Mid-IR quantum cascade lasers as an enabling technology for analytical chemistry

KRISTAMENT, C.; BRANDSTETTER, M.; SCHWAIGHOFER, A.; ALCARAZ, M.R.; LENDL, B.

CLEO: Science and Innovations, CLEO-SI 2015

Optical Society of America (OSA)

Lugar: San Jose; Año: 2015 p. 1 - 2

After providing an overview on the state-of-the-art of measuring condensed phase samples by quantum cascade lasers (QCL), this presentation will focus on protein analysis. The qualitative analysis of mid-IR spectra of aqueous protein solutions provides information on the secondary structure elements present in the proteins under study. In this work an external cavity (EC)-QCL was used for performing transmission measurements of different aqueous protein solutions in a CaF2 flow cell with optical paths up to 75 μm. The strong temperature dependence of the ν2-band of water overlapping the amide I absorption band (~1650 cm-1) required a temperature stability of +/-0.005°C. Successful determination of the secondary structures of albumin and β-lacto-globulin was achieved in the low g/L concentration range. © OSA 2015.