title: Combination of patch clamp and Raman spectroscopy for single-cell analysis.
abstract: In this contribution we present the combination of patch clamp with Raman spectroscopy for a label-free quantitative detection of intracellular components. Patch clamp is used to gain controlled access to the cytosol and internalize water-soluble compounds into the cell. The presence and concentration of these substances inside the living mammalian cell are probed by means of Raman spectroscopy in a label-free manner. A proof of principle was given using the carotinoid crocin as a sample compound that does not show specific interaction with the cell. When the intracellular crocin concentration as determined from the Raman spectra was monitored, the kinetics of internalization/diffusion into the cell could be characterized by a single-exponential function. Furthermore, the technique was successfully applied to observe differences in the internalization of free and protein-bound heme into the living cell. Although the peptide-capped microperoxidase MP-11 did not show specific interactions, free heme accumulated in the cell by binding to cellular components.
authors.affiliation: Institute of Photonic Technology, Albert-Einstein-Strasse 9, 07745 Jena, Germany.
authors.forename: Ute
authors.initials: U
authors.lastname: Neugebauer
authors.forename: Stefan H
authors.initials: SH
authors.lastname: Heinemann
authors.forename: Michael
authors.initials: M
authors.lastname: Schmitt
authors.forename: Jürgen
authors.initials: J
authors.lastname: Popp
mesh_terms: D002338:Carotenoids / Q000378:metabolism; D002470:Cell Survival; D057809:HEK293 Cells; D006427:Hemin / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D018408:Patch-Clamp Techniques / Q000379:methods*; D010455:Peptides / Q000378:metabolism; D059010:Single-Cell Analysis / Q000379:methods*; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D010455:Peptides; D002338:Carotenoids; D006427:Hemin; C029036:crocin