聚磺基水杨酸/碳纳米管修饰电极在抗坏血酸共存时测定多巴胺

Determination of dopamine in the presence of ascorbic acid using poly(sulfosalicylic acid)/multi-wall carbon nanotube film modified electrode

研究了聚磺基水杨酸／多壁碳纳米管修饰玻碳电极的制备及多巴胺在此修饰电极上的电化学行为，讨论了修饰条件、扫速、溶液pH以及抗坏血酸的干扰对多巴胺在这种复合物电极上响应的影响。在pH7.4磷酸盐缓冲溶液中，在1.0×10^-3mol／L抗坏血酸共存的条件下，多巴胺氧化峰电流与其浓度在5×10^-7—10^-4mol／L范围内分段呈线性关系，检出限为1.0×10^-7mol／L。结果表明：聚磺基水杨酸／多壁碳纳米管修饰电极结合了多壁碳纳米管灵敏度高和聚磺基水杨酸选择性好的优点，可用于抗坏血酸共存条件下多巴胺的测定。

Modification of a glassy carbon electrode by poly（sulfosalicylic acid）/multi-wall carbon nanotube （PSA/ MWCNT） film and its application for determination of dopamine （DA） in the presence of ascorbic acid （AA） are investigated. The effects of modification conditions, scan rate, pH value and interference on the response of the composite modified electrode toward DA were discussed. In phosphate-buffered saline solutions （PBS） of pH 7.4, the oxidation current increased linearly with two concentration intervals of DA in the range of 5.0×10^-7 to 1.0× 10^-4mol/L with a detection limit of 1.0×10^-7 mol/L. This approach takes advantage of the excellent sensitivity and selectivity of PSA and MWCNT, which makes the PSA/MWNT modified electrode relatively potential for selective and sensitive determination of DA in the presence of AA.