基于表面增强拉曼散射的甜味剂糖精钠检测研究
时间:2020-06-21 14:37 来源:毕业论文 作者:毕业论文 点击:次
| 摘要 表面增强拉曼散射技术(SERS) 目前被广泛使用用于生物检测和医药诊断等领域，具有检测速度快、灵敏度高、检出限低等优势。本论文首先采用甲醇与丙酮混合有机溶液对高灵敏度 SERS 活性基底进行表面改性，当甲醇与丙酮的体积比为3:7 时，探针分子BPE的检测限可达到10-8 mol/L，相比于未经过表面改性处理的基底性能至少提高了 100 倍。然后通过密度泛函理论模拟计算糖精钠分子的振动模型，确定了糖精钠的主要特征峰位于 535 cm-1，594 cm-1，611 cm-1，705 cm-1，1013 cm-1等，并对其振动模式进行了归属；最后利用表面增强拉曼散射技术对不同浓度的甜剂糖精钠溶液进行了定量检测，结论表明糖精钠溶液各个特征峰信号随着溶液浓度的升高呈线性增强，其检测限为2 mg/L。研究结果为食品添加剂安全检测提供了新的分析方法与检测手段。 该论文有图15 幅，表3 个，参考文献29 篇。 51394 毕业论文关键词：表面增强拉曼光谱 糖精钠 表面改性 Study on Detection of Saccharin Sodium Based on Surface Enhanced Raman Scattering Abstract Surface enhanced Raman scattering (SERS) has been widely used in biological detection and medical diagnosis, etc., with the advantages of fast detection, high sensitivity and low detection limit. In this paper, the high sensitivity SERS active substrate was modified by the mixed organic solution of methanol and acetone, when the methanol: acetone is 3:7 (v:v), the detection limit of BPE can reach 10-8 mol/L, and the intensity compared to the substrate without surface modification improved at least 100 times. Then the molecular vibration model of sodium saccharin was calculated by density functional theory, the main characteristic peaks of saccharin sodium locate at 535 cm-1，594 cm-1，611 cm-1，705 cm-1，1013 cm-1, and respectively the vibration mode corresponding to the characteristic peaks. Finally, different concentrations of sweetener saccharin sodium solution was detected through surface enhanced Raman scattering technology. The results showed that each characteristic peak signal of sodium saccharin solution increased linearly with the increasing of the solution concentration, and the detection limit of saccharin sodium solution is 2 mg/L. It will provide a new analysis method and detection technical means for food additives safety. Key Words ：Surface enhanced Raman spectroscopy Saccharin sodium Surface modification 目录 摘要I Abstract..II 目录III 图清单.IV 表清单..V 1引言...1 1.1甜剂的介绍与使用现状1 1.2甜剂的研究方法及研究意义2 1.3表面增强拉曼效应.3 1.4主要研究工作与创新.5 2银纳米阵列基板的表面改性...6 2.1表面改性的意义与原理6 2.2表面改性实验.8 2.3本章小结...14 3甜剂糖精钠的表面增强拉曼光谱研究.16 3.1实验材料...16 3.2实验仪器...16 3.3实验步骤...16 3.4结果与分析...18 3.5本章小结...22 4总结与展望..23 4.1总结23 4.2展望23 参考文献24
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