Biosensing by in situ infrared spectroscopy

Michio Niwano, Ayumi Hirano-Iwata

Research output: Contribution to journalReview articlepeer-review


We are investigating reactions at Si surfaces and interfaces using infrared spectroscopy in the multiple internal reflection geometry (MIR-IRAS). This technique, in which infrared light beams penetrate a Si crystal wafer internally while reflecting many times, enables us to monitor surface reactions with a quite high surface sensitivity. Since Si surfaces can be observed from inside, we can monitor chemical processes at Si surfaces under various environments. In this review, our MIR-IRAS approaches for the label-free detection of biomolecular interactions are presented. In our MIR-IRAS method, by analyzing IR absorption signals we can detect any structural changes induced by the biomolecular interactions. MIR-IRAS is applicable to in situ real-time monitoring of versatile samples including DNA, proteins, and living cells, regardless of the molecular size and state of the samples.

Original languageEnglish
Pages (from-to)793-800
Number of pages8
JournalBunseki Kagaku
Issue number11
Publication statusPublished - 2015 Dec 9


  • Biomolecular interaction
  • Infrared spectroscopy (IRAS)
  • Label-free detection
  • Multiple internal reflection
  • Si surface


Dive into the research topics of 'Biosensing by in situ infrared spectroscopy'. Together they form a unique fingerprint.

Cite this