{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,22]],"date-time":"2025-11-22T11:16:32Z","timestamp":1763810192045,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2020,1,15]],"date-time":"2020-01-15T00:00:00Z","timestamp":1579046400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000923","name":"Australian Research Council","doi-asserted-by":"publisher","award":["CE140100003"],"award-info":[{"award-number":["CE140100003"]}],"id":[{"id":"10.13039\/501100000923","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>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\u2013500 ppb gold.<\/jats:p>","DOI":"10.3390\/s20020492","type":"journal-article","created":{"date-parts":[[2020,1,17]],"date-time":"2020-01-17T04:14:41Z","timestamp":1579234481000},"page":"492","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Field Deployable Method for Gold Detection Using Gold Pre-Concentration on Functionalized Surfaces"],"prefix":"10.3390","volume":"20","author":[{"given":"Agnieszka","family":"Zuber","sequence":"first","affiliation":[{"name":"Institute for Photonics and Advanced Sensing, School of Physical Sciences, The University of Adelaide, Adelaide 5005, Australia"},{"name":"Deep Exploration Technologies Cooperative Research Centre, School of Physical Sciences, The University of Adelaide, Adelaide 5005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1253-8126","authenticated-orcid":false,"given":"Akash","family":"Bachhuka","sequence":"additional","affiliation":[{"name":"Institute for Photonics and Advanced Sensing, School of Physical Sciences, The University of Adelaide, Adelaide 5005, Australia"},{"name":"Deep Exploration Technologies Cooperative Research Centre, School of Physical Sciences, The University of Adelaide, Adelaide 5005, Australia"},{"name":"ARC Center of Excellence for Nanoscale BioPhotonics, The University of Adelaide, Adelaide 5005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Steven","family":"Tassios","sequence":"additional","affiliation":[{"name":"Deep Exploration Technologies Cooperative Research Centre, School of Physical Sciences, The University of Adelaide, Adelaide 5005, Australia"},{"name":"CSIRO, Process Science and Engineering, Gate 1, Normanby Road, Clayton 3169, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Caroline","family":"Tiddy","sequence":"additional","affiliation":[{"name":"Deep Exploration Technologies Cooperative Research Centre, School of Physical Sciences, The University of Adelaide, Adelaide 5005, Australia"},{"name":"Future Industries Institute, University of South Australia, Mawson Lakes 5095, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Krasimir","family":"Vasilev","sequence":"additional","affiliation":[{"name":"Future Industries Institute, University of South Australia, Mawson Lakes 5095, Australia"},{"name":"School of Engineering, University of South Australia, Mawson Lakes 5095, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heike","family":"Ebendorff-Heidepriem","sequence":"additional","affiliation":[{"name":"Institute for Photonics and Advanced Sensing, School of Physical Sciences, The University of Adelaide, Adelaide 5005, Australia"},{"name":"Deep Exploration Technologies Cooperative Research Centre, School of Physical Sciences, The University of Adelaide, Adelaide 5005, Australia"},{"name":"ARC Center of Excellence for Nanoscale BioPhotonics, The University of Adelaide, Adelaide 5005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,15]]},"reference":[{"key":"ref_1","first-page":"155","article-title":"Gold analysis-fire assaying and alternative methods","volume":"7","author":"Hoffman","year":"1998","journal-title":"Explor. 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