Lab-on-chip system combining a microfluidic-ELISA with an array of amorphous silicon photosensors for the detection of celiac disease epitopes

Abstract

This work presents a lab-on-chip system, which combines a glass-polydimethilsiloxane microfluidic network and an array of amorphous silicon photosensors for the diagnosis and follow-up of Celiac disease. The microfluidic chip implements an on-chip enzyme-linked immunosorbent assay (ELISA), relying on a sandwich immunoassay between antibodies against gliadin peptides (GPs) and a secondary antibody marked with horseradish peroxi- dase (Ig-HRP). This enzyme catalyzes a chemiluminescent reaction, whose light intensity is detected by the amorphous silicon photosensors and transduced into an electrical signal that can be processed to recognize the presence of antibodies against GPs in the serum of people affected by Celiac syndrome.\ud The correct operation of the developed lab-on-chip has been demonstrated using rabbit serum in the microfluidic ELISA. In particular, optimizing the dilution factors of both sera and Ig-HRP samples in the flowing solutions, the specific and non-specific antibodies against GPs can be successfully distinguished, showing the suitability of the presented device to effectively screen celiac disease epitopes

Thin Film Differential Photosensor for Reduction of Temperature Effects in Lab-on-Chip Applications

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“…To minimize the electromagnetic noise the measurements were performed in a Faraday cage. In practical LoC applications, the reduction of noise can be attained including the system in a small metal case as the one reported in [ 18 ].…”

Anti-p53 Autoantibody Detection in Automatic Glass Capillary Immunoassay Platform for Screening of Oral Cavity Squamous Cell Carcinoma

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