A Graphene-PEDOT:PSS Modified Paper-Based Aptasensor for Electrochemical Impedance Spectroscopy Detection of Tumor Marker

Abstract

A graphene and poly (3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) modified conductive paper-based electrochemical impedance spectroscopy (EIS) aptasensor has been successfully fabricated by a simple and continuous coating process. A graphene/PEDOT:PSS modified paper electrode forms the nanocomposite providing a conductive and sensitive substrate for further aptamer functionalization of the biosensor. This low-cost paper-based aptasensor exhibits its sensitivity to carcinoembryonic antigens (CEA) in standard buffer solutions and human serum samples in a linear range of 0.77–14 ng·mL−1. The limit of detection (LOD) is found to be 0.45 ng·mL−1 and 1.06 ng·mL−1 for CEA in both samples, separately. This aptamer-based sensing device was also evaluated and received a good correlation with the immunoassay detection method. The proposed paper-based aptasensor has demonstrated its potential as a rapid simple point-of-care analytical platform for early cancer diagnosis in less developed areas where manufacturing facilities, analytical instruments, and trained specialists are limited.

Design Strategies for Electrochemical Aptasensors for Cancer Diagnostic Devices

“…A variety of nanomaterials and nanocomposites was used both for the aptamer immobilisation and labelling: graphene-based nanomaterials [ 247 , 248 , 249 , 250 , 251 , 252 , 253 , 254 , 255 , 256 ], nanocomposite Zr metal–organic frameworks with Ag nanoclusters [ 257 ], and avidin-gated mesoporous silica nanoparticles [ 258 ].…”

“…A conductive strip paper-based aptasensor detected CEA in the 0.77 to 14 ng mL −1 range, with LOD of 0.45 ng mL −1 and 1.06 ng mL −1 in buffer and human serum samples [ 256 ]. The sensing layer represented graphene and poly (3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) nanocomposite, (3-aminopropyl) triethoxysilane (APTES), succinic anhydride (SA), DNA aptamers, and BSA.…”

Cytokine and Cancer Biomarkers Detection: The Dawn of Electrochemical Paper-Based Biosensor

“…Apart from NMNPs, non-NMNPs such as carbon nanotubes and graphene have also been reported as alternatives for surface modification of electrodes for improved detection [71][72][73][74][75]. For instance, an amplified signal was recorded when graphene oxide nanoflakes and zeolite nanocrystals were introduced onto the electrode surface of a paper sensor due to high electron transfer kinetics and larger surface area of the nanocomposites [76].…”

Highly Conductive Polymer PEDOT: PSS - Application in Biomedical and Bioelectrochemical Systems

“…The detection limit for clenbuterol was 0.196 ng/ml. The article [36] described the aptasensor based on electrochemical impedance spectroscopy. The paper electrode was modified with PEDOT: PSS and grapheme to provide conductivity and sensitivity, the surface was then functionalized with amino-and carboxyl groups, and then with aptamers.…”