Department of Chemistry, Federal University of São Carlos, C.P. 676, 13560-970 São Carlos, SP, Brazil.
Department of Chemistry, Federal University of São Carlos, C.P. 676, 13560-970 São Carlos, SP, Brazil.
Talanta. 2018 Mar 1;179:115-123. doi: 10.1016/j.talanta.2017.10.048. Epub 2017 Oct 24.
The first electroanalytical method for the simultaneous determination of an important antibiotic (amoxicillin - AMX) and an anti-inflammatory drug (nimesulide -NIM), widely used in combination, is here proposed. In this method, a glassy carbon (GC) substrate modified with carbon black (CB) immobilized within a dihexadecylphosphate (DHP) film is used as electrochemical sensor (CB-DHP/GC). The electrochemical activity of this sensor was assessed (comparatively to that of GC) by electrochemical impedance spectroscopy, using the [Fe(CN)] redox couple, when two different active electron transfer regions were clearly characterized. Using square-wave voltammetry and a 0.2molL phosphate buffer (pH 7.0) as supporting electrolyte, a separation of ca. 180mV between the oxidation peak potentials of AMX and NIM was obtained with the novel CB-DHP/GC sensor, and the obtained detection limits for AMX and NIM were 0.12μmolL and 0.016μmolL, respectively. This new electroanalytical method was successfully applied in the simultaneous determination of AMX and NIM in biological urine and environmental samples. The here-proposed method is of great analytical interest, as it is faster and cheaper than the only other method (based on HPLC) reported in the literature for the simultaneous determination of these drugs.
本文提出了一种同时测定两种广泛联合使用的重要抗生素（阿莫西林- AMX）和抗炎药（尼美舒利- NIM）的电化学分析方法。在该方法中，玻碳（GC）基底用固定在双十六烷基磷酸酯（DHP）膜内的炭黑（CB）修饰，用作电化学传感器（CB-DHP/GC）。通过电化学阻抗谱，使用[Fe（CN）]氧化还原对，评估了该传感器的电化学活性，当两个不同的活性电子转移区域被清楚地表征时。使用方波伏安法和 0.2molL 的磷酸盐缓冲液（pH 7.0）作为支持电解质，在新型 CB-DHP/GC 传感器上获得了 AMX 和 NIM 的氧化峰电位之间约 180mV 的分离，并且获得的 AMX 和 NIM 的检测限分别为 0.12μmolL 和 0.016μmolL。该新的电分析方法成功地应用于生物尿液和环境样品中 AMX 和 NIM 的同时测定。所提出的方法具有很大的分析意义，因为它比文献中报道的唯一另一种（基于 HPLC）同时测定这些药物的方法更快、更便宜。
