Tethered Catalytic Hairpin Assembly with Plasmon-Enhanced Fluorescence Readout for Single Molecule Detection.

ABSTRACT: Here a novel digital bioassay readout concept is reported that does not rely on enzymatic amplification nor compartmenting of an analyzed liquid sample. Rather, it is based on counting individual affinity-captured target biomolecules via the use of a tethered catalytic hairpin assembly (tCHA) deployed on a solid sensor surface with spatial confinement utilized by a flexible polymer linker (FPL). Wide-field plasmon-enhanced fluorescence (PEF) imaging is employed for optical real-time probing of the reaction kinetics, where affinity-captured target molecules are manifested as spatially distinct bright fluorescent spots. The effect of the length of the FPLs is investigated, and the analytical performance of the dual amplification tCHA-PEF concept is tested by using a model short single-strand

SUBMITTER: Asai N 

PROVIDER: S-EPMC12391651 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature