Infrared spectral range between 1.7 and 2.5 ?m is of particular interest for biomedical sensing applications due to the presence of first overtone C-H stretch and a combination of stretch and bending vibrations of C-H, N-H, and O-H bonds. These vibrations are molecule specific and can be used to selectively sense important biomolecules such as glucose, lactate, urea, ammonia, serum albumin, etc. In this paper, we review recent developments of swept-wavelength lasers based on GaSb type-I gain-chip technology, their key performance parameters for spectroscopy applications and provide experimental data on spectroscopic sensing of the key biomolecules both in synthetic solutions as well as whole blood.
IEEE Journal of Selected Topics in Quantum Electronics, vol. 25 (6), pp. 1-12