A gold nanoparticle piezoelectric immunosensor using a recombinant antigen for detecting Leishmania infantum antibodies in canine serum

• Published in: Biochemical engineering journal 2016-06, Vol.110, p.43-50
• Main Authors: Ramos-Jesus, Joilson, Pontes-de-Carvalho, Lain Carlos, Melo, Stella M. Barrouin, Alcântara-Neves, Neuza M., Dutra, Rosa F.
• Format: Article
• Language: English
• Subjects: Immunosensor; Leishmania infantum; Leishmaniasis; Quartz crystal microbalance
• ISSN: 1369-703X; 1873-295X
• DOI: 10.1016/j.bej.2016.01.027

[Display omitted] •An immunoelectrode for Leishmania infantum antibodies in canine serum based AuNP-nafion film was developed.•AuNP cysteamine modified allowed a covalent immobilization by carboxyl groups of the recombinant antigen.•t was possible detect L. infantum antibodies in canine serum in clinical range for adequate diagnosis. Visceral leishmaniasis (VL) is a severe systemic and infectious disease potentially fatal when undiagnosed or untreated. So far, accurate diagnosis is still a problem, especially in endemic areas and in the tracking and screening of asymptomatic dogs, which are good reservoirs and main host in urban areas. Recombinant antigens based on DNA technology have provided more reliable serological diagnostics since the specificity can be achieved easier than using whole extracts. This work reports a sensitive piezeolectric immunosensor for anti-Leishamnia antibodies based on rLci2B recombinant antigens immobilized on quartz crystal electrode. The electrode surface was assembled by a nafion film recovered by gold nanoparticles (AuNPs) to promote a greater amount of rLci2B due to the increase of surface area and stability on bonds. The immunosensor distinguished the positive VL canine serum showing a good linearity (r=0.989; p