基于凝胶与纳米碳管复合体化学传感器的研究及人工味觉应用

纳米碳管与高聚物复合体由于其独特的电学、光学、机械等性质,成为目前研究的前沿和热点,并呈现出令人振奋的应用潜力。本文介绍了其导电机理,首次制备了两种基于凝胶高聚物与单壁纳米碳管复合体薄膜的化学传感器,并将其应用于实验室开发的电子舌系统,采用阻抗法测量传感器在不同液体中的频率响应,最后对数据用主成分分析法进行模式识别,初步实验结果表明所制备的传感器能较好的区别酸、甜、苦、咸等味道。     

基于电子舌技术的果汁饮料识别

本研究的电子舌由多个性能彼此重叠的味觉传感器阵列与基于BP算法的神经网络模式识别工具组成,它能够识别出几种不同的果汁饮料.研究表明,电子舌识别的电信号与味觉有关的化学物质成分有相关性,可以实现在线检测或监测.     

基于调幅脉冲扫描法的电子舌及其在酒类识别中的应用

为了能够对酒类进行区分识别,提出了一种基于调幅脉冲扫描方法的电子舌系统.应用由丝网印刷电极、检测电路和调幅扫描脉冲等组成的高性能电子舌对六种不同品牌的干红葡萄酒进行了测量,并通过特征值提取和主成分分析对数据进行了分析处理和识别研究.特征值提取减少了系统的处理数据量,主成分分析表明该电子舌系统能够很好的区分不同品牌的葡萄酒.为研制酒类质量检测仪器和酒类品质评判系统提供了新方法和新构架.     

电子舌常用传感器研究进展

电子舌是一种用于液体分析的多传感器系统,它主要由传感器阵列、信号处理和模式识别系统组成,其中,味觉传感器是决定其性能的关键部件之一。介绍了几种常用味觉传感器的研究和应用现状,重点讨论了电位分析传感器、伏安分析传感器和光学方法的味觉传感器的原理、特点及其应用,同时,对电子舌传感器的发展进行了展望。     

基于电子舌技术的葡萄酒分类识别研究

利用电子舌系统对六种不同的葡萄酒进行检测,通过对传感器响应信号的处理及选取适当的模式识别方法,取得了较好的区分效果.结果表明,电子舌能够区分开不同产地(山东烟台、河北昌藜、河北沙城)的葡萄酒、同时对不同品种(赤霞珠、品丽珠、蛇龙珠)的葡萄酒也做出了较好的分类判别.在模式识别中,判别因子分析法对于产地和葡萄品种的识别结果均优于主成分分析法,前2维主成分的累计贡献量达到了99.9%.     

伏安型电子舌对不同品种中药材的检测

中药在我国卫生体系中占有非常重要的地位,其质量好坏对人们的健康至关重要.提出了应用伏安型电子舌对不同品种的中药材进行分类鉴别研究.采用差分脉冲伏安法和方波伏安法,分别以玻碳电极和金电极作为工作电极来检测被识别样品,并利用主成分分析法对其检测后的数据进行分析.结果显示:同种实验方法下应用双电极体系检测的识别结果要优于单电极体系检测的识别结果,不同实验方法下基于差分脉冲伏安法检测的识别结果要优于基于方波伏安法检测的识别结果.应用伏安型电子舌对中药材进行检测能够很好地区分不同品种的中药材,为伏安型电子舌系统在中药材领域的研究提供了一定的基础.     

基于电子舌技术的辛味中药材鉴别研究

为检验电子舌对辛味中药材种类与质量的鉴别能力,应用传感器矩阵系统ASTREE电子舌分别对不同种类,不同产地以及不同生产批次的辛味中药材进行检测,所得数据用主成分分析法(PCA)进行分析处理。结果表明:该电子舌不仅可以很好地区分6种不同的辛味中药材,而且对于同种类型不同产地,不同生产批次的中药材样本也有很好的辨识能力。由此可见,电子舌在辛味中药材的种类鉴别中有巨大的应用潜力。     

LAPS型电子舌神经网络味觉识别

根据光寻址电位传感器(LAPS)原理,提出一种结合主成分分析和反向传播(BP)神经网络识别溶液味觉的方法。对LAPS电子舌采集的味觉数据主成分进行提取,将该主成分作为BP神经网络的训练样本,通过训练和学习构建味觉数据与味觉类别之间的联系,用训练后的BP网络对溶液进行味觉识别。对浓度分别为20 ppm、100 ppm、300 ppm和500 ppm的酸、甜、苦、咸、鲜5种味觉溶液进行识别验证,准确率达96.6%,结果表明该方法能够在不同浓度下正确识别出溶液的味觉。     

一种声电复合多元液体浓度传感器的研制

在分析目前液体成分浓度测量方法的基础上,提出了一种用于多元液体成分浓度测量的声电联合检测新方法,并重点介绍了传感器的结构和传感器设计中的非线性、温度补偿等几个关键问题.用牛乳这一多元液体作为被测对象对这种测试方法和传感器进行了验证,测试精度与参考方法非常接近.该传感器能同时对多个成分浓度测量,具有测试速度快、精度高、稳定性好、能测试不透明液体、成本低等优点.     

用于环境检测的电子舌研究

介绍我们在用于环境检测中的电子舌方面的研究研制的几种新型的离子传感器,包括基于表面光伏技术的集成离子传感器、光化学原理的集成光学离子传感器阵列,其特点是采用硅微加工技术实现微结构离子器件的研制.介绍了电子舌中采用的信号处理和模式识别技术和我们研制的新型的用于海洋环境检测电子舌仪器.最后给出了电子舌用于环境检测的一些实验结果.     

Combined electronic nose and tongue for a flavour sensing system

We present a novel, smart sensing system developed for the flavour analysis of liquids. The system comprises both a so-called “electronic tongue” based on shear horizontal surface acoustic wave (SH-SAW) sensors analysing the liquid phase and a so-called “electronic nose” based on chemFET sensors analysing the gaseous phase. Flavour is generally understood to be the overall experience from the combination of oral and nasal stimulation and is principally derived from a combination of the human senses of taste (gustation) and smell (olfaction). Thus, by combining two types of microsensors, an artificial flavour sensing system has been developed. Initial tests conducted with different liquid samples, i.e. water, orange juice and milk (of different fat content), resulted in 100% discrimination using principal components analysis; although it was found that there was little contribution from the electronic nose. Therefore further flavour experiments were designed to demonstrate the potential of the combined electronic nose/tongue flavour system. Consequently, experiments were conducted on low vapour pressure taste-biased solutions and high vapour pressure, smell-biased solutions. Only the combined flavour analysis system could achieve 100% discrimination between all the different liquids. We believe that this is the first report of a SAW-based analysis system that determines flavour through the combination of both liquid and headspace analysis.     

电子舌及其应用研究

介绍了电子舌的发展历程和电子舌的研制与应用现状。主要阐述了多通道电极味觉传感器、伏安法电子舌、生物传感器和电子舌敏感膜的研制;电子舌和电子鼻的应用情况。     

Quality control of oral herbal products by an electronic tongue—Case study on sage lozenges

Quality control of complex herbal extracts remains a challenge for analytical procedures as only representative ingredients can be characterized, but not the whole extract. A promising alternative are electronic tongues which are, due to sensors’ non-specificity, able to globally characterize complex mixtures. This article elaborates the application of an electronic tongue as an alternative method in quality control of herbal lozenges as a case study. The Insent taste sensing system SA402B was used equipped with 7 sensors imitating the taste stimuli and sensory signals umami, saltiness, astringency, bitterness and sourness. The results were compared to well-established analytical procedures like high performance liquid chromatography and gas chromatography. Further, a human taste panel (n = 13) was used as reference method.A measurement protocol was developed for quality control and validated according to ICH guideline Q2. The validation showed that all sensors could be used. After measuring different samples, especially the sensors for saltiness and astringency showed adequate results in comparison to the HPLC and GC analysis. Two samples were found to have different taste properties which could be confirmed by low cineol content determined by gas chromatography. In comparison to human taste assessment the electronic tongue was more sensitive to distinguish between specified and outlying taste. Data evaluation based on univariate statistics as well as multivariate could be used to detect the differing samples. Therefore, the Insent taste sensing system seems to be a promising analytical tool for quality control of complex herbal mixtures.     

Hybrid electronic tongue for the characterization and quantification of grape variety in red wines

A multisensor system combined with multivariate analysis was applied to the characterization of red wines and to the quantification of the grape variety percentage. The proposed system, known as hybrid electronic tongue, consists of a colorimetric optofluidic system and an array of electrochemical sensors. Three monovarietal red wines were studied: Pinot Noir, Merlot and Cabernet Sauvignon. Homemade mixtures were elaborated from these wines according to a Simplex experimental design with 60 samples. The data obtained were treated using advanced chemometric tools like Principal Component Analysis (PCA) and Soft Independent Modeling Class Analogy (SIMCA) for the classification of the wine mixtures and Partial Least Squares (PLS) regression for the quantification of the grape variety composition. The results have shown a good classification of the grape varieties and the identification of the mixtures with Pinot Noir up to 75%. Besides, using the PLS regression, the system has demonstrated a high potential for quantifying the percentage of each grape variety.     

Electronic nose technique potential monitoring mandarin maturity

Over the past years, electronic nose technology opened the possibility to exploit information on behavior aroma to assess fruit ripening stage. The objective in this study was to evaluate the capacity of electronic nose to monitoring the change in volatile production of mandarin during different picking-date, using a specific electronic nose device (PEN 2). Principal component analysis (PCA) and linear discriminant analysis (LDA) were used in order to investigate whether the electronic nose was able to distinguish among different picking-date (ripeness states). The loadings analysis was used to identify the sensors responsible for discrimination in the current pattern file. The results obtained prove that the electronic nose PEN 2 can discriminate successfully different picking-date on mandarin using LDA analysis. But, electronic nose was not able to detect a clear difference in volatile profile on mandarin using PCA analysis. During external validation using LDA was obtained to classified 92% of the total samples properly. Some sensors have the highest influence in the current pattern file for electronic nose PEN 2. A subset of few sensors can be chosen to explain all the variance. This result could be used in further studies to optimize the number of sensors.     

基于集成气敏传感器阵列的电子鼻系统环境响应特性分析

基于集成气敏传感器阵列和多传感器信息融合技术的电子鼻系统 ,可用于气体 /气味的定性定量识别 .在实际应用中 ,被识别样本的浓度、样本环境的温度和湿度参数等都对电子鼻系统的响应特性有较大的影响 .本文分别利用纯净空气及乙醇或葡萄酒作为载气及分析样本 ,对电子鼻系统响应特性与气敏传感器工作温度以及样本温度、环境湿度、样本浓度间的依赖关系进行了实验分析 ,并分别给出了它们间依赖关系的实验结果 .