A bifunctional immunosensor based on osmium nano-hydrangeas as a catalytic chromogenic and tinctorial signal output for folic acid detection

Abstract

Schematic of the bifunctional immunosensor based on osmium nano-hydrangeas as a catalytic chromogenic and tinctorial signal output for folic acid detection.

Osmium and OsOx nanoparticles: an overview of syntheses and applications

“…A colorimetric sensor was developed for H 2 O 2 detection with improved properties compared to Au or Pt based sensors 87 , see the illustration in Figure 7 . Other examples include glucose and pyruvic acid detections 54 , folic acid detection 88 colorimetric sensors for heavy metal ions discrimination (Cu 2+, Ag + , Cd 2+, Hg 2+, and Pb 2+ ) 89 . Os nanoparticles also show SERS properties 36 , 37 , 76 .…”

Rapid immunoassay for dual-mode detection of HPV16 and HPV18 DNA based on Au@PdPt nanoparticles

“…14–18 However, the sensitivity of traditional LFIA using Au nanoparticles (AuNPs) as visual signals is generally lower than that of LFIA based on other metal nanoparticles. 19,20 Scientists have endeavored to improve the capabilities of LFIA, such as the sensitivity, accuracy and multi-target detection capability, by introducing new materials, technologies and methods. 21–23 In recent years, attention has increasingly been turned to LFIA based on metal nanocomposites, showing promising advantages.…”

Multinanozyme Systems: The New Generation of Nanozymatic Systems

“…Thanks to the significant and characteristic peroxidase-like activity of these nanozymes, the nanoscale peroxidase mimic materials can be utilized for design and development of the innovative catalyst-based analytical sensors which currently known as nanozyme-based sensors [22,23]. Regarding the design and explore of the nanozymatic sensors, up to date, different types of the nanozyme-based sensors have been designed and constructed for the chemi-quantification and bio-quantification of a variety of compounds such as glutathione (GSH) [24][25][26], folic acid [27], xanthine [28], metal cations [29], glucose [30], H2O2 [31,32], and explosives [33], as well as cysteine [34] using the nanozyme-catalyzed/mediated oxidation of the common chromogenic substrates of peroxides enzyme such as 3, 3´, 5, 5´-tetramethylbenzidine (TMB) and o-phenylenediamine (OPD) to their colored cation radicals [22]. Besides the OPD and TMB-based sensing methods, in 2020, Hormozi Jangi et al explored a new type of the colorimetric nanozyme-based sensors by employing the n-electron irreversible oxidation reaction of the high 2 stable 3,3′-diaminobenzidine (DAB) to it's corresponding stable brown-colored indamine polymer and used this resulted indamine polymer as the analytical probe instead of the common cation radicals resulting from TMB and OPD [29].…”