A label-free detection method is developed for biosensors and for microfluidic applications. Multiple optical modes, including a conventional surface plasmon resonance (SPR) mode and many bulk modes, are created in a microfluidic channel with metallic coatings on top and bottom. The bulk modes are bulk sensitive and detect analytes in the channel with 20 times higher sensitivity than the SPR, which is particularly suitable for microfluidic devices. The method can be operated either in the SPR mode for detection of molecular binding on a surface or in one of the bulk optical modes for monitoring analytes in the channel.

Original languageEnglish (US)
Article number133901
JournalApplied Physics Letters
Issue number13
StatePublished - Apr 10 2008


ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

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