Chapter 5 Chromatography Combined with Bioassays and Other Hyphenations – The Direct Link to the Compound Indicating the Effect Gertrud E. Morlock * Justus Liebig University Giessen, Interdisciplinary Research Center (IFZ), Institute of Nutritional Science, Chair of Food Science, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany * E-mail: gertrud.morlock@ernaehrung.uni-giessen.de. An actual interesting branch is effect-directed analysis. Recent progress in the ield of the application of bioassays in direct combination with chromatography (direct bioautography) led to reliable characterization of unknown samples with regard to their activity proile. Planar chromatograms were directly immersed into bioassays, followed by incubation on the plate for up to 2 hours and visualization of the activity proile via a color substrate reaction. Despite the long incubation time in the aqueous media, sharp high-performance thin-layer chromatography (HPTLC) zones were obtained, allowing quantitation. Also instant bioluminescent bioassays were employed. Bacteria, yeast cells or enzymes speciically and sensitively detect bioactive compounds in complex samples according to their distinct effect. HPTLC in combination with bioassays, derivatization reagents, spectroscopic and high-resolution mass spectrometric detections led to a fast activity proiling and the direct link to the bioactive compounds of interest in complex raw samples. All these tools, inclusive of structure elucidating methods like NMR, FTIR, SERS and HRMS, were performed at the analytical level directly from the bioactive zone of interest on the HPTLC plate, optionally via the versatile TLC-MS Interface. The image-giving chromatographic system with an open, planar stationary phase and the post-chromatographic evaporation of the mobile phase eased the performance of various kinds of hyphenations. © 2014 American Chemical Society Downloaded by UNIV OF MICHIGAN ANN ARBOR on February 18, 2015 | http://pubs.acs.org Publication Date (Web): December 16, 2014 | doi: 10.1021/bk-2014-1185.ch005 In Instrumental Methods for the Analysis and Identification of Bioactive Molecules; Jayprakasha, et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 2014.