title: Flow cytometry of HEK 293T cells interacting with polyelectrolyte multilayer capsules containing fluorescein-labeled poly(acrylic acid) as a pH sensor.
abstract: Polyelectrolyte multilayer sensor capsules, 5 microm in diameter, which contained fluorescein-labeled poly(acrylic acid) (PAAAF) as pH-sensitive reporter molecules, were fabricated and employed to explore their endocytotic uptake into HEK 293T cells by flow cytometry. The percentage of capsules residing in the endolysosomal compartment was estimated from the fluorescence intensity decrease caused by acidification. Capsules attached to the extracellular surface of the plasma membrane were identified by trypan blue quenching. The number of capsules in the cytoplasm was rather small, being below the detection limit of the method. The advantages of polyelectrolyte multilayer capsules are that the fluorophore is protected from interaction with cellular compartments and that the multilayer can be equipped with additional functions.
authors.affiliation: Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstrasse 16-18, 04107 Leipzig, Germany.
authors.forename: Uta
authors.initials: U
authors.lastname: Reibetanz
authors.forename: David
authors.initials: D
authors.lastname: Halozan
authors.forename: Milan
authors.initials: M
authors.lastname: Brumen
authors.forename: Edwin
authors.initials: E
authors.lastname: Donath
mesh_terms: D000179:Acrylates / Q000737:chemistry; D000180:Acrylic Resins / Q000737:chemistry*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002772:Cholera Toxin / Q000494:pharmacology; D003593:Cytoplasm / Q000378:metabolism; D004337:Drug Carriers; D004573:Electrolytes / Q000737:chemistry*; D011992:Endosomes / Q000378:metabolism; D005434:Flow Cytometry; D019793:Fluorescein / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008247:Lysosomes / Q000378:metabolism; D018613:Microscopy, Confocal
chemical_list: D000179:Acrylates; D000180:Acrylic Resins; D004337:Drug Carriers; D004573:Electrolytes; C006903:carbopol 940; D002772:Cholera Toxin; C036658:acrylic acid; D019793:Fluorescein