Mostafa Gamal Abdel Hafiz, Hefnawy Mohamed, Al-Majed Abdulrahman
King Saud University, College of Pharmacy, Pharmaceutical Chemistry Department, PO Box 2457, Riyadh 11451, Saudi Arabia.
J AOAC Int. 2010 Mar-Apr;93(2):549-55.
The construction and electrochemical response characteristics of polyvinylchloride (PVC) membrane sensors for donepezil HCl (DP) are described. The sensing membranes incorporated ion-association complexes of DP cation and sodium tetraphenyl borate (sensor 1), phosphomolybdic acid (sensor 2), or phosphotungstic acid (sensor 3) as electroactive materials. The sensors displayed a fast, stable, and near-Nernstian response over a relatively wide DP concentration range (1 x 10(-2) to 1 x 10(-6) M), with cationic slopes of 53.0, 54.0, and 51.0 mV/ concentration decade over a pH range of 4.0 to 8.0. The sensors showed good discrimination of DP from several inorganic and organic compounds. The direct determination of 2.5-4000.0 microg/mL DP showed average recoveries of 99.0, 99.5, and 98.5%, and mean RSDs of 1.6, 1.5, and 1.7% at 100.0 microg/mL for sensors 1, 2, and 3, respectively. The proposed sensors have been applied for direct determination of DP in two pharmaceutical preparations. The results obtained for determination of DP in tablets using the proposed sensors compared favorably with those obtained using an HPLC method. The sensors have been used as indicator electrodes for potentiometric titration of DP.
描述了用于盐酸多奈哌齐（DP）的聚氯乙烯（PVC）膜传感器的构建及其电化学响应特性。传感膜包含DP阳离子与四苯硼酸钠（传感器1）、磷钼酸（传感器2）或磷钨酸（传感器3）的离子缔合物作为电活性材料。这些传感器在相对较宽的DP浓度范围（1×10⁻²至1×10⁻⁶ M）内呈现出快速、稳定且接近能斯特响应，在pH值4.0至8.0范围内，阳离子斜率分别为53.0、54.0和51.0 mV/浓度 decade。这些传感器对DP与几种无机和有机化合物具有良好的区分能力。对2.5 - 4000.0 μg/mL DP的直接测定显示，传感器1、2和3在100.0 μg/mL时的平均回收率分别为99.0%、99.5%和98.5%，平均相对标准偏差分别为1.6%、1.5%和1.7%。所提出的传感器已应用于两种药物制剂中DP的直接测定。使用所提出的传感器测定片剂中DP的结果与使用高效液相色谱法获得的结果相比具有优势。这些传感器已用作DP电位滴定的指示电极。
