A sensing and analysis system on a chip for sensing and analyzing chemical or biological analytes includes a chromatography column having an inlet and an outlet formed on the chip for temporal separation of components of analytes and at least one whispering gallery mode (WGM) optical resonator for sensing of the components. The chromatography column is formed on a first wafer layer. Each WGM optical resonator includes a hollow sealed enclosure formed at or over the inlet or the outlet of or elsewhere along the chromatography column such that a gas flowing through the chromatography column fills the hollow sealed enclosure. Each WGM optical resonator further includes an optical waveguide aligned with the sealed hollow enclosure for evanescent wave light coupling.