title: Protoporphyrin IX-accumulation in human tumor cells following topical ALA- and h-ALA-application in vivo.
abstract: The fluorescence monitoring represents an innovative approach to detect tumor tissue by photosensitizer-mediated fluorescence. Therefore, information on cellular uptake, tumor selectivity and accumulation properties of photosensitizers are of essential interest. In this study we compared the accumulation properties of two photosensitizer precursors, the 5-aminolaevulinic acid (ALA) and a hexylester of ALA (h-ALA), in vivo using the hen's egg model and the human larynx carcinoma cell line HEp-2. The formation of the actual photosensitizer, protoporphyrin IX (PpIX), was determined both qualitatively and quantitatively. The intensity of the excited PpIX-fluorescence was observed as an indicator for the presence of PpIX after topical ALA- and h-ALA-applications. PpIX-fluorescence was measured using spatially resolved fluorescence spectroscopy.
authors.affiliation: Department of Human Biology and Human Genetics, The University, P.O. Box 3049, D-67653 Kaiserslautern, Germany. vzenzen@rhrk.uni-kl.de
authors.forename: Volker
authors.initials: V
authors.lastname: Zenzen
authors.forename: Heinrich
authors.initials: H
authors.lastname: Zankl
mesh_terms: D000287:Administration, Topical; D000482:Allantois / Q000378:metabolism; D000622:Aminolevulinic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics*; D000818:Animals; D002642:Chick Embryo; D005260:Female; D006801:Humans; D007822:Laryngeal Neoplasms / Q000378:metabolism* / Q000473:pathology; D017319:Photosensitizing Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D011524:Protoporphyrins / Q000008:administration & dosage / Q000493:pharmacokinetics*; D013050:Spectrometry, Fluorescence; D014407:Tumor Cells, Cultured
chemical_list: D017319:Photosensitizing Agents; D011524:Protoporphyrins; D000622:Aminolevulinic Acid; C028025:protoporphyrin IX; C419924:5-aminolevulinic acid hexyl ester