title: Visualization and quantification of polymer distribution in microcapsules by confocal laser scanning microscopy (CLSM).
abstract: Confocal laser scanning microscopy (CLSM) was employed in order to characterize microcapsules. Microcapsules were prepared by complex coacervation: gelatin and arabic gum were labelled with fluorescent markers. In the capsule wall a homogeneous distribution for both gelatin and arabic gum throughout the capsule wall was depicted. By the use of CLSM and a computational image analysis the quantification of the labelled polymer in the wall material was possible. Adding fluorescently labelled casein as a macromolecular model compound to the coacervation process, a gradiental distribution in the wall material was observed with highest concentration of casein at the oil-wall interface. The influence of casein concentration on its deposition behaviour in the capsule wall was imaged successfully and thereafter quantified by computational image analysis.
authors.affiliation: Department of Biopharmaceutics and Pharmaceutical Technology, Saarland University, Im Stadtwald, D-66123, Saarbrücken, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Lamprecht
authors.forename: U F
authors.initials: UF
authors.lastname: Schäfer
authors.forename: C M
authors.initials: CM
authors.lastname: Lehr
mesh_terms: D002214:Capsules / Q000737:chemistry*; D002364:Caseins / Q000737:chemistry; D004339:Drug Compounding; D004655:Emulsions; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D005780:Gelatin / Q000737:chemistry; D006170:Gum Arabic / Q000737:chemistry; D007091:Image Processing, Computer-Assisted; D018613:Microscopy, Confocal; D011108:Polymers / Q000737:chemistry*
chemical_list: D002214:Capsules; D002364:Caseins; D004655:Emulsions; D005456:Fluorescent Dyes; D011108:Polymers; D006170:Gum Arabic; D005780:Gelatin; D016650:Fluorescein-5-isothiocyanate