4:00 PM - 6:00 PM
▼ [20p-P11-3] Improving Surface Plasmon Resonance Immunosensor Based on Graphene Oxide/PEDOT/PSS Film
Keywords:Graphene oxide,Surface plasmon resonance
Obtaining better limit of detection and sensitivity in determination of human IgG was observed by an electrochemical-surface plasmon resonance (EC-SPR) immunosensing system. In this work, the EC-SPR immunosensor constructed with graphene oxide/poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (GPO/PEDOT/PSS) was demonstrated. The GPO/PEDOT/PSS film was prepared by electropolymerization of GPO/EDOT/PSS aqueous solution on a gold-coated high refractive index glass slide. The deposited film was well dispersed on the substrate, on which film morphology could be further modified by applied potential to obtain a strong SPR response, while the carboxylic groups of GPO particles offered the covalent attachment of anti-IgG. The resultant immunosensing platform was systematically characterized by morphological, voltammetric and SPR techniques, and then used for detection of IgG. This EC-SPR immunosensor exhibited a satisfied sensitivity and specificity toward the determination. The detection limit and sensitivity of the sensor were studied by controlling the morphology of the GPO/PEDOT/PSS film with different applied potentials. In comparison among an open circuit and applied potential range (-1.0 to 1.0 V), the EC-SPR immunosensor at a applied potential of 1.0 V exhibited the best sensitivity of 5.98x10-3 µg.ml-1.cm-2 with the lowest detection limit of 0.33 µg.mL-1, suggesting good device performances in the detection of human IgG at physiological level. All conditions showed a linear calibration range of the detection from 1.0 µg.mL-1 to 10 µg.mL-1. Consequently, the proposed method is potentially useful for clinical applications.