Impedimetric immunosensing in a porous volumetric microfluidic detector

SENSORS AND ACTUATORS B-CHEMICAL

卷:234

Article

Wiederoder, Michael S.¹  Misri, Isaac²  DeVoe, Don L.^1,2 

[1] Univ Maryland, Fischell Dept Bioengn, College Pk, MD 20742 USA

[2] Univ Maryland, Dept Mech Engn, College Pk, MD 20742 USA

关键词: Impedance sensing;    Conductometric;    Immunoassay;    Nanoparticles;    Silver enhancement;   

DOI  :  10.1016/j.snb.2016.05.015

来源: Elsevier

【 摘 要 】

A sensitive and rapid impedemetric immunosensor is demonstrated utilizing porous volumetric microfluidic detection elements and silver enhanced gold nanoparticle probes. The porous detection elements significantly increase capture probe density and decrease diffusion length scales compared to conventional planar sensors to improve target capture efficiency and enhance impedance signal. In this work, a packed bed of silica beads functionalized with antibody probes serves as a porous sensor element within a thermoplastic microchannel, with an interdigitated gold electrode microarray used to measure impedance changes caused by the concentration dependent formation of silver aggregates. The measured impedance change is independent of electrode spacing, enabling a device with low resolution electrodes to achieve a sandwich immunoassay detection limit between 1 and 10 ng/mL with a 4-log dynamic range, with a total assay time of 75 min. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

Free