Metallophthalocyanine-nanofibre-based electrodes for electrochemical sensing of biomolecules

Metal phthalocyanines, possessing rich redox chemistry due to the presence of the central metal cation and pyrrolic nitrogen atoms of the macrocycle, are explored as electrochemical sensors. Nickel phthalocyanine nanofibres (NiPc NF) prepared by a simple chemical route are coated on a pencil graphite rod and the electrocatalytic performance of NiPc NF electrode is investigated for quantitative detection of ascorbic acid (AA) in 0.2 M phosphate buffer solution. The performance of NiPc NFs is shown to be superior to that of commercial NiPc and is attributed to the high electrochemically active surface area available for fibres. The electrode exhibits linearity for the detection over a wide concentration range of AA from (5.5,upmu hbox {M}) to 5.2 mM. The detection limit for AA sensing with NiPc-NF-modified electrode is (1.5,upmu hbox {M}). The higher performance of NiPc fibres due to its nanostructure morphology may be utilized for the quantitative detection of other biomolecules.