抗坏血酸和尿酸在甘氨酸-壳聚糖修饰玻碳电极上的电化学行为及测定

制备了甘氨酸-壳聚糖复合膜修饰玻碳电极(Gly-CTS/GCE),研究了抗坏血酸(AA)和尿酸(UA)在该修饰电极上的电化学行为。结果表明在pH=5.59的磷酸盐缓冲溶液中,AA、UA在Gly-CTS/GCE上均产生灵敏的不可逆氧化峰,其峰电流与浓度在一定范围内呈良好的线性关系。对AA和UA混合溶液平行测定7次,相对标准偏差分别为4.6%、2.9%,表明该电极重现性和稳定性良好。AA、UA在Gly-CTS/GCE电极上的氧化峰峰电位相差340mV,据此可实现对二者的同时检测,并可应用于实际样品测定。

Electrochemical Behavior and Determination of Ascorbic Acid and Uric Acid on Gly-CTS/GCE Modified Electrode

Chitosan (CTS) and glycine (Gly) were used to prepare glycine/chitosan composite film modified electrode (Gly-CTS/GCE).The electrochemicai behavior of ascorbic acid(AA) and uric acid (UA) was studied.In phosphate buffer solution (PBS,pH =5.59),AA and UA exhibited sensitive irreversible oxidation peak at the Gly-CTS/GCE modified electrode.The oxidation peak currents and their concentration showed a good linear relationship within a certain range.The RSD for 7 times determination of mixture was 4.6 ％,2.9 ％.The sensor shows good stability and reproduction quality.This modified electrode exhibited a well-separated oxidation peaks toward UA and AA with a potential difference of 340 mV,which is large enough to detemine UA and AA individually and simultaneously.The proposed method may be applied to practical samples.