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)₆]^3–/4– redox couple, when two different active electron transfer regions were clearly characterized. Using square-wave voltammetry and a 0.2 mol L⁻¹ phosphate buffer (pH 7.0) as supporting electrolyte, a separation of ca. 180 mV 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 0.12 μmol L⁻¹ and 0.016 μmol L⁻¹, 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.

本文提出了同时测定重要抗生素（阿莫西林– AMX）和抗炎药（尼美舒利–NIM）的首个电分析方法，该方法广泛使用。在这种方法中，用固定在磷酸二十六烷基酯（DHP）膜中的炭黑（CB）改性的玻璃碳（GC）基底用作电化学传感器（CB–DHP / GC）。当清楚地表征了两个不同的活性电子转移区域时，使用[Fe（CN）₆ ] ^{3– / 4–}氧化还原对，通过电化学阻抗光谱法对该传感器的电化学活性进行了评估（与GC相比）。使用方波伏安法和0.2 mol L ^-1磷酸盐缓冲液（pH 7.0）作为支持电解质，分离出约。新型CB-DHP / GC传感器在AMX和NIM的氧化峰电位之间达到180 mV，并且对AMX和NIM的检测限分别为0.12μmolL ^-1和0.016μmolL ^-1。这种新的电分析方法已成功地用于同时测定生物尿液和环境样品中的AMX和NIM。本文提出的方法具有极大的分析价值，因为它比文献中报道的同时测定这些药物的唯一其他方法（基于HPLC）更快捷，更便宜。