Department of Electronics and Communication Engineering, National Institute of Technology Karnataka, Surathkal 575025, India.
Department of Electronics Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad 826004, Jharkhand, India.
Rev Sci Instrum. 2020 Dec 1;91(12):125001. doi: 10.1063/5.0020571.
In this work, a TiO coated etched long-period grating (e-LPG) fiber optic biosensor is developed for the detection of Escherichia coli (E. coli) bacteria in food items. Label-free Escherichia coli bacteria monitoring is done over the detection range of 0 cfu/ml-50 cfu/ml using an advanced spectral interrogation mechanism. The thin film deposition of 40 nm TiO over the e-LPG is confirmed by the microscopy method, such as scanning electron microscopy. In our proposed biosensor design, T4-bacteriophage is covalently immobilized over the TiO coated fiber surface. This biosensor system has reached sensitivity at 2.55 nm/RIU. Our experiments confirm the resolution and the limit of detection (3σ/S) of 0.0039 RIU and 10.05 ppm, respectively. The proposed biosensor with enhanced sensitivity is suitable for monitoring harmful pathogens/infectious agents in various food products.
在这项工作中，开发了一种涂覆 TiO 的刻蚀长周期光栅（e-LPG）光纤生物传感器，用于检测食品中的大肠杆菌（E. coli）细菌。使用先进的光谱询问机制，在 0 cfu/ml-50 cfu/ml 的检测范围内进行无标记的大肠杆菌细菌监测。通过显微镜方法（如扫描电子显微镜）确认 e-LPG 上的 40nm TiO 薄膜沉积。在我们提出的生物传感器设计中，T4 噬菌体通过共价键固定在涂覆 TiO 的光纤表面。该生物传感器系统的灵敏度达到了 2.55nm/RIU。我们的实验分别证实了分辨率和检测限（3σ/S）为 0.0039 RIU 和 10.05ppm。具有增强灵敏度的这种生物传感器适用于监测各种食品中的有害病原体/传染性物质。
