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S. Kulka, G. Quintas, B. Lendl:
"On-line capillary electrophoresis FTIR detection for the separation and characterization of proteins";
Vibrational Spectroscopy, 42 (2006), 42; S. 392 - 396.

Capillary electrophoresis (CE) with online FTIR spectroscopic detection was used to sep. a mixt. of three model proteins and to provide information on the dominant secondary structures of the sepd. proteins. Online FTIR transmission measurements were achieved using a micro-machined flow cell made out of CaF2 and SU-8 polymer which was attached to the fused silica capillaries using com. O-rings. The IR beam was focused on the detection window using an off-axis parabolic mirror attached to an external optical port of the spectrometer. As the absorption of water heavily overlaps the so-called amide I band of the proteins the sepns. were carried out in heavy water (D2O). The model proteins studied were myoglobin, a-lactalbumin and b-lactoglobulin having different secondary structures. It could be shown that the performance of the sepn. was comparable to conventional UV-vis detection and that the IR-peak positions of the proteins studied were the same as obtained in ref. measurements using the ATR technique.