29th July 2009

Poly-phenothiazine derivative-modified glassy carbon electrode for NADH electrocatalytic oxidation

Delia Gligor, Yusuf Dilgin, Ionel Catalin Popescu and Lo Gorton

• The amperometric detection of NADH, at +200 mV vs. SCE, is described by the following electroanalytical parameters: a sensitivity of 1.82 mA M⁻¹, a detection limit of 2 μM and a linear domain up to 0.1 mM NADH.
• Bis-phenothiazin-3-yl methane (BPhM):

• The GC electrode was mechanically polished with alumina (Al₂O₃, 1 μm) to a mirror finish and then cleaned by sonication in Millipore water
• The peak potential separation (ΔE_p 67 mV, at 20 mV s⁻¹) and the high value of the peak width at half peak height (100 mV) in comparison with their theoretical values (0 and 45.3 mV, respectively) confirm the quasi-reversible character of the surface-confined redox process, generating the voltammetric response of the GC/poly-BPhM modified electrode. REF 35 = R.W. Murray In: W.H. Saunders Jr., Editor, Techniques of Chemistry vol. 22, Wiley, New York (1992)