{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,15]],"date-time":"2026-03-15T01:48:15Z","timestamp":1773539295048,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2011,4,1]],"date-time":"2011-04-01T00:00:00Z","timestamp":1301616000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A Nafion-Graphene (Nafion-G) nanocomposite solution in combination with an in situ plated mercury film electrode was used as a highly sensitive electrochemical platform for the determination of Zn2+, Cd2+, Pb2+ and Cu2+ in 0.1 M acetate buffer (pH 4.6) by square-wave anodic stripping voltammetry (SWASV). Various operational parameters such as deposition potential, deposition time and electrode rotation speed were optimized. The Nafion-G nanocomposite sensing platform exhibited improved sensitivity for metal ion detection, in addition to well defined, reproducible and sharp stripping signals. The linear calibration curves ranged from 1 \u00b5g L\u22121 to 7 \u00b5g L\u22121 for individual analysis. The detection limits (3\u03c3 blank\/slope) obtained were 0.07 \u00b5g L\u22121 for Pb2+, Zn2+ and Cu2+ and 0.08 \u00b5g L\u22121 for Cd2+ at a deposition time of 120 s. For practical applications recovery studies was done by spiking test samples with known concentrations and comparing the results with inductively coupled plasma mass spectrometry (ICP-MS) analyses. This was followed by real sample analysis.<\/jats:p>","DOI":"10.3390\/s110403970","type":"journal-article","created":{"date-parts":[[2011,4,4]],"date-time":"2011-04-04T10:07:21Z","timestamp":1301911641000},"page":"3970-3987","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":131,"title":["Metallo-Graphene Nanocomposite Electrocatalytic Platform for the Determination of Toxic Metal Ions"],"prefix":"10.3390","volume":"11","author":[{"given":"Chandre M.","family":"Willemse","sequence":"first","affiliation":[{"name":"Sensor Lab, Department of Chemistry, University of the Western Cape, Bellville 7535, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Khotso","family":"Tlhomelang","sequence":"additional","affiliation":[{"name":"Sensor Lab, Department of Chemistry, University of the Western Cape, Bellville 7535, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nazeem","family":"Jahed","sequence":"additional","affiliation":[{"name":"Sensor Lab, Department of Chemistry, University of the Western Cape, Bellville 7535, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Priscilla G.","family":"Baker","sequence":"additional","affiliation":[{"name":"Sensor Lab, Department of Chemistry, University of the Western Cape, Bellville 7535, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6102-0433","authenticated-orcid":false,"given":"Emmanuel I.","family":"Iwuoha","sequence":"additional","affiliation":[{"name":"Sensor Lab, Department of Chemistry, University of the Western Cape, Bellville 7535, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2011,4,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6534","DOI":"10.1021\/ic0493696","article-title":"Addressing lead toxicity: Complexation of lead (II) with thiopyrone and hydroxypyridinethione O, S mixed chelators","volume":"43","author":"Lewis","year":"2009","journal-title":"Inorg. 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