Nitrogen, phosphorus and oxygen tri-doped porous graphite carbon@oxidized carbon cloth electrodes exhibit excellent activity and durability for full water splitting at all pH values.
Electrochemiluminescence (ECL) has emerged as one of the most important methods for in vitro diagnosis and detection, but it is still limited in sensitivity for ultrasensitive biodetections. Fast and ultrasensitive detection of biomolecules is critical, especially for the clinical detection of cardiac troponin I (cTnI) for cardiac infarction diagnosis. In this study, an effective tactic was developed to enhance ECL efficiency of the luminol system, by combined use of Co 2+ -based metal organic frameworks (MOF), zeolitic imidazolate frameworks (ZIF-67), and luminolcapped Ag nanoparticles (luminol-AgNPs). The integration leads to a pronounced ∼115-fold enhancement in luminol ECL. On the basis of this fascinating sensing platform, a robust label-free ECL immunosensor was constructed for ultrasensitive detection of cTnI, the main marker of myocardial infarction, with good stability and a detection limit as low as 0.58 fg mL −1 (S/N = 3).
Summary
Enhancing electrochemiluminescence (ECL) with plasmonic materials is promising but still a long-standing barrier to improve its sensitivity for ultrasensitive bioassays, due to the lack of comprehensive understanding and effective strategies to fully utilize plasmonic effects for ECL enhancement. Herein, by insulating gold nanoparticles with silica shells (Au@SiO
2
NPs), and finely tuning their core/shell sizes and controlling interparticle spacing via assembling them into a dense nanomembrane, we develop a novel 2D metasurface. Due to well-controlled high density “hot spots” and 2D ordered arrangement of the unit NPs in the nanomembrane, the metasurfaced ECL electrode shows over 1,000-fold plasmonic ECL enhancement for the classical Ru(bpy)
3
2+
-tripropylamine system, which is two orders of magnitude higher than ever reported (<30-fold). Such fabricated ECL biosensor demonstrates superior detection performance for prostate-specific antigen with a detection limit of 3 fg mL
−1
. Our results provide understanding of plasmonic effects for ECL enhancement and will benefit for biosensor construction for ultrasensitive bioassays.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.