Yang Qingxin, Loock Hans-Peter, Kozin Igor, Pedersen David
Department of Chemistry, Queen's University, Kingston, ON, Canada.
Analyst. 2008 Nov;133(11):1567-72. doi: 10.1039/b806068a. Epub 2008 Sep 11.
Fiber Bragg Gratings (FBGs) are known to be sensitive acoustic transducers and have previously been used for the photoacoustic detection of small solid samples. Here, we demonstrate the use of an FBG as an on-line detector for liquid chromatography. The FBG was inserted into a silica capillary and the photoacoustic response from the effluent was generated by a 10 ns pulsed laser. The acoustic pulse was quantified by the FBG through a characteristic change in the reflection spectrum. Good repeatability and linear response were obtained over three orders of magnitude (R(2) > 0.99), and the limit of detection of Coumarin 440 was determined to be 5 microM. The technique was successfully coupled to high performance liquid chromatography and applied to on-line analysis of a three-compound solution. Photoacoustic detection in liquid chromatography using FBGs is a label-free method, which can be applied to the detection of any chromogenic compound irrespective of its fluorogenic properties. It is a simple, inexpensive, and inherently micron-sized technique, insensitive to electromagnetic interference.
光纤布拉格光栅（FBGs）是已知的灵敏声换能器，此前已用于小固体样品的光声检测。在此，我们展示了将FBG用作液相色谱的在线检测器。将FBG插入石英毛细管中，由10 ns脉冲激光产生流出物的光声响应。FBG通过反射光谱的特征变化对声脉冲进行定量。在三个数量级上获得了良好的重复性和线性响应（R(2) > 0.99），香豆素440的检测限确定为5 microM。该技术成功与高效液相色谱联用，并应用于三化合物溶液的在线分析。使用FBG进行液相色谱中的光声检测是一种无标记方法，可应用于任何发色化合物的检测，而不论其荧光性质如何。它是一种简单、廉价且本质上为微米级的技术，对电磁干扰不敏感。
