Document Type : Research Article

Authors

• Huda Abdullah ^{1, 2}
• Norshafadzila Mohammad Naim ³
• Mohamad Aiman Arif Awang Omar ⁴
• Jian Xian Kang ⁵
• Iskandar Yahya ^{6, 2}
• Noorfazila Kamal ^{6, 2}
• Norazreen Abd Aziz ^{6, 2}
• Atiqah Mohd Afdzaluddin ^{2, 7}
• Noraziah Mohammad Zin ⁸
• Mohd Hafiz Dzarfan Othman ⁹
• Wing Fen Yap ¹⁰

¹ Department of Electrical, Electronic and System Engineering, Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

² Advanced Semiconductor Materials and Devices, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Malaysia

³ Department of Electrical, Electronic and System Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia

⁴ Department of Electrical, Electronic and System Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia.

⁵ Department of Electrical and Electronic and System Engineering, Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia.

⁶ Department of Electrical and Electronic and System Engineering, Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia.

⁷ Institute of Microengineering and Nanoelectric, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

⁸ Centre for Diagnostic, Therapeutic and Investigative Studies, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

⁹ Advanced Membrane Technology Research Centre, School of Chemical and Energy Engineering, Universiti Teknologi Malaysia, Johor Bahru, Johor, Malaysia.

¹⁰ Department of Physics, Faculty of Science, Universiti Putra Malaysia, Serdang, Selangor, Malaysia

Abstract

Carbon nanotubes (CNTs) are particularly attractive for use in sensors for environmental and health monitoring. This study proposes a new approach in developing polymer-metal-based sensor for E. coli detection by using CNTs incorporation. PANI-SnO₂ nanocomposite thin films were combined with CNTs to be fabricated as biosensing devices. PANI-(SnO₂)_1-x-CNT_x nanocomposite thin films were synthesized using sol-gel method and deposited on a glass substrate by spin coating technique. The prepared thin films were characterized by X-ray diffraction (XRD), field scanning electron microscopy (FESEM), atomic field microscopy (AFM) and ultraviolet-visible (UV-vis) spectroscopy. The sensitivity performance of PANI-(SnO₂)_1-x-CNT_x nanocomposite thin films were conducted by using current-voltage (I-V) measurements. From the results, XRD patterns show the appearance of PANI, SnO₂ and C peaks and the increasing crystallite size with the increasing of CNT concentration. FESEM images show the spherical shape of SnO₂ and the nanotubes of carbon in the diameter size range 30 – 100 nm and 150 – 220 nm respectively. AFM analysis has found out the roughness parameter has increased when CNT percentage was increased. The peaks from UV-Vis absorbance bands indicated the presence of CNT and SnO₂ at wavelength 270 nm and 370 nm respectively. From I-V measurement of the sensor, PANI-(SnO₂)_1-x-CNT_x with x = 0.03 performed the highest sensitivity which is 16.32%. The results demonstrate that the increasing of CNT concentrations was increasing the sensitivity of PANI-(SnO₂)_1-x-CNT_x thin films towards E. coli.

Graphical Abstract

Keywords

• Polyaniline
• SnO2
• CNT
• E. coli
• sensor

Main Subjects

• Nanomaterials & Nanotechnology