Biosensor Based on Self‐Assembled Films of Graphene Oxide and Polyaniline Using a Field‐Effect Device Platform. Issue 13 (1st February 2021)

• Record Type: Journal Article
• Authors: Oliveira, Danilo A.; Molinnus, Denise; Beging, Stefan; Siqueira, José R.; Schöning, Michael J.
• Other Names: Wagner Patrick guestEditor.; Walter Hassel Achim guestEditor.; Schöning Michael J. guestEditor.
• Is Part Of: Physica status solidi. Volume 218:Issue 13(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-02-01
• Subjects: capacitive electrolyte–insulator–semiconductor sensors -- graphene oxide -- layer‐by‐layer technique -- nanomaterials -- polyaniline; Solid state physics -- Periodicals; Solids -- Industrial applications -- Periodicals; 530.41
• DOI: 10.1002/pssa.202000747
• Languages: English
• ISSNs: 1862-6300

Abstract

Abstract : A new functionalization method to modify capacitive electrolyte–insulator–semiconductor (EIS) structures with nanofilms is presented. Layers of polyallylamine hydrochloride (PAH) and graphene oxide (GO) with the compound polyaniline:poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) (PANI:PAAMPSA) are deposited onto a p‐Si/SiO2 chip using the layer‐by‐layer technique (LbL). Two different enzymes (urease and penicillinase) are separately immobilized on top of a five‐bilayer stack of the PAH:GO/PANI:PAAMPSA‐modified EIS chip, forming a biosensor for detection of urea and penicillin, respectively. Electrochemical characterization is performed by constant capacitance (ConCap) measurements, and the film morphology is characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM). An increase in the average sensitivity of the modified biosensors (EIS–nanofilm–enzyme) of around 15% is found in relation to sensors, only carrying the enzyme but without the nanofilm (EIS–enzyme). In this sense, the nanofilm acts as a stable bioreceptor onto the EIS chip improving the output signal in terms of sensitivity and stability. Abstract : Sensing properties toward pH, urea, and penicillin detection of nanostructured films of polyallylamine hydrochloride (PAH) and graphene oxide (GO) with the compound polyaniline:poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) (PANI:PAAMPSA), deposited onto a p‐Si/SiO2 chip using the layer‐by‐layer technique (LbL) and a capacitive electrolyte–insulator–semiconductor (EIS) structure as a detection platform, are reported.