Lecithin as internal architecture modifier of hydrogels for model drug delivery systems with tunable properties

abstract

English

The purpose of this study focuses on the current and still developing topic of micro- and nanosized drug delivery systems, since their usage in treatment procedure offers a variety of benefits compared to conventional drug dosing. In recent years, specific extracellular matrix (ECM) imitating biopolymers carry exceptional properties of biocompatible and biodegradable materials, which are able to form soft or semi-solid networks beneficial for drug incorporation. Recent studies of innovative complex biomaterials have proved the potential of hydrogels usage for fabrication of novel materials, providing appropriate mechanical, chemical and biological characteristic for mimicking ECM for regenerative medicine, fabrication and in situ analyses of drug delivery systems [1-3]. Final properties related to specific application of these materials can be modified not only by polymer and/or crosslinking agent type and concentration, but actively also with other additives influencing inner architecture like phospholipid lecithin, which in water-based solutions forms organized structures [4]. In this proposed study the effect of lecithin additions on hydrogel matrix with various crosslinking principles was investigated. Selected systems were subjected to structural characterization in the form of xerogel as well as freeze dried form using direct visualization technique scanning electron microscopy (SEM). Further, these systems were rehydrated and the kinetics of swelling process was monitored. Changes in inner structure of hydrogels caused by addition of appropriate additive (e.g. lecithin) strongly influence key essential properties related to specific application such as mechanical or transport. Therefore, viscoelastic properties using rheometry as well as transport properties via macroscopic diffusion techniques has been performed. Following experiments consisted of characterization of viscoelastic behaviour via oscillatory rheology of rehydrated samples that were compared with freshly prepared hydrogels, as well as transport properties using macroscopic diffusion techniques, specifically by observing the release of model drug from the gel matrix.

hydrogel, lecithin, rheology, SEM, diffusion

HEGER, R.; KADLEC, M.; ZINKOVSKA, N.; TRUDIČOVÁ, M.; SMILEK, J.

6. 9. 2021

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