正交型发光二极管诱导荧光检测器的研制

摘要

A small and low power efficient fluorescence detector was developed using light-emitting diode as excitation light source,multimode optical fiber as excitation light and capillary as testing pool.Based on orthog-onal optical arrangement,a homemade high precision machined platform was utilized in the self-alignment and self-calibration of optical fiber,capillary,and fluorescent collection lens.To evaluate the performance of the de-tector,a flow injection moldel was applied using sodium fluorescence as standard sample.Results showed that, the limit of detection(LOD)was 6.75×10-8 mol·L-1 (S/N =3),linear relationship was good in the range of 1.35×10-7 ~43.2×10-7 mol·L-1 (R 2 =0.9992)with good stability(RSD<1%).Four kinds of amino acids labeled by fluorescein isothiocyanate(FITC)were separated by the detector via HPLC method.%以发光二极管为激发光源，以多模光纤代替透镜组作为激发光路，利用毛细管作为检测池，研制了一台小型、低功耗的荧光检测器。采用正交型光路设计，借助高精度机械加工的自校准平台，使光纤-毛细管-荧光收集透镜实现自校准。采用流动注射模式，以荧光素钠为标准样品对该检测器性能进行了测试，最低检测限为6．75×10－8 mol· L－1（S／N ＝3），在1．35×10－7～43．2×10－7 mol·L－1范围内线性关系良好（R 2＝0．9992），稳定性良好（RSD＜1％）。结合高效液相色谱系统，分离了异硫氰酸荧光素标记的4种氨基酸。