摘要： 针对生物过程反应底物含量的实时测量，设计了一种在线式傅里叶变换红外光谱仪及衰减全反射(attenuated total reflectance，ATR)探头。(1) 光谱仪采用双立体角镜和平面镜相组合的方法，设计了一种高性能干涉仪系统;采用了光路折叠方式，使干涉仪结构紧凑;采用了双立体角镜，大大减少了动镜运动过程中存在的旋转、倾斜等因素影响;采用平行四边形摆动柔性支撑装置来支撑动镜，使动镜移动时无摩擦，无抖动，运行平稳;采用ZnSe分束器，使仪器抗潮湿性能大大增强;采用分束器60°光入射方式，提高了光通量。(2) 该工作设计的一种结构简单、光通量大、经济实用的ATR原位测量探头，入射光和出射光的传输均利用了大口径内镀中红外高反膜光导管作为ATR探头的红外光传输介质，从而大大降低红外光在光导管内壁多次反射后的能量损失，使得ATR探头具有高光通量，提高了信号强度，使信号的检出更加容易。最后采用灵敏度高的MCT(碲镉汞)检测器实现红外干涉信号的收集，使得检测效果更好。实验结果表明，系统具有防潮性能出色，光通量大，在线测量等优点。所设计在线式傅里叶红外光谱仪，能够较好的完成生物反应器内甘油等常见反应物底物的实时测量，在生物在线分析、化学物质检测、材料分析学等诸多领域具有较好的应用前景。
关键词：生物过程;傅里叶变换红外光谱仪;ATR探头;在线监测
Abstract：An online Fourier Transform Infrared Spectrometer and an ATR (Attenuated Total Reflection) probe, specifically at the application of real time measurement of the reaction substrate concentration in biological processes, were designed. (1) The spectrometer combined the theories of double cube-corner reflectors and flat mirror, which created a kind of high performance interferometer system. The light path folding way was utilized to makes the interferometer compact structure. Adopting double cube-corner reflectors, greatly reduces the influence of factors in the process of moving mirror movement such as rotation, tilt, etc. The parallelogram oscillation flexible support device was utilized to support the moving mirror moves. It cancelled the friction and vibration during mirror moving, and ensures the smooth operation. The ZnSe splitter significantly improved the hardware reliability in high moisture environment. The method of 60° entrance to light splitter improves the luminous flux. (2）An ATR in situ measuring probe with simple structure, large-flux, economical and practical character was designed in this article. The transmission of incident light and the light output utilized the infrared pipe with large diameter and innerplanted-high plating membrane, which conducted for the infrared transmission media of ATR probe. It greatly reduced the energy loss of infrared light after multiple reflection on the inner wall of the light pipe. Therefore, the ATR probe obtained high flux, improved the signal strength, which make the signal detected easily. Finally, the high sensitivity of MCT (Mercury Cadmium Telluride) detector was utilized to realize infrared interference signal collection, and improved the data quality of detection. The test results showed that the system yields the advantages of perfect moisture-proof performance, luminous flux, online measurement, etc. The designed online Fourier infrared spectrometer can real-time measured common reactant substrates such as glycerin in the bioreactor under high quality. There is a large potential market, such as online analysis in biological, chemical testing and material analysis.
