多巴胺检测新方法的研究

Study on New Detection Method of Dopamine

目的建立在抗坏血酸(AA)和尿酸(UA)同时存在情况下,测定神经递质药物多巴胺(DA)含量的电化学新方法。方法采用循环伏安法研究DA在导电聚合膜修饰玻碳电极上的电化学行为,以差示脉冲伏安(DPV)法建立DA含量测定方法。结果在pH=5.0磷酸盐缓冲液(PBS)中,聚溴百里香酚蓝(BTB)导电聚合物膜对AA,DA,UA有很强电催化作用,明显增强了电极反应的可逆性,同时能实现DA,AA,UA的良好分离。在试验优化条件下,DA氧化峰电流与其浓度在1.0×10-6～1.5×10-4mol/L范围内呈良好的线性关系,检测限为1.0×10-8mol/L。结论建立了在AA和UA同时存在的情况下,DA定量检测的电化学新方法,并将此方法用于实际样品盐酸多巴胺注射液的含量检测,结果令人满意。

Objective To develop a new method for the determination of dopamine （DA） in the condition of coexisting ascorbic acid （AA） and uric acid （UA） by the electrochemical method. Methods The cyclic valtammetric method was adopted to research the electrochemical behavior of DA on poly bromothymol blue （BTB） film modified glassy carbon electrode （GCE）, and the new detected method of DA was developed by differential pulse valtammetry （DPV）. Results In phosphate buffer solution （pH 5.0）, the poly-BTB electropolymerized film had strong electro- catalysis effect on AA, DA and UA, obviously increased the reversibility of electrode reaction, and simultaneously realized the good separation of D, AA and UA. Under the experimental optimized condition, the DA oxidation peak current demonstrated the good linear relationship with the concentration range of 1.0 ×10-6 - 1.5 ×10μ-4mol/L. The detection limit was 1.0×10^8 mol/L. Conclusion The new electrochemical method for quantitatively detecting DA in condition of coexisting AA and UA is established. This method can be applied to determine the content in the actual sample of DA hydroehloride injection with satisfactory results.