title: Electrochemical sensor for guanine using a self-assembled monolayer of 1,8,15,22-tetraaminophthalocyanatonickel(II) on glassy carbon electrode.
abstract: This article describes the selective determination of guanine (G) using the self-assembled monolayer (SAM) of 1,8,15,22-tetraaminophthalocyanatonickel(II) (4α-Ni(II)TAPc) modified glassy carbon electrode (GCE) in 0.2 M acetate buffer solution (pH 4.0). The SAM of 4α-Ni(II)TAPc was formed on GCE by spontaneous adsorption of 1 mM 4α-Ni(II)TAPc in dimethylformamide (DMF). It shows two pairs of redox waves corresponding to Ni(III)/Ni(II) and Ni(III)Pc(-1)/Ni(III)Pc(-2) in 0.2 M acetate buffer solution. The SAM modified electrode exhibits excellent electrocatalytic activity toward the oxidation of G by enhancing its oxidation current with 150 mV less positive potential shift in contrast to bare GCE. Furthermore, the SAM modified electrode selectively determines G in the presence of high concentration of adenine (A). In differential pulse voltammetry measurements, the oxidation current response of G was increased linearly in the concentration range of 10 to 100 μM, and a detection limit was found to be 3×10(-8)M (signal/noise=3).
authors.affiliation: Department of Chemistry, Gandhigram Rural Institute, Gandhigram, Dindigul 624 302, India.
authors.forename: A John
authors.initials: AJ
authors.lastname: Jeevagan
authors.forename: S Abraham
authors.initials: SA
authors.lastname: John
mesh_terms: D000225:Adenine / Q000032:analysis; D015374:Biosensing Techniques / Q000295:instrumentation*; D002244:Carbon / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000295:instrumentation* / Q000379:methods*; D004566:Electrodes; D005898:Glass / Q000737:chemistry*; D006147:Guanine / Q000032:analysis*; D007700:Kinetics; D009532:Nickel / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D015203:Reproducibility of Results
chemical_list: C574657:1,8,15,22-tetraaminophthalocyanatonickel(II); D009942:Organometallic Compounds; D006147:Guanine; D002244:Carbon; D009532:Nickel; D000225:Adenine