Self-Assembled Iron Oxide Nanoparticle-Modified APTES-ITO Electrode for Simultaneous Stripping Analysis of Cd(II) and Pb(II) Ions

Noorhashimah Mohamad Nor; Sarasijah Arivalakan; Nor Dyana Zakaria; Nithiyaa Nilamani; Zainovia Lockman; Khairunisak Abdul Razak

doi:10.1021/acsomega.1c07158

Self-Assembled Iron Oxide Nanoparticle-Modified APTES-ITO Electrode for Simultaneous Stripping Analysis of Cd(II) and Pb(II) Ions

ACS Omega. 2022 Jan 19;7(4):3823-3833. doi: 10.1021/acsomega.1c07158. eCollection 2022 Feb 1.

Authors

Noorhashimah Mohamad Nor¹, Sarasijah Arivalakan¹, Nor Dyana Zakaria², Nithiyaa Nilamani³, Zainovia Lockman¹, Khairunisak Abdul Razak^{1

2}

Affiliations

¹ School of Materials & Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia.
² NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 Penang, Malaysia.
³ Centre for Marine and Coastal Studies, Universiti Sains Malaysia, 11800 Penang, Malaysia.

Abstract

Carboxyl (-COOH)-stabilized iron oxide nanoparticles (IONPs) synthesized through co-precipitation were used to modify an indium tin oxide (ITO) electrode, which was chemically functionalized with 3-aminopropyltriethoxysilane (APTES) for heavy metal detection. The effect of soaking time (30, 60, 90, and 120 min) of IONP-COOH self-assembled on an APTES-ITO electrode was studied. Cyclic voltammetry and scanning electron microscopy were applied to analyze the electrochemical properties and morphologies of IONP-COOH/APTES-ITO modified electrode. The modified electrodes were then employed for the simultaneous detection of Cd(II) and Pb(II) by using square wave anodic stripping voltammetry. At 90 min of soaking time, excellent electrochemical performance and larger effective surface area (A _e) were obtained. The linear range for the simultaneous detection of Cd(II) and Pb(II) ions using the modified electrode was 10-100 ppb with limits of detection of 0.90 and 0.60 ppb, respectively. The interference study revealed a low interference effect from Cr(III), Hg(II), Zn(II), Cu(II), Mg(II), Na(I), and K(I) toward the simultaneous detection of Cd(II) and Pb(II). Finally, the IONP-COOH/APTES-ITO-modified electrode was applied to analyze seawater samples and was able to simultaneously detect Cd(II) and Pb(II) ions.