Figure 1.

(A) Comparison of voltammetric curves obtained during determination of 30 µM Kyn using the bare GCE (a-b) and the Nafion film modified GCE (c-d) in 0.1 M H₂SO₄ (scan rate 0.02 V/s). In (b) and (d) Kyn was accumulated onto the electrode surface at potential of +0.75 V for 60 seconds from the stirring solution. (B) DPAdSVs obtained at the Nafion covered (a) BDDE and (b) GCE after Kyn accumulation.