Dual Kretschmann and Otto configuration fiber surface plasmon resonance biosensor

Abstract

We present a dual-resonance fiber surface plasmon resonance (SPR) sensor for biological analysis. The sensing element was fabricated by sequentially sputtering layers of indium tin oxide (ITO) (100 nm thickness) and Au (35 nm thickness) on the surface of an optical fiber. The refractive index dispersion effect of ITO material led to resonances in the near infrared and visible wavelength regions. The refractive index of ITO is larger than the optical fiber in visible spectral area (400 to 733nm), such that the structure is a typical Kretschmann configuration surface plasmon resonance sensor. However, an Otto configuration is observed in the near infrared area (NIR) due to the ITO refractive index being smaller than the fiber core. We characterized the sensor performance by measuring bulk refractive index (RI) sensitivity in the two configurations, which were 1345 nm/RIU in the Kretschmann configuration and 1100 nm/RIU in the Otto configuration. In addition, this sensor was applied for real-time and label-free monitoring of the IgG/anti-IgG biomolecular interaction. As a robust and ultra-compact SPR sensor, which possesses wide detection range and is highly sensitive, this fiber SPR sensor can be applied for real-time biological analysis and monitoring.

Fluoride Fiber-Based Plasmonic Biosensor with Two-Dimensional Material Heterostructures: Enhancement of Overall Figure-of-Merit via Optimization of Radiation Damping in Near Infrared Region

“…It is important to appreciate that the interaction volume plays an important role in plasmonic sensor characteristics. Some of the research works based on fiber-optic SPR sensors have also demonstrated the field distribution along the analyte side under resonance conditions [40,41]. The field enhancement towards the analyte region increases the interaction volume.…”

Real-time biodetection using a smartphone-based dual-color surface plasmon resonance sensor

“…It illustrates that the normalized intensity shift as a function of RI can be linear fitted in the RI range of 1.326 to 1.351, which can be used for many biochemical samples measurement. 25,26 In the RI range of 1.326 to 1.351, the system provides a sensitivity of 11.542/RIU. Analysis of the baseline noise was also performed.…”

Совмещение Конфигураций Отто И Кретчмана Для Возбуждения Различных Мод Поверхностных Плазмон-Поляритонов

“…Такой резонанс можно использовать как опорный при сравнении с изменением положения резонанса по Кретчману, что позволит повысить точность и стабильность работы двухрезонансной структуры в режиме сенсора по сравнению с однорезонансной. Отметим, что другими исследовательскими группами также предпринимаются подобные шаги по созданию двухрезонансных плазмонных систем, совмещающих резонансы Отто и Кретчмана, например, на спектральных датчиках оптоволоконного типа с буферным слоем, имеющим сильную дисперсию диэлектрической проницаемости [11].…”