Future immunoassays and nucleic acid hybridization assays will be performed in miniaturized formats that utilize microchips or microparticles. This will require a sensitive detection technology that allows spatial resolution. By using fluorescent europium chelates and time-resolved microfluorometry, one can detect 11 000 europium molecules on individual microparticles. In a miniaturized noncompetitive immunoassay of prostate-specific antigen (PSA), we quantitatively detected 5 ng/L (0.05 amol per particle) of the analyte on an individual microparticle with excellent precision over the whole measurement range (CV <10%). Using a hybridization assay, we also could detect the ΔF508 mutation for cystic fibrosis on individual microparticles. Consequently, fluorescent lanthanide chelate labels and time-resolved microfluorometry qualify as the next generation of technology in this field.
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.