Electrochemical Investigation of a Tm(III)–5,10,15,20-Tetrakis(4-isopropylphenyl)porphyrin Complex Modified Glassy Carbon Electrode and its Interaction with Bovine Serum Albumin

Abstract

The electrochemical behavior of a glassy carbon (GC) electrode modified with a thin Tm(III)–5,10,15,20-tetrakis(4-isopropylphenyl)porphyrin complex ([Tm(iPPP)(μ-OH)(H²O)]²) film was investigated. Two pairs of voltammetric current peaks P ¹ and P ² located at about +0.75 and +1.00 V were observed in the potential range 0.00 to +1.20 V. It was found that anions greatly affect the electrochemical characteristics of the [Tm(iPPP)(μ-OH)(H²O)]² film on the GC electrode. A near Nernstian response of was observed. Furthermore, the interaction of the [Tm(iPPP)(μ-OH)(H²O)]² film with bovine serum albumin (BSA) was studied. The shape of the voltammetric current peaks changed greatly after soaking the modified electrode in BSA solution for 50 min. An irreversible reduction peak was appeared at +0.367 V, P ² disappeared and I ^p1 decreased with the concentration of BSA increased. This result was also verified by fluorescence spectrophotometry. Analysis of the modified electrode's surface morphology confirmed that BSA has indeed interacted with the complex modified on the electrode.

Keywords:

• Thulium–porphyrin complex
• Bovine serum albumin
• Modified electrode
• Voltammetry