title: High-Throughput Electrochemical Microfluidic Immunoarray for Multiplexed Detection of Cancer Biomarker Proteins.
abstract: Microchip-based microfluidic electrochemical arrays hold great promise for fast, high-throughput multiplexed detection of cancer biomarker proteins at low cost per assay using relatively simple instrumentation. Here we describe an inexpensive high-throughput electrochemical array featuring 32 individually addressable microelectrodes that is further multiplexed with an 8-port manifold to provide 256 sensors. The gold electrode arrays were fabricated by wet-etching commercial gold compact discs (CD-R) followed by patterned insulation. A print-and-peel method was used to create sub-microliter hydrophobic wells surrounding each sensor to eliminate cross contamination during immobilization of capture antibodies. High-throughput analyses were realized using eight 32-sensor immunoarrays connected to the miniaturized 8-port manifold, allowing 256 measurements in <1 h. This system was used to determine prostate cancer biomarker proteins prostate specific antigen (PSA), prostate specific membrane antigen (PSMA), interleukin-6 (IL-6), and platelet factor-4 (PF-4) in serum. Clinically relevant detection limits (0.05 to 2 pg mL-1) and 5-decade dynamic ranges (sub pg mL-1to well above ng mL-1) were achieved for these proteins utilizing precapture of analyte proteins on magnetic nanoparticles decorated with enzyme labels and antibodies.
authors.affiliation: Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States.
authors.forename: Chi K
authors.initials: CK
authors.lastname: Tang
authors.affiliation: Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States.
authors.forename: Abhay
authors.initials: A
authors.lastname: Vaze
authors.affiliation: Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States.
authors.forename: Min
authors.initials: M
authors.lastname: Shen
authors.affiliation: Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States; Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269, United States; Department of Surgery and Neag Cancer Center, University of Connecticut Health Center, Farmington, Connecticut 06032, United States; School of Chemistry, National University of Ireland at Galway, Galway, Ireland.
authors.forename: James F
authors.initials: JF
authors.lastname: Rusling
keywords: cancer biomarkers proteins; electrochemical array; high-throughput; immunosensors; sensor fabrication