Feng Meng-Qun, Yildirim Tanju, Minami Kosuke, Shiba Kota, Yoshikawa Genki
Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba, Japan.
Materials Science and Engineering, Graduate School of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki, Japan.
Sci Technol Adv Mater. 2024 Sep 24;25(1):2408212. doi: 10.1080/14686996.2024.2408212. eCollection 2024.
For olfactory sensors, clear differentiation of complex odour samples requires diverse information. To obtain such information, hardware modifications, such as introducing additional channels with different physical/chemical properties, are usually needed. In this study, we present a new approach to augmenting the sensing signals of an olfactory sensor by modulating the flow rate of the carrier gas. The headspace vapour of complex odours is measured using a sensing system of nanomechanical sensor (Membrane-type Surface stress Sensor, MSS). The resulting data set is quantitatively evaluated using the Davies-Bouldin index (DBI) of principal component analysis (PCA). The increasing number of sensing signals obtained at different gas flow rates leads to a decrease in the DBI, achieving better cluster separation between different odours. Such gas flow effects can be attributed to several factors, including the sample evaporation and the equilibrium of the gas-liquid and gas-solid interfaces. Proton-transfer-reaction time-of-flight mass spectrometry (PTR-TOF-MS) experiments reveal that the compositions of odour samples vary with the different gas flow rates. It is demonstrated that a simple technique for modulating gas flow rates can significantly improve the differentiation performance of complex odours, providing an additional degree of freedom in olfactory sensing.
对于嗅觉传感器而言，要清晰区分复杂气味样本需要多样的信息。为获取此类信息，通常需要对硬件进行改进，比如引入具有不同物理/化学性质的额外通道。在本研究中，我们提出了一种通过调节载气流量来增强嗅觉传感器传感信号的新方法。使用纳米机械传感器（膜式表面应力传感器，MSS）的传感系统来测量复杂气味的顶空蒸汽。使用主成分分析（PCA）的戴维斯 - 布尔丁指数（DBI）对所得数据集进行定量评估。在不同气体流速下获得的传感信号数量增加会导致DBI降低，从而实现不同气味之间更好的聚类分离。这种气流效应可归因于几个因素，包括样品蒸发以及气 - 液和气 - 固界面的平衡。质子转移反应飞行时间质谱（PTR - TOF - MS）实验表明，气味样本的成分会随不同的气体流速而变化。结果表明，一种调节气体流速的简单技术可以显著提高对复杂气味的区分性能，为嗅觉传感提供了一个额外的自由度。
