SIPS 2018

DETAILLED PROGRAM OVERVIEW

The Development of Dendrimer-gold Nanocomposite Electrochemical Sensor for the Detection of Lead (II) ion in Water
Kgaogelo Jalda¹; Nonhlangabezo Mabuba²; Omotayo Arotiba²;
¹UNIVERSITY OF JOHANNESBURG, Polokwane, South Africa; ²UNIVERSITY OF JOHANNESBURG, Johannesburg, South Africa;
PAPER: 355/Electrochemistry/Regular (Oral)
SCHEDULED: 16:45/Tue./Copacabana B (150/1st)

ABSTRACT:
In South Africa, industrial development and mining sustains the country's economy. Unfortunately, the effluents from these industries introduce heavy metal pollutants such as lead into the environmental water. Lead(II) is widely recognized as a highly toxic and non-biodegradable metal [1,2,3]. This study addresses a method of monitoring lead(II) by modifying glassy carbon electrode (GCE) with gold nanoparticles (AuNPs) and generation 2 (G2) poly(propyleneimine) dendrimer (PPI), to provide a highly sensitive electrochemical sensor for the determination of lead(II) ions in water using square wave anodic stripping voltammetry (SWASV). The co-deposition of PPI and AuNPs on the surface of GCE was confirmed by field emission scanning microscopy (FESEM). Voltammetric probing showed that the GCE/PPI-AuNP platform exhibited reversible electrochemistry and conductivity in [Fe(CN)6]3-/4- redox probe. The electroactive surface area of the modified electrodes were also calculated in order to illustrate that the prepared PPI+AuNP nanocomposite could improve the surface area and conductivity of the GCE and was found to be 8.17 mm2, GCE-AuNP, 10.84 mm2, GCE-PPI, 11.03 mm2, while 11.13 mm2 was found for GCE-PPI+AuNP. The electroactive surface area of GCE-PPI+AuNP modified electrode increased to approximately 36.23% as compared to bare GCE, which provided an effective evidence for the superior conductivity of PPI+AuNP as expected. The effect of different electrochemical parameters on the sensitivity of the sensor for the Pb2+ detection were also scrutinized, including supporting electrolyte (HNO3), pH (1), deposition potential (-0.8 V) and deposition time (150s). The sensor was applied in the detection of lead(II) in real water sample and it was exhibited good stability and the results were validated by ICPOES.

References:
[1] [1] Pizent, A., Tariba, B. and Živković, T., 2012. Reproductive toxicity of metals in men. Archives of Industrial Hygiene and Toxicology, 63(Supplement 1), pp.35-46.
[2] Aragay, G., Pons, J. and Merkoçi, A., 2011. Recent trends in macro-, micro-, and nanomaterial-based tools and strategies for heavy-metal detection. Chemical reviews, 111(5), pp.3433-3458.
[3] Navas-Acien, A., Guallar, E., Silbergeld, E.K. and Rothenberg, S.J., 2007. Lead exposure and cardiovascular disease: a systematic review. Environmental health perspectives, 115(3), p.472.