Nanoassay development

National Heart, Lung, And Blood Institute

Investigators

Linked publications, trials & patents

Abstract

Fluorescence Spectroscopy is inherently a very sensitive technique; it already forms the basis of most non-radioactive real time assays like PCR. Our lab previously collaborated with former fellows (now in biotech industry) to develop alternatives to PCR like "CataCleave" probes for SNPs. We continue to study the photophysics and proper coupling of DNA components to carriers such as multilayer metal nanoparticles for much faster PCR analysis and the use of FCS (see MPM report) to quantify very tight protein-protein and protein-DNA binding in sub-microliter drops (analytes are present in sub-femtomole amounts). We temporarily suspended (this year) doing MPM-FCS and Time-Resolved Fluorescence together; in previous years, we had numerically combined time-resolved fluorescence detection with translational mobility (FCS) to help identify "free" and "bound" signatures for assay. We are presently designing STAQ probes (see nanoscopy project) for DNA/RNA probing, analagous to catacleave, in plans to only superresolve tight binding sites. Recently we have used TCSPC to begin untangling designed aptamer heterogeneity questions (see MPM project and TR project). Aptamers can combine their turn-on fluorescence with analyte detection, so we have begun developing O2-sensing concepts for RNA. We also continued to study the signatures for peptide and DNA "Excitonic" probes that self-quench unless unfolded or cleaved, in collaboration with local industry and most recently in aptamer collaborations using dual thiazole probes.. Collaborative efforts have been unfortunately inhibited by limited on-site presence.