A reflective optical fiber SPR sensor with surface modified hemoglobin for dissolved oxygen detection

A new dissolved oxygen sensor based on optical fiber surface plasmon resonance (SPR) theory and the mechanism of oxygen transporting by hemoglobin was proposed and demonstrated. Gold film was coated on the surface of the optical fiber sensing area, and hemoglobin was modified on the surface of the gold film. The experimental results show that the sensor has good linearity and the limit of detection (LOD) of the sensor is 0.03 mg/L. In addition, in order to enhance the sensitivity of the sensor, the carbon nanotubes were modified on the surface of the gold film of the fiber, and then the hemoglobin was modified in the outermost layer. Through experiments, it was found that the sensitivity of the sensor which modified with carbon nanotubes is 2.8-folds higher than that only modified hemoglobin, the linearity is better, and the LOD is reduced to 0.01 mg/L. (C) 2021 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University.