Iridium oxide (IV) nanoparticle-based lateral flow immunoassay

Lateral flow biosensors are paper-based devices that allow the detection of different types of analytes with quickness, robustness and selectivity, without leaving behind paper sensors benefits as low-cost, recyclability and sustainability. Nanomaterials have been widely reported in lateral flow biosensors, offering new sensing strategies based on optical or electrical detection techniques. Looking for other advantageous nanomaterials, we propose for the first time the use of iridium oxide (IV) nanoparticles in lateral flow assays for the detection of human immunoglobulin as a model protein. These nanoparticles can be easily prepared and conjugated with biomarkers. Their dark blue color gives a high contrast against the white background of the strips being in this way excellent labels.
We acknowledge support from MINECO (Spain) MAT2017-87202-P and project PCIN-2016-066 (program Euronanomed 2). This work is also funded by the CERCA Programme / Generalitat de Catalunya. ICN2 is supported by the Severo Ochoa program from Spanish MINECO (Grant No. SEV-2017-0706). Daniel Quesada-González and Amadeo Sena-Torralba acknowledge Autonomous University of Barcelona (UAB) for the possibility of performing this work inside the framework of Chemistry and Biotechnology Ph.D. Programmes, respectively.