Screening for cystic fibrosis via a magnetic and microfluidic immunoassay format with electrochemical detection using a copper nanoparticle-modified gold electrode

MARÍA LUZ SCALA BENUZZI; SIRLEY V. PEREIRA; JULIO RABA; GERMÁN ALEJANDRO MESSINA

MIKROCHIMICA ACTA

SPRINGER WIEN

Lugar: Viena; Año: 2015 vol. 183 p. 397 - 405

0026-3672

This article describes a microfluidic electrochemicalimmunoassay that features two strategies, viz. (a), the incorporationof magnetic nanoparticles (MNPs) into the centralmicrofluidic channel and acting as a bioaffinity support for theimmobilization of the antibody against the immunoreactivetrypsin (anti-IRT), and (b), the electrodeposition of coppernanoparticles (CuNPs) on a gold electrode. IRT, a marker forcystic fibrosis, is extracted from blood samples onto a diskusing ultrasonication, eluted, and then injected into the detectionsystem where it is captured by anti-IRT-loaded nanoparticles(anti-IRT-Ab-MNPs). Bound IRT is electrochemicallyquantified after addition of HRP-labeled anti-IRT-Ab which,in the presence of H2O2, catalyzes the oxidation of catechol toform o-benzoquinone which is detected at a working potentialof −150 mV (vs. Ag/AgCl). The electrochemical response tobenzoquinone is proportional to the concentration of IRT inthe range from 0 to 580 ng⋅mL−1. The coefficients of variationare