Physicochemical Characterization of FRET-Labelled Chitosan Nanocapsules and Model Degradation Studies

Sub-micron o/w emulsions coated with chitosan have been used for drug delivery, quorum sensing inhibition, and vaccine development. To study interactions with biological systems, nanocapsules have been fluorescently labelled in previous works, but it is often difficult to distinguish the released la...

Authors: Hoffmann, Stefan
Gorzelanny, Christian
Moerschbacher, Bruno Maria
Goycoolea, Francisco Martin
Division/Institute:FB 13: Biologie
Document types:Article
Media types:Text
Publication date:2018
Date of publication on miami:28.05.2019
Modification date:28.06.2019
Edition statement:[Electronic ed.]
Source:Nanomaterials 8 (2018) 10, 846, 1-16
Subjects:chitosan; nanocapsules; degradation; FRET; protein corona; bioimaging
DDC Subject:570: Biowissenschaften; Biologie
License:CC BY 4.0
Language:English
Funding:Finanziert durch den Open-Access-Publikationsfonds 2018 der Deutschen Forschungsgemeinschaft (DFG) und der Westfälischen Wilhelms-Universität Münster (WWU Münster).
Format:PDF document
URN:urn:nbn:de:hbz:6-64189558360
Permalink:http://nbn-resolving.de/urn:nbn:de:hbz:6-64189558360
Other Identifiers:DOI: 10.3390/nano8100846
Digital documents:artikel_goycoolea_2018.pdf

Sub-micron o/w emulsions coated with chitosan have been used for drug delivery, quorum sensing inhibition, and vaccine development. To study interactions with biological systems, nanocapsules have been fluorescently labelled in previous works, but it is often difficult to distinguish the released label from intact nanocapsules. In this study, we present advanced-labelling strategies based on Förster Resonance Energy Transfer (FRET) measurements for chitosan-coated nanocapsules and investigate their dissolution and degradation. We used FRET measurements of nanocapsules loaded with equimolar concentrations of two fluorescent dyes in their oily core and correlated them with dynamic light scattering (DLS) count rate measurement and absorbance measurements during their disintegration by dissolution. Using count rate measurements, we also investigated the enzymatic degradation of nanocapsules using pancreatin and how protein corona formation influences their degradation. Of note, nanocapsules dissolved in ethanol, while FRET decreased simultaneously with count rate, and absorbance was caused by nanocapsule turbidity, indicating increased distance between dye molecules after their release. Nanocapsules were degradable by pancreatin in a dose-dependent manner, and showed a delayed enzymatic degradation after protein corona formation. We present here novel labelling strategies for nanocapsules that allow us to judge their status and an in vitro method to study nanocapsule degradation and the influence of surface characteristics.