title: A new method for microcapsule characterization: use of fluorogenic genipin to characterize polymeric microcapsule membranes.
abstract: Numerous microcapsule systems have been developed for a wide range of applications, including the sustained release of drugs, cell transplantation for therapy, cell immobilization, and other biotechnological applications. Despite the fact that microcapsule membrane is a dominant factor governing overall microcapsule performance, its characterization is challenging. We report a new method for characterizing microcapsule membranes, using the most common alginate-poly-L-lysine-alginate (APA) microcapsule as an example. Our data demonstrate that genipin, a naturally derived reagent extracted from gardenia fruits, interacts with poly-L-lysine (PLL) and generates fluorescence. This fluorescence allows clear visualization and easy analysis of the PLL membrane in the APA microcapsules using confocal laser scanning microscopy. The results also show that PLL binding correlates to the reaction variables during PLL coating such as PLL concentration and coating time. In addition, five other different microcapsule formulations consisting of PLL and/or chitosan membranes were examined, and the results imply that this method can be extended to characterize a variety of microcapsule membranes. These findings suggest that genipin can serve as a fluorogenic marker for rapid characterization of microcapsule membranes, a superior method that would have important implications for microcapsule research and potential in many other applications.
authors.affiliation: Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering and Artificial Cells and Organs Research Centre, Faculty of Medicine, McGill University, 3775 University Street, Montreal, QC H3A, 2B4 Canada.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Chen
authors.forename: Wei
authors.initials: W
authors.lastname: Ouyang
authors.forename: Bisi
authors.initials: B
authors.lastname: Lawuyi
authors.forename: Trisna
authors.initials: T
authors.lastname: Lim
authors.forename: Satya
authors.initials: S
authors.lastname: Prakash
mesh_terms: D002214:Capsules / Q000032:analysis* / Q000737:chemistry*; D057889:Iridoid Glycosides; D039823:Iridoids; D008422:Materials Testing / Q000379:methods; D008567:Membranes, Artificial; D018613:Microscopy, Confocal / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods*; D011108:Polymers / Q000032:analysis / Q000737:chemistry; D011714:Pyrans / Q000032:analysis* / Q000737:chemistry*
chemical_list: D002214:Capsules; D057889:Iridoid Glycosides; D039823:Iridoids; D008567:Membranes, Artificial; D011108:Polymers; D011714:Pyrans; C007834:genipin