Gold digital versatile disc platform modified with nano-porous mercury/gold amalgam as a solid-state disposable electrochemical sensor for detection of para-nitrophenol

Herein, a novel solid-state disposable electrochemical sensor based on gold digital versatile disc (GDVD) platform modified with nano-porous mercury/gold (Hg/Au) amalgam has been constructed for detection of para-nitrophenol (PNP). The modification of GDVD mini-chip was accomplished via a two-step procedure. First, the gold nanoparticles were electrodeposited onto the GDVD surface. Then, an electro-amalgamation step was performed. The formation of nano-porous Hg/Au amalgam was characterized using scanning electron microscopy. Linear sweep voltammetry and square wave voltammetry were used to study the electrochemical behavior of PNP. The influence of several relevant operating parameters was investigated and optimized. The calibration curve was linear within the concentration range of 5 μM to 250 μM of PNP. The detection limit was achieved to be 1 μM (based 3sb/m criterion). Also, the RSDs were found to be 5% for 4 parallel detections with the separate similar electrodes and 3% for 10 successive measurements with one electrode. The proposed sensor was successfully applied for the direct determination of PNP in water samples.