This work employs the concept of continuous-flow monitoring of chemical reactions by time resolved infrared (IR) spectroscopy. The key of this concept is the combination of a micro-machined infrared transparent chip for rapid mixing of two solutions and IR microspectroscopy along the outlet channel of the mixer, while the reagents are fed into the mixing chip at constant flow rate. The achievable time resolution is determined by the distance between two adjacent measurement spots. The capabilities of IR microscopy equipped with a globar or synchrotron IR source and an IR microscope employing a focal plane array (FPA) detector, for recording small sample spot sizes are investigated. A comparison of these instruments is given.
The function of the developed concept is outlined showing computational fluid dynamic simulations, which are supported by experimental results on test reactions. Further experimental results obtained of a biochemical reaction, the binding process between vancomycin, an important antibiotic, to a tripeptide involved in the build up of cell walls of gram positive bacteria is discussed as well.
Furthermore, the aim of this work is the evaluation of the ability of new instruments in the very far infrared region (FIR) or so-called terahertz (THz) range from 1 - 100 cm-1 for monitoring protein reactions in aqueous solution. Therefore, water and aqueous solutions of salts and sugars are measured with a THz-pulsed instrument and synchrotron FIR radiation coupled into an IR instrument. A concentration dependent increased absorption across the investigated THz spectral region is recorded for all studied chaotropic solutions, whereas the opposite is obtained for kosmotrope containing solutions.