In Situ Infrared Spectroscopy
In situ infrared (IR) spectroscopy is a spectroscopic method for the infrared spectral range which can be used in defined environments during preparation, modification, function, and reaction or analysis in natural environment. In this contribution especially liquid environments are considered with the focus on the mid-infrared (MIR) spectral range from 2.5 to 16 μm.
Key Research Findings
Cell geometries as given in Fig. 2 are successfully applied in current research for chemical, physical, and biotechnological applications. A single reflection ATR geometry (Fig. 2b), for example, was implemented in an electrochemical cell and also used for the study of dissociation of carboxylic groups . Also for studies of liver cells in combination with an IR microscope, a single reflection ATR crystal was used. Single reflection measurements with polarization-dependent spectroscopy (Fig. 2a) and ellipsometry were performed in a reflection cell below the ATR regime for the monitoring of electrochemical etching and growth of polymeric films, modification of pH- and temperature-responsive polymer brushes as well as protein adsorption thereon [3, 5]. Multiple reflection geometries (Fig. 2c), e.g., were established for catalytic studies  and voltammetric studies .
In situ IR spectroscopy is interesting for a broad range of technological applications, e.g., in (i) biomedicine and biochemistry, (ii) electrochemistry, (iii) catalyses, and (iv) microfluidic devices. In particular, it is relevant for the design of functional templates for drug release , studies of smart films and surfaces , characterization of living cells in contact with solution , control during electrochemical preparations , monitoring and understanding of catalytic processes , and microfluidics. It can be expected that advanced infrared technology, e.g., new IR lasers and detectors, bring advances in the used infrared methods, e.g., by the use of the new technology in combination with smart sensing devices or microfluidic devices.
- 1.Griffiths PR, Chalmers J (eds) (2002) Handbook of vibrational spectroscopy. Wiley, ChichesterGoogle Scholar
- 5.Hoy O, Zydrko B, Lupitskyy R, Sheparovych R, Aulich D, Wang J, Bittrich E, Eichhorn K-J, Uhlmann P, Hinrichs K, Müller M, Stamm M, Minko S, Luzinov I (2010) Synthetic hydrophilic materials with tunable strength and a range of hydrophobic interactions. Adv Funct Mater 20:2240–2247CrossRefGoogle Scholar
- 11.Part V (2014) Developments in Ellipsometric Real-Time/In-situ Monitoring Techniques. In: Hinrichs K, Eichhorn K-J. (eds) Ellipsometry of Functional Organic Surfaces and Films: Springer Berlin Heidelberg, pp 249–301Google Scholar