The present invention is directed to hollow core optical ring resonators (HCORRs), methods of fabricating HCORRs, and methods of using HCORRs in sensing applications. In particular, the evanescent field and whispering gallery modes of the HCORRs may be used to detect a target analyte within the hollow core of the HCORR. Other features of the present invention include utilizing the HCORR as part of a multiplex sensing device, including using the HCORR in capillary electrophoresis and chromatography applications.