Graphene oxide modified U-shaped polymer optical fiber biosensor for hemoglobin sensing.

Area of Science:

• Biomedical Engineering
• Materials Science
• Optical Sensing

Background:

• Polymer optical fiber (POF) sensors offer flexibility and cost-effectiveness for biosensing.
• Integrating nanomaterials like graphene oxide (GO) and polyvinyl alcohol (PVA) with POF for hemoglobin detection is an underexplored area.
• Early detection of cancer relies on sensitive and selective biosensing methods.

Purpose of the Study:

• To develop and demonstrate a novel graphene oxide/polyvinyl alcohol (GO/PVA)-coated U-bent POF sensor.
• To achieve sensitive, repeatable, and selective detection of hemoglobin.
• To explore the potential of this sensor for early cancer diagnosis.

Main Methods:

• Fabrication of a U-bent POF coated with GO/PVA.
• Functionalization of the U-bent core and sputter-coating with a gold layer for surface plasmon resonance (SPR).
• Thermal deposition of the GO/PVA layer to impart analyte sensitivity.

Main Results:

• The GO/PVA-coated U-bent POF sensor demonstrated high sensitivity to refractive index variations (3949.14 nm/RIU).
• The sensor achieved a maximum sensitivity of -16.10 nm/(mg/ml) for hemoglobin with a 3-minute response time.
• The sensor exhibited approximately five times greater selectivity for hemoglobin over other plasma proteins.

Conclusions:

• The all-polymer U-shaped sensor shows significant potential as a competitive optical biosensing platform.
• This development advances the application of optical fiber sensors in biosensing.
• The sensor is a promising tool for hemoglobin detection in early cancer diagnosis.