Hypericin inclusion complexes encapsulated in liposomes for antimicrobial photodynamic therapy

Publication date: Available online 5 September 2019Source: International Journal of PharmaceuticsAuthor(s): Nikola Plenagl, Benjamin Sebastian Seitz, Lili Duse, Shashank Reddy Pinapireddy, Jarmila Jedelska, Jana Brüßler, Udo BakowskyAbstractThe naturally occurring anthraquinone derivative hypericin is a highly potent photosensitiser. Several in vitro studies show high phototoxicity of the pigment towards gram-positive bacteria. Nevertheless, the highly lipophilic nature and poor bioavailability prevent its application in daily clinical practice thus leading to a limited therapeutic value of hypericin. Liposomal encapsulation could help overcome these limitations and would make hypericin available for daily clinical practice. The use of liposomes as carriers for hypericin in antimicrobial photodynamic therapy (aPDT) is quite new. The aim of this work was to improve the photodynamic efficiency of the previously mentioned carriers by entrapping hypericin in the aqueous compartment of the liposomes. Therefore, a water-soluble inclusion complex of hypericin and (2-hydroxypropyl)-beta-cyclodextrin (Hyp-HPβCD) was prepared. After encapsulation of the inclusion complex into DSPC and DSPC/DPPC/DSPE-PEG liposomes with the dehydration-rehydration vesicle (DRV) method, the formulations were physicochemical characterised. The photodynamic efficiency towards the gram-positive model strain Staphylococcus saprophyticus subsp. bovis. was tested on planktonic cells as well as on biofilms. D...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research