Diagnostic tests for hepatitis C: Recent trends in electrochemical immunosensor and genosensor analysis

Table 1 Recent developments on hepatitis C virus detection by electrochemical immunosensors

Electrode	Immunosensor format	Antigen	Labelled system	Technique	Performance of the immunosensor	Ref.
3-Mercaptopropionic, acid was assembled on gold electrode to form a self-assembled monolayer	-	Thionine HCV horseradish peroxidase (HRP) antibody	-	Cyclic voltammetry and Linear scan voltammetry	The linearity of Hepatitis C in the range of 3.2 to 16 mg/L with the correlation coefficient of 0.995	[90]
Glassy carbon electrode modified with a nanocomposite (gold/zirconia/chitosan)	Sandwich-type	HCV core	Label-free	Cyclic voltammetry, Electrochemical impedance spectroscopy	Stability: 98.5% (30 d)	[91]
					Detection limit: 0.17 ng/mLRSD (different electrodes): 5.1%, 3.9% and 4.8% for 2, 32 and 128 ng/mL HCV core antigen
GMCs-MB nanocomposite	Sandwich-type	HCV core	Horseradish peroxidase-DNA-coated CMWNTs as a secondary antibody layer	Cyclic voltammetry, Electrochemical impedance spectroscopy	Stability: 91.6% (10 d)	[92]
					Detection limit: 0.01 pg/mL
					Regeneration: 8 mol/L urea solution (RSD, 3.1%)
Glassy carbon electrode was modified with an Au-MoO3/Chitosan nanocomposite	Sandwich-type	HCV non-structural 5A protein	Horseradish peroxidase-labelled antibody	Cyclic voltammetry, Chronoamperometry, Electrochemical impedance spectroscopy	Detection range: 1.0 ng/mL-50 μg/mL	[93]
Silk fibroin nanostructured films on screen-printed carbono electrode	Direct assay	HCV non-structural 5A protein	Label-free	Cyclic voltammetry	Sensitivity: 28 μA/μgDetection range: 0 μg/mL-0.2 μg/mL	[94]

HCV: Hepatitis C virus; GMCs-MB: Graphitized mesoporous carbon-methylene blue; CMWNTs: Carboxyl multi-wall carbon nanotubes.