The modification of glassy carbon electrode (GCE) with nano-gold(NG) by che
mical adsorption of 2-aminoethane thoil (AET) was achieved for the first ti
me. On this electrode 15-mer ss-DNA was immobilized, then ss-DNA/NG/AET/GCE
was formed. By using Co(bpy)(3)(3+), hybridization events of the immobiliz
ed ss-DNA was well detected. It was found that the NG could possibly cause
a parr of the ss-DNA to denature and bind Co(bpy)(3)(3+). However soaking i
n pH 7.0 phosphate buffer solution, denaturization can be avoided and recog
nition ability of hybridization was enhanced. Cyclic voltammetric behavior
of Co(bpy)(3)(3+/2+) bound to the ds-DNA/NG/AET/GCE was studied. It was fou
nd that the peak current(i(p)) showed a linear dependence on the potential
scan rate up to 80 mV/s. It was demonstrated that GCE modified with NG by t
his method had higher stability and reliability.