Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India.
Biosens Bioelectron. 2011 Mar 15;26(7):3367-70. doi: 10.1016/j.bios.2010.12.014. Epub 2010 Dec 16.
A novel label-free technique for the detection of pathogens based on evanescent wave absorbance (EWA) changes at 280 nm from a U-bent optical fiber sensor is demonstrated. Bending a decladded fiber into a U-shaped structure enhances the penetration depth of evanescent waves and hence sensitivity of the probe. We show that the enhanced EWA response from such U-bent probes, caused by the inherent optical absorbance properties of bacterial cells or biomolecules specifically bound to the sensor surface, can be exploited for the detection of pathogens. A portable optical set-up with a UV light emitting diode, a spectrometer and U-bent fiber optic probe of 200 μm core diameter, 0.75 mm bend radius and effective probe length of 1cm demonstrated an ability to detect less than 1000 cfu/ml.
基于 U 型光纤传感器中 280nm 倏逝波吸收（EWA）变化的新型无标记病原体检测技术得到了验证。将去包层光纤弯曲成 U 型结构可以增强倏逝波的穿透深度，从而提高探针的灵敏度。我们表明，由于细菌细胞或与传感器表面特异性结合的生物分子的固有光吸收特性，这种 U 型弯曲探针产生的增强的 EWA 响应可用于检测病原体。一个带有紫外发光二极管、分光光度计和 200μm 芯径、0.75mm 弯曲半径、有效探针长度为 1cm 的 U 型光纤探针的便携式光学装置，可检测到低于 1000cfu/ml 的浓度。
