Abstract:
This study presented a new method to design a MIP-based electrochemical sensor that could improve the selective and sensitive detection of ipratropium bromide (IPR). The polymeric film was designed using 2-hydroxyethyl methacrylate (HEMA) as the basic monomer, 2-hydroxy-2-methylpropiophenone as the initiator, ethylene glycol dimethacrylate (EGDMA) as the crosslinking agent, and N-methacryloyl-L-aspartic acid (MAAsp) as the functional monomer. The presence of MAAsp results in the functional groups in imprinting binding sites, while the presence of poly(vinyl alcohol) (PVA) allows the generation of porous materials not only for sensitive sensing but also for avoiding electron transport limitations. Electrochemical characterizations of the changes at each stage of the MIP preparation process were confirmed using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). In addition, morphological characterizations of the developed sensor were performed using scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and contact angle measurements. Theoretical calculations were also performed to explain/confirm the experimental results better. It was found that the results of the calculations using the DFT approach agreed with the experimental data. The MAAsp-IPR@MIP/GCE sensor was developed using the photopolymerization method, and the sensor surface was obtained by exposure to UV lamp radiation at 365 nm. The improved MIP-based electrochemical sensor demonstrated the ability to measure IPR for standard solutions in the linear operating range of 1.0 × 10-12-1.0 × 10-11 M under optimized conditions. For standard solutions, the limit of detection (LOD) and limit of quantification (LOQ) were obtained as 2.78 × 10-13 and 9.27 × 10-13 M, respectively. The IPR recovery values for the inhalation form were calculated as 101.70 % and 100.34 %, and the mean relative standard deviations (RSD) were less than 0.76 % in both cases. In addition, the proposed modified sensor demonstrated remarkable sensitivity and selectivity for rapid assessment of IPR in inhalation forms. The sensor\'s unique selectivity is demonstrated by its successful performance even in the presence of IPR impurities.
摘要:
本研究提出了一种设计基于MIP的电化学传感器的新方法,该传感器可以提高异丙托溴铵(IPR)的选择性和灵敏度。以甲基丙烯酸2-羟乙酯(HEMA)为基本单体,2-羟基-2-甲基苯丙酮作为引发剂,乙二醇二甲基丙烯酸酯(EGDMA)作为交联剂,和N-甲基丙烯酰基-L-天冬氨酸(MAAsp)作为功能单体。MAAsp的存在导致印迹结合位点中的官能团,而聚乙烯醇(PVA)的存在允许产生多孔材料,不仅用于灵敏的传感,而且还用于避免电子传输限制。使用循环伏安法(CV)和电化学阻抗谱(EIS)确认了MIP制备过程每个阶段变化的电化学表征。此外,使用扫描电子显微镜(SEM)对开发的传感器进行形态学表征,衰减全反射-傅里叶变换红外光谱(ATR-FTIR),和接触角测量。还进行了理论计算以更好地解释/确认实验结果。发现使用DFT方法的计算结果与实验数据一致。使用光聚合方法开发了MAAsp-IPR@MIP/GCE传感器,并且通过暴露于365nm的UV灯辐射获得传感器表面。改进的基于MIP的电化学传感器证明了在优化条件下在1.0×10-12-1.0×10-11M的线性工作范围内测量标准溶液的IPR的能力。对于标准溶液,检测限(LOD)和定量限(LOQ)分别为2.78×10-13和9.27×10-13M,分别。吸入型的IPR回收率分别为101.70%和100.34%,两种情况下的平均相对标准偏差(RSD)均小于0.76%。此外,所提出的改良传感器对快速评估吸入形式的IPR表现出显著的灵敏度和选择性。即使在存在IPR杂质的情况下,其成功的性能也证明了传感器的独特选择性。