Rodrigues Dayvison Ribeiro, Olivieri Alejandro César, Fragoso Wallace Duarte, Lemos Sherlan Guimarães
Grupo de Estudos Avançados em Química Analítica, Departamento de Química, Universidade Federal da Paraíba, 58051-970, João Pessoa, PB, Brazil.
Departamento de Química Analítica, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Instituto de Química de Rosario (IQUIR-CONICET), Suipacha 531, Rosario, S2002LRK, Argentina.
Anal Chim Acta. 2019 Nov 8;1080:1-11. doi: 10.1016/j.aca.2019.07.047. Epub 2019 Jul 29.
This work investigated the application of partial least-squares regression of complex numbers on multivariate data obtained by electrochemical impedance spectroscopy (EIS). The use of complex numbers-PLS was evaluated in the individual determination of two well-known redox probes: ferrocyanide and hydroquinone. The predictive ability of complex numbers-PLS was evaluated for EIS spectra obtained at different applied potentials and perturbation amplitudes, and was also compared to that obtained with PLS applied to EIS data presented as real numbers - only the real or imaginary part of the complex impedance, or the absolute impedance or the phase angle. It is shown that complex numbers-PLS is more efficient (better prediction models) when more complex electrochemical systems (hydroquinone) are probed. Excellent predictions were obtained for the determination of hydroquinone and catechol in the direct analysis of spiked tap water samples with EIS and complex numbers-PLS.
本研究探讨了复数偏最小二乘回归在电化学阻抗谱（EIS）获取的多变量数据中的应用。在两种著名的氧化还原探针（亚铁氰化物和对苯二酚）的单独测定中评估了复数偏最小二乘回归的使用。针对在不同施加电位和扰动幅度下获得的EIS光谱，评估了复数偏最小二乘回归的预测能力，并将其与应用于仅作为实数呈现的EIS数据的偏最小二乘回归（仅复阻抗的实部或虚部、绝对阻抗或相角）的预测能力进行了比较。结果表明，当探测更复杂的电化学系统（对苯二酚）时，复数偏最小二乘回归更有效（预测模型更好）。在用EIS和复数偏最小二乘回归直接分析加标自来水样品时，对苯二酚和邻苯二酚的测定获得了出色的预测结果。
