Graphene nanoparticles-based ELISA as a crucial new diagnostic tool for diagnosis of human filariasis

Abstract

Background: Filariasis is a disease caused by filarial parasitic worms, which are microscopic roundworms that live in the blood and tissues of humans. Graphene oxide (GO) sheets are excellent nano carriers in many analytical methods. In this study, a modified enzyme-linked immunosorbent assay (ELISA) strategy was developed using antibody-functionalized GO sheets. This modification significantly reduced the limit of detection (LOD) and cost greatly of this assay. Serum samples from infected individuals were collected from different Governorates in Egypt. Methods & Materials: The microfilarial status of the individuals was assessed by membrane filtration followed by visualization under a light microscope Sera were collected after informed consent from 27 microfilaremic patients (MF), 21 with chronic lymphatic disease (CL), and 20 microfilariae negative healthy individuals residing in the nonendemic areas, in parallel sera from 20 other parasites infected patients were collected. All these persons were subjected to the following after their concent; history taking, clinical examination and laboratory investigations which included: examination of blood samples for microfilaria using thick blood film and serological tests for detection of the circulating filarial antigen (CFA) using monoclonal antibody based Og4C3 commercial kit ELISA, classical recommended mapping tool (ICT test) and grapheme nanoparticles-based ELISA Results: None of the 20 non-endemic normal sera were positive for filarial antigen indicating the specificity of commercial kit ELISA. In contrast, 23/27 microfilaraemic sera, 7/21 chronic lymphatic patients sera showed the presence of filarial antigen. Based on ICT 18/27 microfilaraemic sera, 9/21 chronic lymphatic patients sera showed the presence of filarial antigen. Using GO sheets nanoparticles-based ELISA 25//27 microfilaraemic sera, and 6/21 chronic lymphatic patients sera showed the presence of filarial antigen. Conclusion: In conclusion, GO nanoparticle sheets are excellent nano analytical methods using a modified enzyme-linked immunosorbent assay (ELISA) strategy for diagnosis of human filariasis.