TY - JOUR
T1 - Field deployable method for gold detection using gold pre-concentration on functionalized surfaces
AU - Zuber, Agnieszka
AU - Bachhuka, Akash
AU - Tassios, Steven
AU - Tiddy, Caroline
AU - Vasilev, Krasimir
AU - Ebendorff-Heidepriem, Heike
PY - 2020/1/2
Y1 - 2020/1/2
N2 - Gold in a rock is usually associated with other elements, forms nuggets, or is hosted within the crystal lattice of a mineral (e.g., pyrite) and is often heterogeneously distributed and trapped inside the rock matrix even after crushing. Gold can be liberated from these rock matrices by chemical leaching, but then their concentration becomes too low for detection by a portable method due to the dilution effect of the leaching process. In this paper, we present a proof-of-concept method for gold pre-concentration to enable the detection of gold in rock at low levels using a portable technique. Two coating methods, plasma polymerization (PP) and wet chemistry (WC), were utilized to generate surface coatings, which were then compared for their effectiveness in binding gold ions. Laser-induced breakdown spectroscopy (LIBS) was used as a portable technique for the detection of immobilized gold on these modified surfaces. The detection limit for pure gold ions in solution incubated on PP and WC coatings was determined to be as low as 80 ppb. To demonstrate the real-life capability of the method, it was tested for rock sample leachates bearing 300–500 ppb gold.
AB - Gold in a rock is usually associated with other elements, forms nuggets, or is hosted within the crystal lattice of a mineral (e.g., pyrite) and is often heterogeneously distributed and trapped inside the rock matrix even after crushing. Gold can be liberated from these rock matrices by chemical leaching, but then their concentration becomes too low for detection by a portable method due to the dilution effect of the leaching process. In this paper, we present a proof-of-concept method for gold pre-concentration to enable the detection of gold in rock at low levels using a portable technique. Two coating methods, plasma polymerization (PP) and wet chemistry (WC), were utilized to generate surface coatings, which were then compared for their effectiveness in binding gold ions. Laser-induced breakdown spectroscopy (LIBS) was used as a portable technique for the detection of immobilized gold on these modified surfaces. The detection limit for pure gold ions in solution incubated on PP and WC coatings was determined to be as low as 80 ppb. To demonstrate the real-life capability of the method, it was tested for rock sample leachates bearing 300–500 ppb gold.
KW - Gold sensing
KW - Plasma polymerization
KW - Salinization
KW - Surface chemistry
UR - http://www.scopus.com/inward/record.url?scp=85078022060&partnerID=8YFLogxK
UR - http://purl.org/au-research/grants/ARC/CE140100003
U2 - 10.3390/s20020492
DO - 10.3390/s20020492
M3 - Article
C2 - 31952298
AN - SCOPUS:85078022060
SN - 1424-8220
VL - 20
JO - Sensors (Switzerland)
JF - Sensors (Switzerland)
IS - 2
M1 - 492
ER -