Heavy Metals in Philippine Rice (Oryza Sativa) using Nafion- [Ru(bpy)3]2+-Gold Nanoparticles Modified Glassy Carbon Electrodes

  • S. Palisoc Condensed Matter Physics Laboratory, De La Salle University, 2401 Taft Avenue, Manila 0922, Philippines
  • C. Canquin Condensed Matter Physics Laboratory, De La Salle University, 2401 Taft Avenue, Manila 0922, Philippines
  • M. Natividad Condensed Matter Physics Laboratory, De La Salle University, 2401 Taft Avenue, Manila 0922, Philippines

Abstract

Nafion-Ru(bpy)32+-Gold Nanoparticles (AuNPs) modified glassy carbon electrodes were fabricated and were used in detecting heavy metals in Philippine rice samples by differential pulse voltammetry (DPV). The said electrodes were fabricated via the drop coating technique. The concentrations of the modifiers, Ru(bpy)32+ and AuNPs, were varied to determine the best electrode for detecting lead, cadmium, and copper. Based on DPV results, the electrode with 5 mg Ru(bpy)32+ and 3 mg AuNPs was chosen as the best electrode. The calibration curves of the best electrode showed strong correlation values of 0.9984 for lead, 0.9905 for cadmium, and 0.9933 for copper. The limit of detection for lead, cadmium, and copper were 10 mg/L, 10 mg/L, and 200 mg/L, respectively. Atomic absorption spectrometry was used as a cross reference to verify the results from DPV. The lead and cadmium content of all the rice samples exceeded the World Health Organizaton (WHO) limit that the body can take. Some samples contained copper above the WHO limit.

References

[1] Y. Fan, T. Zhu, M. Li, J. He, R. Huang, J. Healthc. Eng., 2017, 4124302 (2017).
[2] D.E. Keil, J. Berger-Ritchie, G. A. McMillin, Lab. Medicine, 42, 735 (2011).
[3] S. Smirjdkova, O. Ondrasovicova, A. Kaskova, A. Lakticova, Folia Vet., 49, S31 (2005).
[4] K. Dzieżyc, T. Litwin, G. Chabik, A. Członkowska, Gait Pos-ture, 42, 601 (2015).
[5] W. Xu, J. Anal. Sci. Meth. Instrum., 75 (2013).
[6] L. Xiao, H. Xu, S. Zhou, T. Song, W. Huanhuan, Electrochim. Acta, 143, 143 (2014).
[7] J. Barek, Port. Electrochim. Acta, 31, 6 (2013).
[8] H. Kim, S. Yoon, H.N. Choi, Y.K. Lyu, W.Y. Lee, Korean Chem. Soc., 27, 65 (2006).
[9] Y. Ni, P. Wang, H. Song, X. Lin, S. Kokot, Anal. Chim. Acta, 821, 34 (2014).
[10]E. Canbay, E. Akyilmaz, Anal. Biochem., 444, 8 (2014).
[11]L. Yang, G. Wang, Y. Liu, M. Wang, Talanta, 113, 135 (2013).
[12]L. Yang, G. Wang, Y. Liu, Anal. Biochem., 237, 144 (2013).
[13]S. Palisoc, B. Tuason, M. Natividad, Optoelectron. Adv. Mat., 9, 1435 (2015).
[14]Kaw K., Palisoc S. and Natividad M., Philipp. Sci. Let., 7, 171 (2014).
[15]S. Palisoc, M. Natividad, F. Co, K. Kaw, Optoelectron. Adv. Mat., 9, 1010 (2015).
[16]S. Palisoc, M. Natividad, N. Martinez, R. Ramos, K. Kaw, e-Polymers, 16, 117 (2015).
[17]S. Palisoc, M. Natividad, P. DeVera, B. Tuason, Philipp. Sci. Lett., 7, 372 (2014).
[18]S. Palisoc, M. Natividad, P. DeVera, B. Tuason, J. New Mat. Electr. Sys., 17, 205 (2014).
[19]S. Palisoc, M. Natividad, D. Calde, E. Rosopa, J. New Mat. Electr. Sys., 19, 223 (2016).
[20]S. Palisoc, N. Valeza, M. Natividad, Int. J. Electrochem. Sci., 12, 3859 (2017).
[21]S. Palisoc N. Causing, M. Natividad, Anal. Methods, 9, 4217 (2017).
[22]S. Palisoc, K. Kaw, M. Natividad, J. Robles, J. New Mat. Electr. Sys., 20, 77 (2017).
[23]S. Palisoc, D. Uy, M. Natividad, T.B. Lopez, Mater. Res. Ex-press, 4, 116406 (2017).
[24]T. B. Lopez, S. Palisoc, M. Natividad, Sens Biosensing Res., 15, 34 (2017).
[25]A. Fagan-Murphy, M. Allen, B. Patel, Electrochim. Acta, 152, 249 (2015).
Published
2018-08-14
Section
Full Articles