How to find a needle in a haystack

Almost every molecule has an individual ‘infrared fingerprint’, i.e. it can be precisely determined by its reaction to IR radiation of different wavelengths: This is very practical for making even the smallest quantities of different substances recognisable, for example in the pharmaceutical industry or in environmental analysis. However, if, for example, an attempt is made to detect impurities in the strongly absorbing solvent water, the detection of H2O molecules is not a problem, but it becomes difficult or even impossible to irradiate the sample with conventional IR light sources in order to get to the molecules that are actually of interest.

This is where the new CD Laboratory for Advanced Mid-lnfrared Laser Spectroscopy in (Bio-)process Analytics at TU Wien comes into play: Head of Laboratory Georg Ramer and his team, supported by the company partners Baxalta Innovations/Takeda, Eralytics and DRS Daylight Solutions, are researching the use of so-called ‘quantum cascade lasers’, which, in comparison to conventional IR light sources, produce up to 1 million more intense IR light, thus enabling it to penetrate even heavily absorbing samples and allowing for wavelength fine-tuning, so that many different substances can be detected with a single laser! In order to enable better algorithms for data evaluation and, in the future, even the detection of individual molecules in samples, the team is working towards a comprehensive understanding of the interaction between the laser and the sample.