On-chip integrated graphene aptasensor with portable readout for fast and label-free COVID-19 detection in virus transport medium

Abstract

Graphene field-effect transistor (GFET) biosensors exhibit high sensitivity due to a large surface-to-volume ratio and the high sensitivity of the Fermi level to the presence of charged biomolecules near the...

Ultrasensitive detection of SARS-CoV-2 spike protein by graphene field-effect transistors

“…8E the transfer curves of the GFET array in presence and absence of 120 aM of Ecto S in diluted saliva are reported (which would be equal to 1 virus per μL if one viral particle contains 100 surface spike proteins). 30,31 The ΔV CNP registered in artificial saliva is comparable to the one in PBS confirming the applicability of the biosensor in complex environments (Fig. 8F).…”

“…This relation can be explained by the Langmuir isotherm, which describes the absorption of a molecule over a surface, 29 and it is frequently reported for GFETs in which the sensing mechanism involves an adsorption/desorption step. 8,30 The ΔV CNP is linearly dependent from the logarithm of the concentration in the range from 2.4 to 720 aM (Fig. 8D).…”

Impedimetric Detection Based on Label-Free Immunoassay Developed for Targeting Spike S1 Protein of SARS-CoV-2

“…The detection of the SARS-CoV-2 virus using combinations of electrochemical techniques, such as voltametric [ 4 , 47 , 48 , 49 , 51 , 53 , 54 ], amperometric [ 5 , 9 , 52 ] and impedimetric [ 6 , 7 , 10 , 27 , 55 ] techniques, was explored for the determination of different bioreceptors of SARS-CoV-2. In comparison to previous studies reporting on the development of different techniques [ 8 , 56 , 57 , 58 , 59 ], the advantages of our label-free impedimetric immunosensor are listed as the simple preparation procedure with short preparation time (i.e., 3 h) and rapid analysis (only 6 min). Moreover, no surface modification using nanomaterials, such as graphene [ 8 , 56 ], graphene oxide [ 57 ] or gold nanoparticles [ 57 , 58 , 59 ], was applied in our study.…”

“…In comparison to previous studies reporting on the development of different techniques [ 8 , 56 , 57 , 58 , 59 ], the advantages of our label-free impedimetric immunosensor are listed as the simple preparation procedure with short preparation time (i.e., 3 h) and rapid analysis (only 6 min). Moreover, no surface modification using nanomaterials, such as graphene [ 8 , 56 ], graphene oxide [ 57 ] or gold nanoparticles [ 57 , 58 , 59 ], was applied in our study. In contrast to optical detection of SARS-CoV-2 [ 59 , 60 ], our assay is easy to apply without requiring any extra labels (such as fluorescent dye, peptide etc.).…”

Applications of Graphene in Five Senses, Nervous System, and Artificial Muscles

“…A miniaturized electrochemical sensor was packaged into a hand-held system, which supplies a user interface on a smartphone for diagnosis of coronavirus disease 2019 . Graphene based sensors have detected several viruses, including Zika virus, human immunodeficiency virus, and COVID-19 …”