In Vitro Characterization and Real-Time Label-Free Assessment of the Interaction of Chitosan-Coated Niosomes with Intestinal Cellular Monolayers
1 – Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki 00014, Finland
2 – Department of Pharmacy, University of Chieti – Pescara “G. d’Annunzio”, Chieti 66100, Italy
3 – Laboratory of Drug Targets Histopathology, Institute of Cardiology, Lithuanian University of Health Sciences, A. Mickeviciaus g. 9, Kaunas 44307, Lithuania
4 – Department of Life, Health & Environmental Sciences, University of L’Aquila, L’Aquila 67100, Italy.
5 – Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia.
6 – Department of Biomedical Engineering, University Medical Center Groningen, University of Groningen, Ant. Deusinglaan 1, Groningen 9713, The Netherlands
7 – W.J. Kolff Institute for Biomedical Engineering and Materials Science, University Medical Center Groningen, University of Groningen, Ant. Deusinglaan 1, Groningen 9713 The Netherlands
8 – Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Åbo Akademi University, Turku 20520, Finland
In vitro cell-based characterization methods of nanoparticles are generally static and require the use of secondary analysis techniques and labeling agents. In this study, bare niosomes and chitosan-coated niosomes (chitosomes) and their interactions with intestinal cells are studied under dynamic conditions and without fluorescent probes, using surface plasmon resonance (SPR)-based cell sensing. Niosomes and chitosomes were synthesized by using Tween 20 and cholesterol in a 15 mM:15 mM ratio and then characterized by dynamic light scattering (DLS). DLS analysis demonstrated that bare niosomes had average sizes of ∼125 nm, polydispersity index (PDI) below 0.2, and a negative zeta (ζ)-potential of -35.6 mV. In turn, chitosomes had increased sizes up to ∼180 nm, with a PDI of 0.2-0.3 and a highly positive ζ-potential of +57.9 mV. The viability of HT29-MTX, Caco-2, and Caco-2/HT29-MTX cocultured cells showed that both niosomes and chitosomes are cytocompatible up to concentrations of 31.6 μg/mL for at least 240 min. SPR analysis demonstrated that chitosomes interact more efficiently with HT29-MTX, Caco-2, and Caco-2/HT29-MTX cocultures compared to bare niosomes. The resulting SPR measurements were further supported by confocal microscopy and flow cytometry studies, which demonstrated that this method is a useful complementary or even alternative tool to directly characterize the interactions between niosomes and in vitro cell models in label-free and real-time conditions.