Iridium oxide (IV) nanoparticle-based lateral flow immunoassay

Abstract

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 colour gives a high contrast against the white background of the strips being in this way excellent labels.

Integrating high-performing electrochemical transducers in lateral flow assay

“…In addition, background signal in electrochemical detection is considerably lower due to the uncharged backbone. Thus, monitoring the hybridization event of PNA with DNA or RNA based on electrochemical label-free techniques is feasible as demonstrated in previous studies where charge of the probe plays an important role for signal generation [48,50,51]. LFA combined with PNA probes has been successfully implemented to determine micro-RNA-150 in plasma samples for preterm birth screening test [52].…”

“…Further improvements focused on tracer strategies, like metal ligand complexes [17], cellulose nanobeads [18], and the coupling to a smartphone [19]. In the past few years, the research has been focused on further developing labels like Ptnanoparticles (PtNP) [20], the use of Ag staining for amplification [21], combining LFA with SERS [22], implementing nanofibers (NF) [23], using different shapes of colloidal gold [24], using different nanoparticles (NP) like IrO 2 [25] or CuO [26], and integrating electrodes for electrochemiluminescence (ECL) [27]. The texts shown in blue, green, purple, and red represent the development focusing on assay format, signal tracer, detection technique, and recognition element, respectively.…”

Rapid point‐of‐care testing methods/devices for meat species identification: A review

“…This is possible because of detection tags that accumulate and give color at T‐ and C‐lines. These tags include colloidal carbon, QDs, fluorescent probes, phosphors, AuNPs, silver NPs, selenium NPs, bioluminescent molecules, enzymes, iridium oxide (IV) NPs, and magnetic particles (Chen, Fu, Xie, Wang, & Tang, 2019; Huang, Aguilar, Xu, Lai, & Xiong, 2016; Quesada‐González et al., 2019; Wang, Xiao, et al., 2019; Zhang, Belwal, et al., 2020; Znoyko, Orlov, Bragina, Nikitin, & Nikitin, 2020). AuNPs (colloidal gold) are mostly used in LFA devices due to (a) ease of production, (b) low cost, (c) optical properties, and (d) higher stability (Morbioli, Mazzu‐Nascimento, Stockton, & Carrilho, 2017).…”

Nickel Hydroxide Nanoparticles for Application in Immunochromatographic Strip Tests of Melamine

“…Applications of metal nanoparticles as probes or labels in analytical methods have attracted great attention owing to their similar dimensions to biomolecules, such as enzymes, particularly for immunochromatographic strip tests, which combine an immunoreaction with a chromatographic technique, for protein analysis and clinical diagnosis. (4)(5)(6)(7)(8)(9) Meanwhile, gold nanoparticles are the most popular metal nanoparticles applied in immunochromatographic strip tests owing to their distinctive red color and good affinity to proteins. (5) However, although gold nanoparticles possess excellent biocompatibility and stability, they are relatively expensive compared with other common metals such as nickel.…”