▎ 摘　　要

NOVELTY - Preparation of electrochemical dopamine aptamer sensor involves bonding gold-silver bond-modified DNA single strand (dopamine aptamer) to gold nanoparticles of reduced graphene oxide/gold nanoparticle composite prepared by placing graphene oxide-nile blue-modified glassy carbon electrode in a phosphate electrolyte including 1 g/l chloroauric acid, forming gold nanoparticles on surface of glassy carbon electrode, and reducing, adding cyclohexanol, and forming coiled aptamer-dopamine complex on surface of the glassy carbon electrode. USE - Preparation of electrochemical dopamine aptamer sensor used for detection of molar concentration of dopamine in bio fluid sample. ADVANTAGE - The method enables simple and economical preparation of electrochemical dopamine aptamer sensor having excellent sensitivity. The sensor enables efficient detection of molar concentration of dopamine in bio fluid sample. DETAILED DESCRIPTION - Preparation of electrochemical dopamine aptamer sensor involves bonding gold-silver bond-modified DNA single strand (dopamine aptamer) to gold nanoparticles of reduced graphene oxide/gold nanoparticle composite prepared by placing graphene oxide-nile blue-modified glassy carbon electrode in a phosphate electrolyte including 1 g/l chloroauric acid, forming gold nanoparticles on surface of glassy carbon electrode, and reducing, adding cyclohexanol, and forming coiled aptamer-dopamine complex on surface of the glassy carbon electrode. The graphene oxide-nile blue-modified glassy carbon electrode is prepared by dispersing graphene oxide in distilled water, adding 1 g/L nile blue, mixing, and applying resultant mixed solution on surface of glassy carbon electrode. The graphene oxide is prepared by adding 1 g graphite to a three-neck bottle, adding 25 ml concentrated sulfuric acid with concentration of 98%, stirring for 24 hours, adding 1.5 g potassium permanganate, cooling in ice bath, stirring for 30 minutes, heating to 60 degrees C, reacting for 45 minutes, adding 3 ml distilled water, cooling to room temperature, filtering, washing with distilled water, and drying. When the concentration of dopamine increased, the current peak intensity of dopamine is increased, and current peak intensity of nile blue is decreased.