Polymer microring resonators for biochemical sensing applications

TLDR

Microring resonators fabricated by direct imprinting exhibit high Q factors (~20,000) and enable detection and quantification of biomolecules in both homogeneous solutions and surface‑bound configurations. Polymer microring resonators were demonstrated for label‑free sensing of biomolecules, achieving a detection limit of 10⁻⁷ RIU in homogeneous sensing, ~250 pg mm⁻² on the surface, and capable of detecting both small and large biomolecules.

Abstract

Polymer microring resonators were demonstrated for sensing biomolecules without using fluorescent labels. The microring devices, fabricated by a direct imprinting technique, possess high Q factors of /spl sim/20000. This feature provides high sensitivity and a low detection limit for biochemical sensing applications. With these properties, the devices were used to detect and quantify the biomolecules present either in a homogeneous solution that surrounds the microring waveguide (homogeneous sensing) or specifically bound on the waveguide surface (surface sensing). In the former sensing mechanism, the current devices can detect an effective index change of 10/sup -7/ refractive index units (RIU); in the latter, they can reach a detection limit of /spl sim/250 pg/mm/sup 2/ of biomolecular coverage on the microring surface. In addition, the experiments show that the devices can detect both small and large biomolecules.