Bronk K S, Michael K L, Pantano P, Walt D R
Max Tishler Laboratory for Organic Chemistry, Department of Chemistry, Tufts University, Medford, Massachusetts 02155, USA.
Anal Chem. 1995 Sep 1;67(17):2750-7. doi: 10.1021/ac00113a005.
Despite many innovations and developments in the field of fiber-optic chemical sensors, optical fibers have not been employed to both view a sample and concurrently detect an analyte of interest. While chemical sensors employing a single optical fiber or a noncoherent fiberoptic bundle have been applied to a wide variety of analytical determinations, they cannot be used for imaging. Similarly, coherent imaging fibers have been employed only for their originally intended purpose, image transmission. We herein report a new technique for viewing a sample and measuring surface chemical concentrations that employs a coherent imaging fiber. The method is based on the deposition of a thin, analyte-sensitive polymer layer on the distal surface of a 350-microns-diameter imaging fiber. We present results from a pH sensor array and an acetylcholine biosensor array, each of which contains approximately 6000 optical sensors. The acetylcholine biosensor has a detection limit of 35 microM and a fast (< 1 s) response time. In association with an epifluorescence microscope and a charge-coupled device, these modified imaging fibers can display visual information of a remote sample with 4-microns spatial resolution, allowing for alternating acquisition of both chemical analysis and visual histology.
尽管光纤化学传感器领域有许多创新和发展，但光纤尚未被用于观察样品并同时检测感兴趣的分析物。虽然采用单根光纤或非相干光纤束的化学传感器已应用于各种分析测定，但它们不能用于成像。同样，相干成像光纤仅用于其最初的用途，即图像传输。我们在此报告一种利用相干成像光纤观察样品并测量表面化学浓度的新技术。该方法基于在直径为350微米的成像光纤远端表面沉积一层薄的、对分析物敏感的聚合物层。我们展示了pH传感器阵列和乙酰胆碱生物传感器阵列的结果，每个阵列包含约6000个光学传感器。乙酰胆碱生物传感器的检测限为35微摩尔，响应时间快（<1秒）。与落射荧光显微镜和电荷耦合器件相结合，这些经过修饰的成像光纤能够以4微米的空间分辨率显示远程样品的视觉信息，从而实现化学分析和视觉组织学的交替采集。
