Development of an electrochemical nano-biosensor for rapid and sensitive diagnosis of bilharzia in Kenya

Abstract

Bilharzia, also known as schistosomiasis, is still affecting more than 250 million people, killing about 200 000 annually and leaving millions of others debilitated. Current diagnostic tools have extremely low validity and are not readily applicable for rapid diagnosis in rural and remote areas. In low-grade infections, microscopy, the most commonly used method, may have low sensitivity. For example, in suspected cases, up to five real sample specimens are recommended for increased sensitivity. The rise of nanotechnology has created the potential to significantly improve the current diagnostic approaches. Conjugating antibodies with nanoparticles pools the distinctive properties of the nanoparticles with the specificity and selectivity of the antibodies in the recognition of the antigen. This in return leads to a very versatile and specific mixed product with improved analytical
signal which is important for fast, sensitive and real-time point-of-care diagnosis. In this work, we report the use of nanotechnology to develop a simple and sensitive nano-biosensor which consisted of a nano-strip with immobilized gold nanoparticles conjugated with bilharzia antibody, and demonstrated its potential for diagnosis of bilharzia antigen. A detection range of 1.13 × 10¹ ng mL^–1 to 2.3 × 10³ ng mL^–1 of bilharzia antigen in stool samples and with a limit of detection of 8.3887 × 10^–2 ngmL^–1 was attained, indicating the potential of the nano-biosensor to be used to detect bilharzia antigen in stool samples.

Keywords: Bilharzia, nanobased-biosensor, nanostrips, nanokits