Conference Agenda

Advances in Instrumental Analytical Chemistry are often linked to technological developments in neighboring disciplines. This is the case with respect to recent advances in mid-IR quantum cascade lasers (QCLs) which are increasingly used as light sources in mid-IR spectroscopy. QCLs offer high spectral power densities, fast amplitude and frequency modulation possibilities, polarized and coherent radiation. Based on these properties a range of new sensing schemes can be developed. In photothermal spectroscopy adsorption induced heating takes place leading to physical changes in the sample matrix. For gas sensing we observe small changes of the sample´s refractive index which can be measured and related to the concentration of the target analyte. Most sensitive measurement of refractive index changes can be realized using Fabry Perot interferometers as transducers. In this talk I will introduce ICAPS (interferometric cavity assisted photothermal spectroscopy) and show how sub-ppb concentration levels can be detected by means of a balanced detection approach, and finally how this new gas sensor technology can be miniaturized and possibly integrated on a single chip. With respect to liquid sensing the basic concepts of thermal lens, thermal mirror and thermal beam deflection will be presented and application on the measurement of solutes in organic solvents as well as water presented. Also concerning liquid sensing, I will introduce the efforts under way toward sensor miniaturization, mainly using photonic integrated circuitries, such as micro-ring resonators (MRR) and Mach Zehnder Interferometers (MZI) as transducers to detect absorption induced temperature and hence refractive index changes of the sample.