基于多通道模式滤光检测的同步分离分析光化学传感器的研究

【作者】 周征；

【导师】 王柯敏；

【作者基本信息】 湖南大学 ， 分析化学， 2001， 硕士

【摘要】 我们的研究工作是在新型光纤化学传感模式——模式滤光检测的基础上开展的。光纤模式滤光传感器是基于折射率变化的光化学传感器，本文旨在研究多通道模式滤光检测和将分离技术同此方法结合建立同步分离分析的传感器，主要工作围绕四个方面开展： 一、作者开展了多通道模式滤光检测的研究工作，同时还对多通道模式滤光进行了理论分析，在理想的条件下，即将入射的激光抽象地认为是绝对平行的光线；激光在光纤内传播不存在散射和吸收；光纤表面绝对平整，建立了多通道模式滤光的数学理论公式，并用理论公式合理地解释了一部分实验现象。首次在国际上明确提出了可以基于多通道模式滤光检测实现对样品的同步分离分析。 二、用多通道模式滤光检测方法对葡萄糖水溶液中葡萄糖的浓度进行了测定，检测范围从0.5％-20％(wt％)。在建立了标准工作曲线后，用三不同的检测通道对实际样品5％的葡萄糖注射液的测定都与药典法相吻合。实验还表明此多通道模式滤光仪器的响应迅速、重现性好。在实验的基础上论证多通道模式滤光检测可以实现对样品的同步分离分析。 三、为了在模式滤光传感器的环形空腔内实现分离功能，作者又对具有液相色谱功能的共价键合涂层进行了初步的研究。用共价键合的方法，在光纤和毛细管内壁共价固定了一层长链烷基的硅烷化试剂(WD-10)，在甲醇的水溶液为流动相的条件下，构造了一个开管的反相毛细管液相色谱。发现了乙醇、丁醇、苯甲醇的停留时间不一样，并从三个通道观察到了乙醇和丁醇在柱内不同位置的分离情况。初步证实了将长链烷基的硅烷化试剂(WD-10)共价固定在环形空腔内表面可以实现同步分离分析。 四、将毛细管电泳和基于折射率变化的多通道模式滤光检测结合起来， 实现对样品的同步分离分析。以模式滤光传感器的环形空腔作为毛细管电 泳的场所，它是由直径为530微米的毛细管和直径为400微米的光纤构成 的。在用 10InMHCI溶液为前导缓冲液，用 10InM Tris溶液为尾随缓冲液， 以环形毛细管等速电泳（CITP）的方式分离样品溶液中乙氨酸（9．7InM） 和丙氨酸（9．3InM），并从三个通道观察到了处于毛细管不同位置时样品溶 液中乙氨酸和丙氨酸的分离倩况。从不同通道的模式滤光信号都可以出乙 氨酸和丙氨酸浓度相近。更多还原

【Abstract】 With the base of the mode-filtered light detection, which belongs to the refraction index (RI) detection system, the research of novel optical fiber sensors and instruments has been done in this paper. Aim to built the sensors for simultaneous separation and analysis, the mode-filtered light detector has been combined with the separating technology.1.The theory of multichannel mode-filtered light detection has been studied in this paper. On the assumption that laser is a beam of parallel lines and no energy absorption occurs in the fiber whose surface is absolute smooth, the theoretical equations has been found from theoretic reasoning and has been used successfully to explain some of the experimental results. The sensor with synchronization of separation and analysis has been introduced for the foundation of the theoretical and experimental results.2.A novel mode-filtered light detection method is described in which an unjacketed optical fiber is inserted into a transparent capillary tube and three or more detection channels are set up on the capillary side for different distance from the port of fiber. With the present method and apparatus, glucose and glycerol have been determined, with good reproducibility, stability and a small volume. Furthermore, a real sample of glucose injection is measured for a detection volume of 5 iL, and an acceptable result is observed.3.With the immobilization of a separating function cladding in the annular column of the sensor, the sensor system with synchronization of separation and analysis has been established. After the annular column covalent has been bonded with silylanization reagent (WD-lO), an open tubular liquid chromatographic sensor are constructed. Using aqueous methanol solution as a mobile phase, retention times of alcohol, butanol, and benzyl alcohol are different. The separation process of sample contained alcohol and butanol is observed from three selected channels, and the results suggest that this method can reach the purpose of synchronization of separation and analysis.III4.The novel method for the synchronization of separation and analysis is described, in which the mode-filtered light detector is used as an on line detector of capillary electrophoresis, and an instrument has been established corresponding to this method. Instead of a round capillary, an annular column which is constructed by inserting a naked optical fibre (~=4OO~im) into the fused silica capillary (~53O~m), is used in the capillary electrophoresis. Using the capillary isotachophoresis in the annular column, a sample containing alanine (9.8mM) and glycin (10.0mM) is separated and analyzed simultaneously by the multichannel mode-filtered light detection. The signals from three channels show that the concentrations of two components in the sample are of similar intensity in different channels.更多还原