EpCAM determination in peripheral blood samples using a microfluidic immunosensor based in silver nanoparticles as platform

FRANCISCO ORTEGA SÁNCHEZ; JOSÉ A. LORENTE; MARTÍN A. FERNÁNDEZ BALDO; JULIO RABA; MARÍA JOSÉ SERRANO

Granada

Simposio; International Symposium Precision Medicine Based on Liquid Biopsies from Detection to Dissection; 2016

CENTRO PFIZER ? JUNTA DE ANDALUCÍA ? CENTRO DE GENÓMICA E INVESTIGACIÓN ONCOLÓGICA (GENYO), UNIVERSIDAD DE GRANADA

EpCAM determination in peripheral blood samples using a microfluidic immunosensor based in silver nanoparticles as platformOrtega Sánchez Francisco Gabriel 1, Fernández Baldo Martín 2, Serrano Fernández María José 1, Lorente José Antonio 1, Raba Julio 2. Email: jraba@unsl.edu.ar1 GENYO. Centre for Genomics and Oncological Research: Pfizer / University of Granada / Andalusian Regional Government. PTS Granada, Avenida de Ilustración, 114 18016 Granada, Spain.2 INQUISAL, Departamento de Química. Universidad Nacional de San Luis, CONICET. Chacabuco 917. D5700BWS. San Luis, Argentina.In the present work, we report a microfluidic immunosensor for epithelial cancer biomarker EpCAM (epithelial cell adhesion molecule) determination. It is based on the use of synthetized silver nanoparticles (AgNPs) covered by chitosan (Cts). AgNPs-Cts were covalently attached to the central channel (CC) of the microfluidic immunosensor. These nanoparticles were employed as platform for anti-EpCAM monoclonal antibodies immobilization for specifically recognize and capture EpCAM in peripheral blood samples. Afterwards, the amount of this trapped epithelial cancer biomarker was quantified by HRP-conjugated anti-EpCAM-antibody. HRP reacted with its enzymatic substrate in a redox process which resulted in the appearance of a current whose magnitude was directly proportional to the level of EpCAM in the peripheral blood sample. The structure and morphology of synthetized AgNPs-Cts were characterized by UV-visible spectroscopy, scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). The calculated detection limits for microfluidic immunosensor and the commercial ELISA were 2.7 and 13.9 pg mL-1, respectively and the within- and between-assay coefficients of variation were below 6.37% for the proposed method. The microfluidic immunosensor is simple, sensitive, specific and reproducible. It has the potential for reliable point-of-care clinical diagnosis and prognosis of epithelial origin tumors in biological samples.