Ultra-stable silver nanoplates: efficient and versatile colorimetric reporters for dipstick assays

Abstract

Noble metal anisotropic nanostructures, such as silver nanoplates (AgNPls), are interesting because they possess enhanced plasmonic properties compared to their spherical counterparts: increased extinction coefficient and tunable maximum of absorption...

Development of a peptide-based lateral flow assay for the detection of the cancer biomarker Mdm2

“…However, the contrast with the NC membrane was not optimal for a naked-eye detection, as underlined in previous studies. 28 On the contrary, the dark blue color provided by the AgNPls led to an excellent contrast and a line could still be observed at a 2 nM concentration of the target protein (see Fig. 3A for the p14–BSA system and Fig.…”

“…We recently demonstrated the high stability of AgNPls coated with calix[4]arenes bearing four carboxyl groups and their huge potential as colorimetric reporters. 28 The coating can be readily obtained through the irreversible reduction of calix[4]arene-tetradiazonium salts, 29,30 resulting in a robust and thin organic monolayer (typically around 2 nm in thickness). 31,32 By selecting silver nanostructures with a blue color, which provides excellent contrast with the assay membrane, we could for example increase 20 times the sensitivity of a LFA intended to detect anti-SARS-CoV-2 IgG in human plasma compared to gold nanoparticles.…”

Tailored Ultrastable Core–Shell Au@Ag Nanoparticles for Enhanced Colorimetric Detection in Lateral Flow Assays

“…Finally, the different types of core−shell NPs used in this study form a library of colorimetric reporters with distinct optical properties. Compared to the silver nanoplates (AgNPls) we previously reported, 18 this strategy allows to increase significantly the extinction coefficient while maintaining the absorption band in the visible region. Such a library paves the way for the development of multiplexed detection systems capable of targeting multiple proteins simultaneously, thereby enhancing diagnostic reliability.…”

“…17 Our research group recently demonstrated that the reductive grafting of calix [4]arene tetradiazonium salts can significantly enhance the stability of both silver nanospheres and nanoplates. 18,19 These preorganized macrocyclic platforms can be strongly anchored onto surfaces by reducing their four diazonium groups into highly reactive radicals, forming ultrastable and densely packed thin layers of calix [4]arenes. 20−22 Additionally, the subsequent covalent attachment of biomolecules (e.g., proteins) onto the calix [4]arene-based layer can be easily achieved through classical bioconjugation reactions with the appending functional arms present on the small rim of the calix [4]arenes.…”

A Protease-Responsive Polymer/Peptide Conjugate and Reversible Assembly of Silver Clusters for the Detection of Porphyromonas gingivalis Enzymatic Activity

“…Herein, we sought to extend this sensing mechanism to silver nanoparticles (AgNPs) because their extinction coefficient is 1 order of magnitude higher than that of AuNPs at equal size; thus, fewer AgNPs are needed to generate the same colorimetric signal which improves the sensitivity of the detection. , AgNPs are also much more sensitive to oxidation than AuNPs, making their handling more challenging because they dissolve and degrade more easily. − Although engineered surface modifications have been reported in the literature to protect the AgNPs, ,, they are still rarely used for in vitro diagnostics.…”