Sains Malaysiana 45(8)(2016): 1221–1225

Formation of ZnO Nanorods via Low Temperature Hydrothermal Method for Enzymatic Glucose Sensor

(Pembentukan Batang Nano ZnO melalui Kaedah Hidroterma Suhu Rendah untuk Sensor Enzim Glukosa)

NUR SYAFINAZ RIDHUAN¹, KHAIRUNISAK ABDUL RAZAK¹* & ZAINOVIA LOCKMAN^1,2

¹School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia,

14300 Nibong Tebal, Pulau Pinang, Malaysia

²NanoBiotechnology Research & Innovation (NanoBRI), INFORMM, Universiti Sains Malaysia

11800 USM, Penang, Malaysia

Diserahkan: 20 April 2015/Diterima: 16 November 2015

ABSTRACT

In this study, zinc oxide (ZnO) nanorod arrays were synthesized using a simple hydrothermal reaction on a ZnO seeds/ITO substrate and applied for the fabrication of enzymatic glucose sensor. ZnO nanorod matrix provided a favourable environment for the immobilization of glucose oxidase (GOx) and introduced a shuttling way for electronic communication between GOx and electrode. The performance of different aspect ratio of ZnO nanorods that was produced by varying hydrothermal reaction time was studied. The aspect ratio of ZnO influenced the GOx enzyme immobilization. The morphology and structure of prepared ZnO nanorods were characterized by employing scanning electron microscopy (SEM), and X-ray powder diffraction (XRD). Electrochemical measurements of the sensor showed a reproducible sensitivity of 2.06 μA/cm2mM for ZnO matrix grown for 4 h with the aspect ratio of 8.0.

Keywords: Cyclic-voltammetry; glucose oxidase (GOx); hydrothermal; ZnO nanorods

ABSTRAK

Dalam kajian ini, zink oksida (ZnO) batang nano telah disintesis menggunakan reaksi mudah hidroterma pada benih ZnO/substrat ITO substrat dan digunakan untuk fabrikasi sensor glukosa enzim. ZnO matriks batang nano menyediakan persekitaran yang menggalakkan bagi imobilisasi glukosa oksidase (GOx) seterusya bagi menyediakan laluan komunikasi elektronik antara GOx dan elektrod. Prestasi bagi nisbah aspek batang nano ZnO yang berbeza yang dihasilkan dengan mengubah masa tindak balas hidroterma telah dikaji. Nisbah aspek ZnO mempengaruhi immobilisasi GOx enzim. Morfologi dan struktur ZnO batang nano telah dicirikan dengan menggunakan mikroskop imbasan elektron (SEM) dan pembelauan sinar-X (XRD). Ukuran sensor elektrokimia menghasilkan kesensitifan sebanyak 2.06 µA/cm2mM untuk matrik ZnO yang dihasilkan dengan tindak balas hidroterma selama 4 jam dengan nisbah aspek 8.0.

Kata kunci: Batang nano ZnO; glukosa oksidase (GOx); hidroterma; kitar-voltan

RUJUKAN

Ahmad, R., Tripathy, N., Kim, J.H. & Hahn, Y.B. 2012. Highly selective wide linear-range detecting glucose biosensors based on aspect-ratio controlled ZnO nanorods directly grown on electrodes. Sens. Actuators B 174: 195-201.

Anusha, J.R., Kim, H.J., Fleming, A.T., Das, S.J., Yu, K.H., Kim, B.C. & Raj, C.J. 2014. Simple fabrication of ZnO/Pt/chitosan electrode for enzymatic glucose biosensor. Sens. Actuators B 202: 827-833.

Besbes, S., Ouada, H.B., Davenas, J., Ponsonnet, L., Jaffrezic, N. & Alcouffe, P. 2006. Effect of surface treatment and functionalization on the ITO properties for OLEDs. Mater. Sci. Eng. C 26(2-3): 505-510.

Chen, L., Gu, B., Zhu, G., Wu, Y., Liu, S. & Xu, C. 2008. Electron transfer properties and electrocatalytic behavior of tyrosinase on ZnO nanorod. J. Electroanal. Chem. 617(1): 7-13.

Foo, K.L., Kashif, M., Hashim, U. & Ali, M.E. 2013. Fabrication and characterization of ZnO thin films by sol-gel spin coating method for the determination of phosphate buffer saline concentration. Curr. Nanosci. 9(2): 288-292.

Hwa, K-Y. & Subramani, B. 2014. Synthesis of zinc oxide nanoparticles on graphene-carbon nanotube hybrid for glucose biosensor applications. Biosens. Bioelectron. 62(0): 127-133.

Khusaimi, Z., Amizam, S., Mamat, M.H., Sahdan, M.Z., Ahmad, M.K., Abdullah, N. & Rusop, M. 2010. Controlled growth of zinc oxide nanorods by aqueous-solution method. Synth. React. Inorg. Me. 40(3): 190-194.

Kim, J.Y., Jo, S.Y., Sun, G.J., Katoch, A., Choi, S.W. & Kim, S.S. 2014. Tailoring the surface area of ZnO nanorods for improved performance in glucose sensors. Sens. Actuators B 192: 216-220.

Kong, T., Chen, Y., Ye, Y., Zhang, K., Wang, Z. & Wang, X. 2009. An amperometric glucose biosensor based on the immobilization of glucose oxidase on the ZnO nanotubes. Sens. Actuators B 138(1): 344-350.

Lei, Y., Yan, X., Zhao, J., Liu, X., Song, Y., Luo, N., & Zhang, Y. 2011. Improved glucose electrochemical biosensor by appropriate immobilization of nano-ZnO. Colloids Surf. B 82(1): 168-172.

Lockman, Z., Pet Fong, Y., Wai Kian, T., Ibrahim, K. & Razak, K.A. 2010. Formation of self-aligned ZnO nanorods in aqueous solution. J. Alloys Compd. 493(1-2): 699-706.

Pradhan, D., Niroui, F. & Leung, K.T. 2010. High-performance, flexible enzymatic glucose biosensor based on ZnO nanowires supported on a gold-coated polyester substrate. ACS Appl. Mater. Interfaces 2(8): 2409-2412.

Ridhuan, N.S., Abdul Razak, K., Lockman, Z. & Abdul Aziz, A. 2012. Structural and morphology of ZnO nanorods synthesized using ZnO seeded growth hydrothermal method and its properties as UV sensing. PLoS ONE 7(11).

Tan, W.K., Khairunisak Abdul Razak, Lockman, Z., Kawamura, G., Muto, H. & Matsuda, A. 2014. Synthesis of ZnO nanorod-nanosheet composite via facile hydrothermal method and their photocatalytic activities under visible-light irradiation. J. Solid State Chem. 211: 146-153.

Wohlfahrt, G., Trivić, S., Zeremski, J., Peričin, D. & Leskovac, V. 2004. The chemical mechanism of action of glucose oxidase from Aspergillus niger. Mol. Cell. Biochem. 260(1): 69-83.

Xia, L., Song, J., Xu, R., Liu, D., Dong, B., Xu, L. & Song, H. 2014. Zinc oxide inverse opal electrodes modified by glucose oxidase for electrochemical and photoelectrochemical biosensor. Biosens. Bioelectron. 59: 350-357.

*Pengarang untuk surat-menyurat; email: khairunisak@usm.my