Rapid detection of different human anti-HCV immunoglobulins on electrical biochips

Abstract:

The detection of hepatitis C virus (HCV) in the blood of patients is currently based on immunological assays (enzyme-linked immunosorbent assay [ELISA] and recombinant immunoblot assay) that use different HCV epitopes to detect anti-HCV antibodies, and these tests usually require laboratories and trained personnel. The ELISA-based systems are also time consuming. Portable diagnostic devices offering rapid test results would therefore be advantageous in the field of medical care. To facilitate the fast and reliable diagnosis of HCV, we used a miniaturized automated system based on a cartridge with an integrated electrical biochip for the decentralized detection of anti-HCV antibodies against the Core, NS3, and NS4A proteins. This system allows the detection of virus-specific antibodies in 2 μL of serum or whole blood within 15 minutes using an ELISA directly on a gold electrode array containing HCV proteins as the capture antigen. The sensitivity of this system is comparable with standard microtiter plate ELISAs, but the duration of the novel assay is 5%–6% that of standard ELISAs.

Keywords::

• ELISA
• point-of-care
• cartridge
• lab-on-chip

Acknowledgments

We thank Michael Küpper (IMB, RWTH Aachen University) for assistance with mass spectrometry and its evaluation, Thorsten Sieben (Uniklinik RWTH Aachen) and Severin Schmies (Fraunhofer IME, Aachen) for helping with the fermentation and purification of both NS proteins, and Dr Richard Twyman for critical reading of the manuscript.

Disclosure

The authors report no conflicts of interest in this work.

Supplementary materials

Consensus sequence NS3

N- -> C-terminal direction

APITAYAQQTRGLLGTIVTSLTGRDKNEVEGEVQVLSTATQTFLGTTINGVMWTVYHGAGSKTLAGPK GPVIQMYTNVDQDLVGWPAPPGAKSLTPCTCGSSDLYLVTRHADVIPARRRGDTRGSLLSPRPISTLK GSSGGPVLCPSGHAVGIFRAAVCTRGVAKALDFVPVESLETTMRSPVFTDNSTPPAVPQTYQVGHLH APTGSGKSTKVPAAYAAQGYKVLVLNPSVAATLGFGAYMSKAHGIDPNIRTGVRTITTGAPITYSTYGK FLADGGCSGGAYDIIICDECHSTDATTILGIGTVLDQAETAGARLVVLATATPPGSVTVPHPNIEEVALP TTGEIPFYGKAIPLELIKGGRHLIFCHSKKKCDELAKQLTSLGLNAVAYYRGLDVSVIPTSGDVVVCATD ALMTGFTGDFDSVIDCNVAVTQTVDFSLDPTFTIETTTVPQDAVSRSQRRGRTGRGRLGIYRYVSPGE RPSGMFDSVVLCECYDAGCAWYELTPAETTVRLRAYLNTPGLPVCQDHLEFWEGVFTGLTHIDAHFL SQTKQAGENFPYLVAYQATVCARAKAPPPSWDTMWKCLIRLKPTLHGPTPLLYRLGAVQNEVTLTHPI TKYIMTCMSADLEVVT

Consensus sequence NS4A

N- -> C-terminal direction

STWVLVGGVLAALAAYCLSVGSVVIVGRIILSGKPAVIPDREVLYQQFDEMEEC