基于荧光光谱的液态混合物检测方法及系统研究

发布时间：2018-07-15 12:27

【摘要】：本文对液态混合物检测方法及系统的理论和应用基础进行了研究。将实验测量与量子计算相结合,研究了合成食品色素荧光光谱机理和合成食品色素溶液荧光偏振特性;将荧光光谱技术与多变量统计分析算法相结合,研究了合成食品色素混合溶液中各组分的测定方法以及市售饮料的检测方法。主要研究工作为:1.应用GUASSIAN软件及密度泛函理论,结合量子化学计算方法,对合成食品色素胭脂红和新红的分子空间结构模型进行了参数优化,计算得到了它们的振动情况、前线分子轨道能量和荧光发射光谱,得到两种色素荧光峰值波长计算值与实验值的相对误差分别为3.8%和0.78%。并且,对常被非法添加于食品的工业色素苏丹红I~III也用类似的方法进行了量子计算,计算结果与实验结果吻合。2.实验测定了11种目前国家允许添加的合成食品色素溶液的荧光偏振光谱。重点分析了新红和赤藓红分子在激发态寿命期间的偶极矩变化,得到两者相应发射偶极矩的平均角位移分别为3.91°和9.25°,从而推断得到新红和赤藓红分子的空间结构。由此,建立了一种基于荧光偏振特性分析合成食品色素分子空间结构的方法。3.分别测定了11种合成食品色素的三维常规和三维同步荧光光谱,提取了荧光特征参数,在此基础上研究了色素的检测方法。应用二阶校正算法对诱惑红与日落黄和亮蓝混合溶液的三维光谱数据进行了计算分析,得到各色素浓度,平均相对误差在3.0%以内。对苋菜红和亮蓝混合溶液计算得到色素浓度的平均相对误差为11%。进一步,应用同步光谱数据进行了相同算法的计算分析,得到苋菜红色素浓度的平均相对误差为4.0%,表明,同步光谱能有效解决光谱重叠问题,在检测中更有优势。由此,建立了荧光光谱结合二阶校正算法的色素检测方法,实现了对混合色素溶液中各组分的定性和定量测定。4.基于同步荧光光谱,应用平行因子算法,测定了市售鸡尾酒中苋菜红的浓度,平均相对误差为4.0%;基于导数荧光光谱,应用主成分分析方法,对市售苹果汁饮料进行了分类鉴别,正确率达到100%;对中成药六味地黄丸进行了质量鉴别,得到有意义的结果。由此表明,荧光光谱技术结合多变量统计分析算法,可以实现液态混合物的有效检测。本文的研究结果为荧光光谱技术应用于液态混合物的检测提供了技术支持,也可为复杂液态混合物检测方法的研究提供参考。
[Abstract]:In this paper, the theory and application basis of liquid mixture detection method and system are studied. The fluorescence spectrum mechanism of synthetic food pigment and the fluorescence polarization characteristics of synthetic food pigment solution were studied by combining the experimental measurement with quantum calculation, and the fluorescence spectrum technique was combined with the multivariate statistical analysis algorithm. The determination method of each component in synthetic food pigment mixed solution and the determination method of commercial beverage were studied. The main research work is: 1. Using GUASSIAN software and density functional theory, the molecular spatial structure models of synthetic food pigment carmine and new red were optimized by using quantum chemical calculation method, and their vibration was calculated. The relative errors between the calculated and experimental values of fluorescence peak wavelengths of the two pigments are 3.8% and 0.78%, respectively, according to the frontier molecular orbital energy and fluorescence emission spectra. In addition, the quantum calculation of industrial pigment Sudan red Ig III, which is often illegally added to food, is carried out using a similar method. The calculated results are in good agreement with the experimental results. The fluorescence polarization spectra of 11 kinds of synthetic food pigment solutions allowed by our country were measured experimentally. The dipole moment variation of the new red and red molecules during the excited lifetime is analyzed. The average angular shifts of the corresponding emission dipole moments are 3.91 掳and 9.25 掳, respectively, and the spatial structure of the new red and red molecules is inferred. Therefore, a method based on fluorescence polarization characteristics to analyze the molecular spatial structure of food pigment was established. The three dimensional conventional and three dimensional synchronous fluorescence spectra of 11 kinds of synthetic food pigments were determined, and the fluorescence characteristic parameters were extracted. Based on this, the detection method of pigment was studied. Three-dimensional spectral data of seductive red and sunset yellow and bright blue mixed solution were calculated and analyzed by the second-order correction algorithm. The average relative error was less than 3.0%. The average relative error of pigment concentration in amaranth and bright blue mixed solution was 11%. Furthermore, the calculation and analysis of the same algorithm based on the synchronous spectral data show that the average relative error of the concentration of amaranth red pigment is 4.0, which shows that the synchronous spectrum can effectively solve the problem of spectral overlap and has more advantages in detection. Therefore, a new method of pigment detection based on fluorescence spectrum and second-order correction algorithm was established, and the qualitative and quantitative determination of each component in the mixed pigment solution was realized. Based on synchronous fluorescence spectrum and parallel factor algorithm, the concentration of amaranth in commercial cocktails was determined with an average relative error of 4.0. Based on derivative fluorescence spectrum and principal component analysis, apple juice was classified and identified. The quality of Liuwei Dihuang pills was identified and significant results were obtained. It is shown that the fluorescence spectrum technique combined with multivariate statistical analysis algorithm can effectively detect liquid mixtures. The results of this paper provide technical support for the application of fluorescence spectroscopy in the detection of liquid mixtures, and can also provide a reference for the study of detection methods of complex liquid mixtures.
【学位授予单位】：江南大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O657.3;TS264.4

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