Development of new in vitro models based on the use of electrospun scaffolds and their imaging by multiphoton microscopy coupled with fluorescence lifetime imaging microscopy

Abstract

In this thesis, new possible applications of electrospun scaffolds are presented. Besides, the interaction of human dermal fibroblasts (HDFs) with the materials has been investigated using multiphoton microscopy (MPM) coupled with fluorescence lifetime imaging microscopy (FLIM), using a non-invasive, marker-free approach. In the first part of the thesis, pure poly-L-lactide (PLA) scaffolds were obtained and characterized as delivery systems for Diclofenac sodium salt (DCF) and a synthetically obtained prodrug of it for the treatment of actinic keratosis. The Diclofenac prodrug was obtained via solid phase peptide synthesis using a versatile, clean, high yielding procedure. Besides, the drug encapsulation and its release from the scaffold could be imaged using MPM. Moreover, when working with the unmodified DCF we were able to control the release profile by adding small amounts of dimethyl sulfoxide. The DCF-loaded scaffold was used as a delivery system to induce in vitro cell death in HDFs. The target cells were imaged using MPM coupled with FLIM, using a non-invasive, marker-free in vitro model to investigate drug effects. In the last part of the thesis, we produced and characterized different hybrid gelatin/PLA scaffolds. In this case, the goal was to obtain well-blended scaffolds with tunable properties, such as porosity, hydrophobicity and wettability... [edited by Author]