Quantitative measurement of human anti-HCV Core immunoglobulins on an electrical biochip platform

Abstract

The importance of early diagnosis devices increased continuously in the last two decades and plays an important role in medical care. Early stage diagnosis of e.g. ovarian cancer, HCV-infection or HIV-infection increased the survival rate of patients significantly. In parallel there is a trend leaving centralized diagnostic laboratories in order to get closer to the patient to perform analysis of even complex parameters in the field. This often saves time, increases the prognosis of the patient significantly and is cheaper in many cases. In this study we employ a rapid and cost-effective detection system based on electrical biochip technology for decentralized detection of anti-HCV Core immunoglobulins (HCV antibodies). In this system the qualitative and quantitative detection of virus-specific antibodies is done by an ELISA directly on a gold electrode array utilizing HCV Core as capture antigen. The biochip allows antibody detection within 20 min. Signal amplification was done by enzyme labelling and by “Single Electrode Redox Cycling”. This method enhances current signals up to 40-fold in comparison to simple oxidation. The sensitivity of this approach is therefore comparable to a standard microtiter plate based ELISA with a 9-fold saving of assay time. This biochip system allows serum or whole blood analysis with no signal loss or increasing background caused by the red blood cells. Fields of application can be hospital emergency units where only single detections have to be conducted in a quick manner or by the general practitioner.