The Analysis of Gold in Plants and Soils by Inductively Coupled Plasma Mass Spectrometry.

Williams, Carl A. (1996) The Analysis of Gold in Plants and Soils by Inductively Coupled Plasma Mass Spectrometry. Doctoral thesis, University of Surrey (United Kingdom)..

Preview

Text 27750450.pdf Available under License Creative Commons Attribution Non-commercial Share Alike. Download (41MB) | Preview

Abstract

Inductively coupled plasma mass spectrometry (ICP-MS) was employed for the determination of gold in plant materials. Optimum conditions for maximum gold (197Au) signal were found to be a nebuliser flow rate of 1.02 l min-1 at a forward power of 1.2 kW. Dissolution of plant materials was achieved by investigating two procedures. Excellent recovery (102±3.6%) and reproducibility were obtained for procedure 2 (i.e. a simple aqua regia-hydrofluoric acid attack). Wash out with an 8% aqua regia solution eliminated gold ‘memory effects’. Internal standardisation was achieved by iridium (193Ir). Quality control assurance for gold analyses was insured by NIST 1571 Orchard Leaves and two ‘in-house’ reference materials. The methodologies developed were applied to three separate studies. Under experimental conditions bryophytes were treated with solutions containing gold and multi-elements. All species exhibited a high degree of gold accumulation, as high as 6.90 μg g-1 (dry wt.)-producing a percentage uptake from solution of 69%. Significant relationships were noted between gold levels and elements reported in the literature to be associated with gold (i.e. Ag, As, Fe). Secondly, a region of known gold mineralisation in Scotland was investigated. Three distinct zones of gold mineralisation were noted, with gold levels of 620 and 302 ng g-1 (dry wt.), in contrast to background levels of 3.9 and 4.2 ng g-1 (dry wt.) in plant and soil materials, respectively. Finally, plant and soil materials were removed from the vicinity of a gold mine in New Zealand. The highest gold levels were observed for bryophytes with a mean gold concentration of 4791 ng g-1 (dry wt.). This work highlights the analytical difficulties in determining gold in plant materials by ICP-MS and demonstrates the efficacious use of bryophytes as a plant medium for the uptake of gold.

Item Type:	Thesis (Doctoral)
Divisions :	Theses
Authors :	Williams, Carl A.
Date :	1996
Additional Information :	Thesis (Ph.D.)--University of Surrey (United Kingdom), 1996.
Depositing User :	EPrints Services
Date Deposited :	14 May 2020 15:43
Last Modified :	14 May 2020 15:48
URI:	http://epubs.surrey.ac.uk/id/eprint/856862

Actions (login required)

View Item

Downloads