A reusable Gemini surfactant-based electrochemical sensor for As(III) detection

ABSTRACT

KSA is one of the rising Gulf regions with many industrial developments, including petrochemicals, mining, agriculture, and pharmaceuticals. These activities have a direct impact on the climate and water resources. A Gemini surfactant has been used for enabling the electrochemical detection of As(III) at the indium tin oxide (ITO) electrode. Monitoring of As(III) in the presence of Gemini surfactant compared either in the presence of cetyltrimethylammonium bromide (CTAB) surfactant or in the absence of any surfactant was studied. The results showed that the cyclic voltammetry (CV) response of 70 ppb of As(III) at bare ITO in the absence of any surfactant shows a background response. In contrast, 1 mM of CTAB showed a weak oxidation peak at 630 mV without any cathodic peak. On the other hand, the capability of monitoring As(III) species in the presence of Gemini surfactant in neutral pH showed high sensitivity with a low limit of detection of 0.88 ppb. The calibration plot was fit using a linear, exponential Langmuir model. Thus, the bare ITO electrode itself could not detect the As(III); while, the use of the Gemini surfactant enhances the electrochemical activity of ITO towards the As(III). The efficiency of this Gemini surfactant is higher than that of CTAB. The presented sensor showed high reversibility that could conduct without a decrease in the sensor activity. Furthermore, this sensor’s selectivity was verified based on the detection of As(III) in the existence of a high concentration of various organic and inorganic interferences.

KEYWORDS:

• Gemini surfactant
• reusable sensor
• As (III)
• cyclic voltammetry
• copper (II)
• square wave voltammetry

Acknowledgments

The authors extend their appreciation to the Deputyship for Research & Innovation, Ministry of Education in Saudi Arabia for funding this research work through the project number (MoE-IF-20-02/08).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Ministry of Education in Saudi Arabia [MoE-IF-20-02/08].