Photonic Crystal Microscope Quickly Detects Biomarkers for P-O-C Diagnostics

A compact photonic resonator absorption microscopy (PRAM) instrument, developed by a team at the University of Illinois Urbana-Champaign, provides fast, selective detection of cancer biomarkers for diagnostics at the point of care. The instrument takes advantage of the optical coupling between plasmonic gold nanoparticle tags and a photonic crystal surface to provide the contrast users need to observe and count gold nanoparticles that are linked to proteins or other biomarkers. By matching the resonant wavelength of the photonic crystal to the wavelength of the gold nanoparticle’s surface plasmon, the microscope generates strong, localized quenching of the photonic crystal’s resonant reflection intensity. This allows...