting NP dose and toxic outcome. Therefore more control over NP ecotoxicology study need to be done. This study was aimed to synthesis a stable, fully characterized and tightly constrained PVP-capped AgNPs via bottom-up method. Modification of Mulfinger et al. (2007) synthesis protocol has been successful in generating spherical and monodisperse PVP-capped AgNPs. Another straightforward synthesis method was developed via ligand-exchanged (indirect method) from a monodisperse citrate-capped AgNPs. PEG-SH, Fulvic acid and Tween-80 polymers was also tried to recap citrate-coated AgNPs. There were no size and shape alterations as PVP and fuvic acid replaced citrate coating, while PEG-SH and Tween-80 polymer did. Ali polymers, nevertheless improved the AgNPs stability in ecotoxicology media. The stability of citrate; PEG-SH; and PVP-capped AgNPs due to incubation in several ecotoxicology media with variation in media ionic strength/concentration and composition was examined. It was seen that PVP polymer showed a better stabilization effect than citrate and PEG-SH. Shape transformation was seen for AgNPs after incubated in media without chloride (nitrate and sulphate media), especially in concentrated media. Thus type of capping agent; media ionic strength and chemical composition determined the behavior and stability of AgNPs in ecotoxicology media.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:619408 |
| Date | January 2014 |
| Creators | Tejamaya, Mila |
| Publisher | University of Birmingham |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://etheses.bham.ac.uk//id/eprint/5360/ |
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