Synthesis and surface characterization of a chemically modified carbon paste electrode and its application in determination of Hg(II) ion in water, food and dental amalgam samples

Abstract

The development of an easy and affordable method for its determination in various samples is of major interest because the globe is affected by the toxicity of the environment caused by the presence of heavy metals, particularly mercuric ions. For the potentiometric measurement of Hg(II) ions in various materials, an unique carbon paste electrode was created using 1,3-Bis[2-(N-morpholino)acetamidothiophenoxy]propane (BMATPP) as a modifier. With a reaction time of six seconds, the electrode had a Nernstian slope of 30.01 ± 0.52 mV decade-1 over the concentration range of 5 × 10-9-1 × 10-3 mol/L (SD of 5 replicates). It was discovered that the pH range for use was 2.2 to 4.5 and that it was thermally stable up to 60 °C. The selectivity of the suggested sensor towards the Hg(II) ion was investigated using the separate solution method (SSM) and fixed interference technique (FIM), and it demonstrated a satisfactory selectivity. The interaction between the target Hg(II) ions and modifier was demonstrated by scanning electron microscopy (SEM) in conjunction with energy dispersive X-ray (EDX) and infrared (IR). The modifier's contact angle value demonstrated its lipophilicity, which is consistent with its stability and long life. With excellent F-test and t-test values obtained, the Hg(II) ion modified sensor was successfully used for potentiometric analysis of several real samples.