Surface plasmon resonance biosensor based on graphene oxide/silver coated polymer cladding silica fiber

A graphene oxide/silver coated polymer cladding silica fiber optical surface plasmon resonance (SPR) human IgG detection biosensor with a high sensitivity and a low limit of detection is presented. Due to the graphene oxide (GO), the intensity of the confined electric field surrounding the sensing layer can be enhanced, the sensitivity of refractive index (RI) of the graphene oxide/silver SPR sensor reached 3311 nm/RIU in the RI range of 1.3334-1.3731 compared with 2875 nm/RIU in the range of 1.3328-1.3739 of the silver film SPR sensor. Afterwards, SPR optical fiber biosensor was developed based on graphene oxide/silver coated optical fiber when staphylococcal protein A and goat anti-human IgG were immobilized on the surface of the graphene oxide film. The sensor can be used to detect different concentrations of human IgG, a high sensitivity of 0.4985 nm/(μg/mL) and a low limit of detection 0.04 μg/mL were observed. Therefore, the graphene oxide/silver film SPR human IgG detection biosensor with high sensitivity and low limit of detection shows a great promise for the future biochemical and biomedical application.