Fig. 4

Varying the current during the galvanostatic oxidation step. The overlayer was treated with 0.12 mg/mL of OX1006 in 0.4 M sodium carbonate buffer (pH 10.8), containing 0.23 M NaCl and 0.1 % TX-100. The procedure consisted of a 10 s wait time after application of 7 μL of saliva, followed by galvanostatic oxidation at 300, 800, 1200, 1500 or 3000 nA for 30 s