Multiple internal reflection photonic lab on a chip

Andreu Llobera, Ralph Wilke, Stefanie Demming, Stephanus Büttgenbach, Victor Javier Cadarso, César Fernández-Sánchez

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review


In this work it is shown how the inclusion of the air mirrors allows the implementation of a highly sensitive absorbance based biosensor based on Multiple Internal Reflection (MIR). They have been fabricated in a single-mask step and replicated in Poly(dimethylsiloxane) (PDMS) using soft lithographic techniques. Experimental results confirm the raytracing predictions: if the air mirror is accurately defined, the propagating light matches the conditions of Total Internal Reflection (TIR) at the PDMS-air interface, which results in a complete reflection of the light towards the system. Additionally, the shape of the air mirrors can be modified so as to allow the light focusing at concrete places. With the recursive positioning of air mirrors, the optical path length has been meaningfully lengthened without a dramatic increase of the volume. The experimental results also matches with the ray tracing predictions and allows obtaining a LOD of 110 nM. The results are auspicious for the implementation of the absorbance-based photonic lab on a chip systems.

Original languageEnglish
Title of host publicationISOT 2009 - International Symposium on Optomechatronic Technologies
Number of pages5
Publication statusPublished - 2009
Externally publishedYes
EventISOT 2009 - International Symposium on Optomechatronic Technologies - Istanbul, Türkiye
Duration: 21 Sept 200923 Sept 2009


ConferenceISOT 2009 - International Symposium on Optomechatronic Technologies


  • Biosensor
  • Photonic lab on a chip
  • Polydimethylsiloxane (PDMS)

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