A molecularly imprinted sol-gel (MISG)/Au@Ag core-shell NU sensor is proposed for organic vapor detection in an optical fiber-based reflection mode. The compact structure design of the system in the reflection model is promising for practical use as a portable and rapid responsivity sensing probe. Volatile organic acids (OAs) are analogs to biogenetic volatile organic vapors related to specific human diseases. Here, Au@Ag core-shell nano-urchins exhibiting branched tips were synthesized and deposited on indium tin oxide (ITO) glass in small dimer and trimmer clusters to generate an enhanced electric field. A MISG solution was then spin-coated on the substrate to fabricate MISG-LSPR sensors, and three types of MISGs were developed for the detection of hexanoic acid, heptanoic acid and octanoic acid. The normalized spectral response indicated selectivity of the MISG-LSPR sensors for the corresponding template OAs. With Native Bayes and linear discriminant analysis of the sensor responses, where the latter were detected by the proposed system, single- and mixed-OA vapors could be classified into separate clusters. This signified that the proposed MISG-LSPR sensor can be applied toward pattern recognition of single vapors or multiple vapor mixtures.

提出了一种分子印迹溶胶-凝胶（MISG）/ Au @ Ag核壳型NU传感器，用于基于光纤的反射模式下的有机蒸气检测。反射模型中系统的紧凑结构设计有望作为便携式和快速响应感测探针实际应用。挥发性有机酸（OAs）是与特定人类疾病相关的生物遗传性挥发性有机蒸气的类似物。在此，合成了具有支化尖端的Au @ Ag核-壳型纳米胆，并以小的二聚体和三聚体簇的形式沉积在氧化铟锡（ITO）玻璃上，以产生增强的电场。然后将MISG溶液旋涂在基板上以制造MISG-LSPR传感器，并开发出三种类型的MISG用于检测己酸，庚酸和辛酸。归一化的光谱响应指示MISG-LSPR传感器对相应模板OA的选择性。通过本机贝叶斯（Native Bayes）和对传感器响应的线性判别分析（通过建议的系统检测到后者），可以将单OA和混合OA蒸气分类为单独的簇。这表明所提出的MISG-LSPR传感器可用于单蒸气或多蒸气混合物的模式识别。