A V-trench biosensor is a sensitive biosensing platform utilizing fluorescence enhancement induced by surface plasmon resonance (SPR). Instruments for the SPR-assisted fluorescence assays, which were complicated and bulky, are drastically simplified and miniaturized by employing sensor chips equipped with prism-integrated microfluidic channels. In this review, the working principle, sensor design, and examples of virus detection of the V-trench biosensor are presented.

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