Here is a comment on the article cited by Mandal: http://www.novuslight.com/painless-blood-glucose-monitoring-with-photoacoustic-spectroscopy_N1819.html

Here is another effort: http://www.lss.ethz.ch/research/projects/glucose

That is very good information, Subhamoy and Ernesto. Use of mid-IR instrad of NIR has always been a laboratory reality, but producing a small portable system is very difficult so far. Advances in lasers is giving hope that it can be a viable approach in the near future. Thanks!