Fahimi-Kashani Nafiseh, Hormozi-Nezhad M Reza
Department of Chemistry and Institute of Nanoscience and Nanotechnology, Sharif University of Technology, Tehran 11155-9516, Iran.
ACS Omega. 2018 Feb 1;3(2):1386-1394. doi: 10.1021/acsomega.7b01780. eCollection 2018 Feb 28.
Most array-based sensing platforms, to date, utilize static response patterns for discrimination of a wide variety of analytes, but only a few studies have focused on the important task of quantitatively resolving structural isomers, which are nowadays important because of their broad usage in medicines and industries. A possible way of accomplishing this feat is to combine (rather than static) sensor response profiles with the chemical tongue strategy to allow the development of array-based sensors for isomeric discrimination. Here, by adding the time dimension, a simple and novel gold nanorod (AuNR)-based chrono-colorimetric sensor array is proposed for chemical discrimination applications. Because of their similar structure but different redox potentials, dihydroxybenzene (DHB) structural isomers have been chosen, as models, to evaluate the applicability of the proposed array. The principle of the array relies on various growth rates of silver shells on AuNRs at different silver ion/AuNR concentration ratios owing to the different kinetic behaviors of DHBs, which can be used as fingerprints to identify DHBs with the help of multivariate analysis methods. The combinatorial colorimetric response of AuNRs upon DHB addition has been analyzed by linear discriminant analysis and hierarchical cluster analysis. Finally, identification of individual DHBs or their mixtures in real samples confirms the potential application of the proposed array.
迄今为止，大多数基于阵列的传感平台利用静态响应模式来区分各种各样的分析物，但只有少数研究关注定量解析结构异构体这一重要任务，由于结构异构体在医药和工业中的广泛应用，如今这一任务变得很重要。实现这一目标的一种可能方法是将（而非静态的）传感器响应曲线与化学舌策略相结合，以开发用于异构体鉴别的基于阵列的传感器。在此，通过增加时间维度，提出了一种简单新颖的基于金纳米棒（AuNR）的计时比色传感器阵列用于化学鉴别应用。由于二羟基苯（DHB）结构异构体结构相似但氧化还原电位不同，已将其选作模型来评估所提出阵列的适用性。该阵列的原理基于在不同银离子/AuNR浓度比下，由于DHBs的动力学行为不同，AuNRs上银壳的生长速率各异，借助多变量分析方法，这些速率可用作识别DHBs的指纹。通过线性判别分析和层次聚类分析，分析了添加DHB后AuNRs的组合比色响应。最后，对实际样品中单个DHBs或其混合物的识别证实了所提出阵列的潜在应用。
