纳米色敏传感-可见/近红外光谱的霉变小麦菌落数定量分析  

Quantitative Determination of the Number of Moldy Wheat Colonies Based on the Nanoscaled Colorimetric Sensor-Visible/Near Infrared Spectroscopy Technology

作　　者：康文翠 林颢[1] 左敏 王卓 段雅娴 陈全胜[1] 林金金 KANG Wen-cui;LIN Hao;ZUO Min;WANG Zhuo;DUAN Ya-xian;CHEN Quan-sheng;LIN Jin-jin(School of Food and Biological Engineering,Jiangsu University,Zhenjiang 212013,China)

机构地区：[1]江苏大学食品与生物工程学院,江苏镇江212013

出　　处：《光谱学与光谱分析》2020年第5期1569-1574,共6页Spectroscopy and Spectral Analysis

基　　金：国家重点研发项目(2016YF0401205-3);2017年度江苏省研究生培养创新工程项目(SJCX17-0581)资助。

摘　　要：提出了以纳米色敏传感器捕获挥发气体为中间介质的可见/近红外光谱检测霉菌感染小麦的新方法。以霉菌感染的小麦为研究对象,在恒温恒湿条件下储藏不同的时间;通过纳米化处理过的色敏传感作为中间介质捕获小麦霉变后产生的特征挥发气体,采用可见/近红外光谱检测分析挥发气体与纳米色敏传感结合前后的可见和近红外区域光谱变化特征,结合多变量分析模型预测小麦的霉菌菌落数。以灰绿曲霉和白曲霉为目标菌种,分别接种至无菌小麦以培养出不同带菌量的小麦样本,分别储藏3~9 d。根据前期的预实验,采用对特征霉变挥发气体敏感的色敏材料(8-(4-硝基苯基)-4,4-二氟硼二吡咯甲烷(NO2BDP)和8-(4-硝基苯基)-4,4-二氟-6-溴硼二吡咯甲烷(NO2BrBDP))组成的纳米传感器捕获特征挥发气体。采用无皂乳化法合成纳米级微球聚苯乙烯-丙烯酸处理色敏材料,提高色敏传感器捕获特征挥发气体的能力,以纳米化前后的NO2BDP和NO2BrBDP四种色敏材料构建传感器阵列。采集不同带菌量的小麦样本的可见/近红外光谱,运用多变量分析方法对光谱信息进行变量筛选,用平板菌落计数法测定菌落总数分别建立灰绿曲霉和白曲霉菌落总数的定量预测模型。实验结果表明,以纳米化NO2BDP和NO2BrBDP组成的传感器阵列为中介采集的带菌小麦的特征光谱波段建立的联合区间-无信息变量消除法偏最小二乘模型(Si-UVE-PLS)效果最佳,此时预测集的交叉验证平方根(RMSECV)为0.4444 lgcfu,实测值与预测值的相关系数Rp为0.9811。采用2个纳米化和2个非纳米材料组成的色敏传感阵列结合联合区间-遗传算法偏最小二乘模型(Si-GA-PLS)检测白曲霉菌落总数取得最佳检测结果,RMSECV为0.4349 lgcfu,Rp为0.9772。表明通过可见/近红外光谱与纳米色敏传感器技术结合的方法,能够良好的完成对挥发性气体的定量检测研究,实现This paper innovatively proposes a new method for detecting mold-infected wheat by visible/near-infrared spectroscopy,and it was employed with a nanoscale colorimetric sensor as an intermediate medium to detect volatile organic compounds(VOCs).The mold-infected wheatwas stored under constant temperature and humidity conditions for different time duration to prepare experimental samples.The wheat after mold infection had different characteristic volatile gases,and visible/near-infrared spectroscopy was used to collect the spectrum information before and after the combination of volatile gas and nanosized colorimetric sensor respectively.The multi-variable analysis model was combined to predict the number of mold colonies of wheat.The Aspergillus glaucus and Aspergillus candidus were inoculated into sterile wheat to cultivate,and wheat samples were prepared by storing for 0~9 days.According to the pre-experimental study,colorimetric material 8-(4-nitrophenyl)-4,4-difluorobora-dipyrromemethane(NO2BDP)and 8-(4-nitrophenyl)-4,4-difluoro-6-bromoborodipyrrolethane(NO2BrBDP)sensitive to volatile gases of wheat was used.A nanosized sensor array was fabricated to detect these characteristic volatile gases.The experiment used the soap-free emulsification method to synthesize a nanoscaled microsphere polystyrene-acrylic acid,and it was used to couple NO2BDP and NO2BrBDP dyes for producing nanoscale colorimetric sensors with high specific sensitivity.The spectral information of each wheat sample with different mold amount was collected by visible/near-infrared technology,as well as pre-processed by multivariate analysis.The number of colonies were determined by plate colony counting method,and quantitative prediction models were respectively established for the total number of Aspergillus glaucus and Aspergillus candidus colonies.The experimental results showed that the Si-UVE-PLS model for predicting the total number of Aspergillus glaucus colonies is the best in the characteristic spectral collected by two nanosized sensor.

关 键 词：可见/近红外光谱 纳米化色敏传感器 多变量分析 小麦 菌落总数 

分 类 号：O434.3[机械工程—光学工程]