Photonic resonator outcoupler microscopy (PROM)

Photonic Resonator Outcoupler Microscopy (PROM) is a novel, label-free approach for dynamic, long-term, quantitative imaging of a sample on a surface of a photonic crystal (PC) biosensor, in which components of the sample outcouple photons from the resonant evanescent field, resulting in highly localized reductions of the reflected light intensity. By mapping changes in the resonant reflected peak intensity from the PC surface, components of a sample (e.g., focal adhesions) can be detected and dynamically tracked. To demonstrate the simplicity and utility of PROM for focal adhesion imaging, PROM images are compared with biosensor images of surface-bound dielectric permittivity and with fluorescence microscopy images of labeled adhesion molecules in dental stem cells. PROM can dynamically quantify the surface-attached cellular mass density and lateral dimensions of focal adhesion clusters.