Anti-Tissue-Transglutaminase IgA Antibodies Presence Determination Using Electrochemical Square Wave Voltammetry and Modified Electrodes Based on Polypyrrole and Quantum Dots

Abstract

A novel electrochemical detection method utilizing a cost-effective hybrid-modified electrode has been established. A glassy carbon (GC) modified electrode was tested for its ability to measure electrochemical tTG antibody levels, which are essential for diagnosing and monitoring Celiac disease (CD). Tissue transglutaminase protein biomolecules are immobilized on a quantum dots-polypyrrole nanocomposite in the improved electrode. Initial, quantum dots (QDs) were obtained from Bombyx mori silk fibroin and embedded in polypyrrole film. Using carbodiimide coupling, a polyamidoamine (PAMAM) dendrimer was linked with GQDs-polypyrrole film to improve sensor sensitivity. The tissue transglutaminase (tTG) antigen was cross-linked onto PAMAM using N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC)-N-hydroxy succinimide (NHS) chemistry to develop a nanoprobe that can detect human serum anti-tTG antibodies. The physicochemical characteristics of the synthesized nanocomposite were examined by FTIR, UV-visible, FE-SEM, EDX, and electrochemical studies. The novel electrode measures anti-tissue antibody levels in real time using human blood serum samples. The modified electrode has great repeatability and an 8.7 U/mL detection limit. Serum samples from healthy people and CD patients were compared to standard ELISA kit assays. SPSS and Excel were used for statistical analysis. The improved electrode and detection system can identify anti-tissue antibodies up to 80 U/mL.

Keywords

• silk fibroin
• quantum dots
• polypyrrole
• electroanalysis
• anti-tTG antibody