Facultad de Química e Ingeniería Química, Universidad Nacional Mayor de San Marcos, Lima 15081, Peru.
Sensors (Basel). 2024 Aug 22;24(16):5420. doi: 10.3390/s24165420.
This paper presents a new application of a lanthanum oxide (III)-modified carbon paste electrode (La/CPE) for dopamine (DP) detection in the presence of ascorbic acid (AA). The presence of cetyl trimethyl ammonium bromide (CTAB) facilitated the La/CPE electrode's ability to detect DP amidst AA interference, resulting in a substantial 70.0% increase in the anodic peak current for DP when compared to the unmodified carbon paste electrode (CPE). CTAB enabled clear separation of the anodic peaks for DP and AA by nearly 0.2 V, despite their initially overlapping potential values, through the ion-dipole interaction of AA and CTAB. The electrode was characterized using cyclic voltammetry (CV) and energy-dispersive spectroscopy (EDS). The method demonstrated a detection limit of 0.06 µmol/L with a relative standard deviation (RSD) of 6.0% ( = 15). Accuracy was assessed through the relative error and recovery percent, using urine samples spiked with known quantities of DP.
本文提出了一种氧化镧（III）修饰碳糊电极（La/CPE）在抗坏血酸（AA）存在下检测多巴胺（DP）的新应用。十六烷基三甲基溴化铵（CTAB）的存在促进了 La/CPE 电极在 AA 干扰下检测 DP 的能力，与未修饰的碳糊电极（CPE）相比，DP 的阳极峰电流增加了 70.0%。尽管 DP 和 AA 的初始重叠电位值相近，但通过 AA 和 CTAB 的离子偶极相互作用，CTAB 使 DP 和 AA 的阳极峰得以清晰分离，相差近 0.2 V。该电极采用循环伏安法（CV）和能量色散光谱法（EDS）进行了表征。该方法的检测限为 0.06 µmol/L，相对标准偏差（RSD）为 6.0%（n = 15）。通过相对误差和回收率评估了准确性，使用含有已知 DP 量的尿液样本进行测定。
