Highly sensitive determination of promazine in pharmaceutical and biological samples using a ZnO nanoparticle-modified ionic liquid carbon paste electrode

In this work we describe the first report for the determination of promazine using a nanostructure- modified ionic liquid carbon paste electrode in aqueous solutions. To achieve this goal, a novel modified carbon paste electrode using ZnO nanoparticles and l-methyl-3-butylimidazolium bromide as a binder （ZnO/NPs/ILs/CPE） was fabricated. The oxidation peak potential of promazine at the surface of the ZnO/ NPs/ILs/CPE appeared at 685 mV, which was about 65 mV lower than the oxidation potential at the surface of CPE under similar conditions. Also, the peak current was increased to about 4.0 times higher at the surface of ZnO/NPs/ILs/CPE compared to that of CPE. The linear response range and detection limit were found to be 0.08-450 and 0.04 μmol/L, respectively. The modified electrode was successfully used for the determination of promazine in real samples with satisfactory results.

离子液体-银纳米粒子修饰电极的制备及其在测定维生素C中的应用

分别制备了离子液体[BMIM]BF4和银纳米粒子(AgNPs),并配制1.5 mol·L^(-1)AgNPs溶液,将上述离子液体与AgNPs溶液按4∶96的体积比混合后滴于经抛光的玻碳电极(GCE)上,将此经修饰的电极置于30℃真空干燥5 min,即得[BMIM]BF4-AgNPs/GCE修饰电极。对此修饰电极的电化学特性以及维生素C(Vc)在此电极上的电化学行为作了研究。结果表明:用上述修饰电极作为工作电极,SCE为参比电极,Pt电极为辅助电极,方波伏安法测定Vc时,Vc浓度在5~100μmol·L^(-1)内与相应的峰电流值之间呈线性关系,测定的灵敏度为0.4μA·μmol^(-1)。应用此方法测定了Vc片剂中Vc的含量,测定值与文献值一致,测定值的相对标准偏差(n=5)小于2.0%。

Hb/Fe_3O_4/CILE修饰电极的制备及应用

以类离子液体碳糊电极（CILE）为基体电极，采用滴涂法和利用静电吸附作用，制备了Hb／Fe3O4／CILE修饰电极，研究了Hb的直接电化学及其电催化行为，建立了H20：的计时安培测定新方法。结果表明：Hb在该修饰电极上。Hb呈现了一对准可逆的氧化还原峰，且其在该修饰电极表面表观覆盖度为2．65×10-9moL／cm2；电子转移速率常数为1．35／s；表观米氏常数为1．59×10-5mol／L。在1．0×10-6～4．0×10-5mol／L范围内，催化电流与H202浓度呈线性关系（r=0．9976），检出限为3．0×10-7moL／L（S／N=3）。

银纳米粒子修饰电极的优化及在抗坏血酸测定中的应用

以离子液体[BMIM]BF4及银纳米粒子为原料,按一定比例混合修饰玻碳电极,研制了电化学传感器。借助紫外可见分光光度法、循环伏安法及阻抗等手段对电极性能进行了研究。探讨了银纳米粒子与离子液体的比例对修饰电极的性能的影响,对修饰电极进行了优化。电化学传感器应用于实际样品中的抗坏血酸测定,加标回收率可96.3%,RSD为2.3%。