Kachoosangi Roohollah Torabi, Wildgoose Gregory G, Compton Richard G
University of Oxford, Physical and Theoretical Chemistry Laboratory, South Parks Road, Oxford, OX1 3QZ, UK.
Anal Chim Acta. 2008 Jun 16;618(1):54-60. doi: 10.1016/j.aca.2008.04.053. Epub 2008 May 2.
A sensitive electroanalytical methodology for the determination of paracetamol using adsorptive stripping voltammetry (AdsSV) at a multiwalled carbon nanotube modified basal plane pyrolytic graphite electrode (MWCNT-BPPGE) is presented. Both cyclic voltammetric and square wave adsorptive stripping voltammetric techniques are compared. The adsorption occurs at open circuit potential with a 1 min accumulation time. The effect of scan rate and pH were investigated and an optimal scan rate of 100 mVs(-1) and a pH 7.5, 0.05 M phosphate buffer solution (PBS) was used. Additions of paracetamol using cyclic voltammetry exhibits a linear detection range over a wide range of paracetamol concentrations (0.1-25 microM) with a detection limit of 45 nM (based on 3sigma). Additions of paracetamol using square wave adsorptive stripping voltammetry show two linear ranges for paracetamol detection. The first linear range is from 0.01 microM to 2 microM and the second linear range is from 2 microM to 20 microM. Using the first range of this calibration plot, a detection limit of 10nM is obtained for paracetamol. To the best of our knowledge, this limit of detection is the lowest limit of detection has been reported for paracetamol using electrochemical techniques. The method was then successfully utilised for the determination of paracetamol in a real sample of "ANADIN EXTRA" tablets and a recovery of 95% was obtained without interference from aspirin or caffeine. The proposed electroanalytical method using MWCNT-BPPGE is the most sensitive method for determination of paracetamol with lowest limit of detection to date. It has also advantages such as easy handling, resistance against surface fouling, and low cost.
本文介绍了一种灵敏的电分析方法，用于在多壁碳纳米管修饰的基面热解石墨电极（MWCNT-BPPGE）上采用吸附溶出伏安法（AdsSV）测定扑热息痛。比较了循环伏安法和方波吸附溶出伏安法两种技术。吸附在开路电位下进行，积累时间为1分钟。研究了扫描速率和pH值的影响，使用的最佳扫描速率为100 mV s(-1)，pH值为7.5的0.05 M磷酸盐缓冲溶液（PBS）。采用循环伏安法添加扑热息痛，在较宽的扑热息痛浓度范围（0.1 - 25 μM）内呈现线性检测范围，检测限为45 nM（基于3σ）。采用方波吸附溶出伏安法添加扑热息痛，显示出扑热息痛检测的两个线性范围。第一个线性范围是从0.01 μM到2 μM，第二个线性范围是从2 μM到20 μM。使用该校准曲线的第一个范围，扑热息痛的检测限为10 nM。据我们所知，该检测限是使用电化学技术报道的扑热息痛的最低检测限。该方法随后成功用于测定“ANADIN EXTRA”片剂实际样品中的扑热息痛，回收率为95%，且不受阿司匹林或咖啡因的干扰。所提出的使用MWCNT-BPPGE的电分析方法是迄今为止测定扑热息痛最灵敏的方法，检测限最低。它还具有易于操作、抗表面污染和成本低等优点。
