Integrated gold-disk microelectrode modified with iron(II)-phthalocyanine for nitric oxide detection in macrophages

An integrated gold-disk microelectrode (IGME) was fabricated and modified with Fe(II)-phthalocyanine (Fe(II)-PC) for NO detection in biological media. Microanalysis of NO using square wave anodic stripping voltammetry (SWASV) in 0.01 M HClO₄ was optimal at the initial potential of 0.1 V, frequency of 100 Hz, pulse amplitude of 25 mV, and a scan rate of 200 mV/s. When the electrode was modified with Fe(II)-phthalocyanines, the anodic peak current and sensitivity of NO were remarkably increased due to the catalytic oxidation of NO. The calibration curve had good linearity in the range from 3.6×10⁻⁵ to 7.2×10⁻⁷ M, and the detection limit was (5.7±1.2)×10⁻⁷ M. Fe(II)-phthalocyanine modified gold-disk microelectrode coated with Nafion was applied to determination of NO released from macrophage cell.