CONICET | Buscador de Institutos y Recursos Humanos

In the present article, a novel microfluidic immunosensor coupled with electrochemical detection for anti-gliadin IgG antibodies quantification is proposed. This device represents an important tool for a fast, simple, sensitive and automated diagnostic of the celiac disease, which is carried out, through detection of anti-gliadin IgG antibodies present in human serum samples. The celiac disease (CD) is an autoimmune disease generated by gluten proteins fractions called prolamins. This pathology affects about one in 250 people around of world, produces intestinal inflammation, villous atrophy and crypt hyperplasia, which cause a range of symptoms including altered bowel habits, malnutrition and weight loss. Our immunosensor consists in a pexiglas device coupled to a gold electrode, with a central channel containing 3-aminopropyl-modified controlled-pore glass (AP-CPG). The quantification of anti-gliadin IgG antibodies was carried out using a heterogeneous, non-competitive enzyme-linked immunosorbent assay (ELISA) in which, IgG antibodies bounded to gliadin protein, immobilized on AP-CPG, were determinated by alkaline phosphatase (AP) enzyme-labeled second antibodies specific to human IgG. The p-Aminophenyl phosphate (p-APP) was converted to p-aminophenol (p-AP) by AP, and the electroactive product was quantified on gold electrode at 0.250V. The calculated detection limits for electrochemical detection and the ELISA procedure were 0.52 and 2.72 URmL-1, respectively, and the within- and between-assay coefficients of variation were below 5.8%. The optimized procedure was applied to the determination of anti-gliadin IgG antibodies in human serum samples.