中国激光, 2013, 40 (9): 0915001, 网络出版: 2013-08-27
非法食品添加剂拉曼检测中的荧光抑制
Fluorescence Rejection in Raman Testing of Illegal Food Additives
光谱学 拉曼光谱 荧光抑制 移频激发 外腔半导体激光器 反卷积 spectroscopy Raman spectroscopy fluorescence rejection shifted excitation external cavity diode laser deconvolution
摘要
基于外腔半导体可调谐激光器(ECDL)设计了一种结构紧凑的移频激发差分拉曼光谱(SERDS)法的多波长光源,具有15 nm的波长调谐范围,优于0.2 nm的线宽以及最大80 mW的输出功率。提出用多重约束反卷积算法对SERDS差分光谱进行复原处理,可有效抑制噪声。应用SERDS方法对苏丹红I号、罗丹明B、三聚氰胺、乌洛托品等非法食品添加剂进行了测量,证明该方法不仅能很好地去除荧光背景,而且能大幅提高检测信噪比。
Abstract
A compact shifted excitation Raman difference spectroscopy (SERDS) multi-wavelength light source based on tunable external cavity semiconductor laser (ECDL) is designed. A wavelength tuning range of 15 nm can be achieved, with the laser spectral line-width less than 0.2 nm and output power up to 80 mW. We also developed a deconvolution algorithm with multiple constraints to process the difference spectrum of SERDS, which can suppress the noises efficiently. This SERDS system is used to test several illegal food additives (sudan I, rhodamine B, melamine, hexamine). The results show that this method can effectively remove the background fluorescent and significantly increase the signal-to-noise ratio of Raman detection.
周红武, 蔡志坚, 吴建宏. 非法食品添加剂拉曼检测中的荧光抑制[J]. 中国激光, 2013, 40(9): 0915001. Zhou Hongwu, Cai Zhijian, Wu Jianhong. Fluorescence Rejection in Raman Testing of Illegal Food Additives[J]. Chinese Journal of Lasers, 2013, 40(9): 0915001.