AbstractA carbon paste electrode (CPE) was modified with graphite oxide (GrO) and β-cyclodextrin (CD) to obtain a sensor for simultaneous voltammetric determination of levodopa (LD), piroxicam (PRX), ofloxacin (OFX) and methocarbamol (MCB). The morphology, structure and electrochemical properties of the functionalized GrO were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, contact angle measurements and cyclic voltammetry. Under the optimal experimental conditions, the sensor is capable of detecting LD, PRX, OFX and MCB by square wave voltammetry (SWV) at working potentials of +0.40, +0.60, +1.03 and + 1.27 V (versus Ag/AgCl), respectively. Response is linear from 1.0 to 20 μM for LD, from 1.0 to 15 μM for PRX, from 1.0 to 20 μM for OFX, and from 1.0 to 50 μM for MCB. The respective limits of detection are 65, 105, 89 and 400 nM. The method was successfully applied to the simultaneous determination of LD, PRX, OFX and MCB in (spiked) real river water and synthetic urine samples, and the results were in agreement with those obtained using a spectrophotometric method, with recoveries close to 100%. Graphical abstractSchematic presentation of a novel electroanalytical method employing a carbon paste electrode modified with graphite oxide and β-cyclodextrin for the simultaneous determination of levodopa, piroxicam, ofloxacin and methocarbamol in urine and river water samples by square wave voltammetry.

中文翻译：

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使用氧化石墨和β-环糊精修饰的碳糊电极同时伏安法检测左旋多巴、吡罗昔康、氧氟沙星和甲氧巴莫

摘要 用氧化石墨 (GrO) 和 β-环糊精 (CD) 修饰碳糊电极 (CPE) 以获得用于同时伏安法测定左旋多巴 (LD)、吡罗昔康 (PRX)、氧氟沙星 (OFX) 和甲氧卡巴莫 (MCB) 的传感器. 通过扫描电子显微镜、能量色散 X 射线光谱、接触角测量和循环伏安法表征了功能化 GrO 的形态、结构和电化学性能。在最佳实验条件下，该传感器能够通过方波伏安法 (SWV) 在 +0.40、+0.60、+1.03 和 +1.27 V（相对于 Ag/AgCl）的工作电位下分别检测 LD、PRX、OFX 和 MCB . 响应在 LD 的 1.0 至 20 μM、PRX 的 1.0 至 15 μM、OFX 的 1.0 至 20 μM 和 MCB 的 1.0 至 50 μM 之间呈线性关系。各自的检测限为65，105、89 和 400 nM。该方法成功应用于同时测定（加标）真实河水和合成尿液样品中的LD、PRX、OFX和MCB，结果与使用分光光度法获得的结果一致，回收率接近100%。图形摘要：采用经氧化石墨和β-环糊精改性的碳糊电极通过方波伏安法同时测定尿液和河水样品中的左旋多巴、吡罗昔康、氧氟沙星和甲氧卡巴莫的新型电分析方法的示意图。回收率接近 100%。图形摘要：采用经氧化石墨和 β-环糊精改性的碳糊电极通过方波伏安法同时测定尿液和河水样品中的左旋多巴、吡罗昔康、氧氟沙星和甲氧卡巴莫的新型电分析方法的示意图。回收率接近 100%。图形摘要：采用经氧化石墨和β-环糊精改性的碳糊电极通过方波伏安法同时测定尿液和河水样品中的左旋多巴、吡罗昔康、氧氟沙星和甲氧卡巴莫的新型电分析方法的示意图。