Development of a Pioneering Electrochemical Immunosensor for Accurate Detection of Human Visceral Leishmaniasis with Purified Leishmania spp. Recombinant Antigen

Abstract

Leishmaniasis is a disease that affects a large part of the population of Latin America, especially in Brazil. It has a high mortality rate if left untreated. The main diagnostic methods currently used are based on signs and symptoms suggestive associated with parasitological and/or immunological tests, however, such tests have disadvantages such as low sensitivity and specificity, high cost, need for equipped laboratories and qualified professionals. Thus, it is necessary to have a fast, accurate, low-cost, portable diagnosis that has good sensitivity and specificity. In this study, a recombinant antigen (Ag) called DTL-4 was used because of its potential to improve the sensitivity and specificity of the tests because it only allows specific binding with the antibody in the serum of patients with the disease. The results of the proposed immunosensor showed an estimated detection limit of 0.0442 ng mL−1. The absence of modifications with gold nanoparticles is another interesting point when we compare the cost related to the biosensor in question with other diagnostic methods. Thus, the proposed immunosensor has low cost, high specificity and sensitivity. In this way, the biosensor in question shows promise for validating the diagnostic platform and its future portable use in public health.