Self-assembled monolayers (SAMs) of chemisorbed cysteamine on gold electrode surfaces have been used as base interfaces forthe deposition of the Au colloid. Different Au colloids, ranging in particles of diameter 2.6, 16, 42 and 51 nm, can be depositedon self-assembled cysteamine monolayers on a gold electrode. Fe(CN)64 adsorbed on Au colloid surfaces yields a pair ofsymmetric adsorption peaks with half-peak width (W1:2) of 90.2 mV and peak-to-peak separation (DEp) of 3 mV in 1.0 M KNO3solution containing 1.00 10 3 M K3Fe(CN)6. The dependence of peak current on scan rate (n) is linear. DEp of the adsorptionwave increases while the Au colloid size decreases. The apparent specific capacitances of a bare gold electrode, the cysteaminemodifiedelectrode and the Au colloid modified electrode measured by cyclic voltammetry at 500 mV are 57.8, 32.0 and 81.1 mFcm 2, respectively.