Synthesis and Physicochemical Evaluation of Bees' Chitosan-Based Hydrogels Modified with Yellow Tea Extract.

Sonia Kudłacik-Kramarczyk,Anna Jaromin,Anna Czopek,Magdalena Głąb,Agnieszka Zagórska,Paweł Gajda,Anna Drabczyk,Bożena Tyliszczak

doi:10.3390/ma14123379

Abstract

The novelty of the research involves designing the measurement methodology aimed at determining the structure–property relationships in the chitosan-based hydrogels containing yellow tea extract. Performed investigations allowed us to determine the swelling properties of hydrogels in selected time intervals, evaluate the mutual interactions between the hydrogels and simulated physiological liquids via pH measurements and directly assess the impact of such interactions on the chemical structure of hydrogels using Fourier transform infrared (FT-IR) spectroscopy and their wettability by the measurements of the flatness of the drop on the surface of the tested samples via the static drop method. Next, the surface morphology of hydrogels was characterized by the Scanning Electron Miscorcopy (SEM) and their elasticity under the tension applied was also verified. It was proved that incubation in simulated physiological liquids resulted in a decrease in contact angles of hydrogels, even by 60%. This also caused their certain degradation which was reflected in lower intensities of bands on FT-IR spectra. Further, 23% v/v yellow tea extract in hydrogel matrices caused the decrease of their tensile strength. An increase in the amount of the crosslinker resulted in a decrease in the sorption capacity of hydrogels wherein their modification caused greater swelling ability. In general, the investigations performed provided much information on the tested materials which may be meaningful considering their application, e.g., as dressing materials.

Highlights

Introduction iationsHydrogels belong to the group of polymers with growing interest in many fields including medicine and the relative areas [1,2,3]
Based on the performed syntheses, it was observed that in some cases crosslinked hydrogel sample was not obtained as a result of 2 min treatment with UV radiation. Such a conclusion was drawn in the case of the reaction mixture containing 33% v/v yellow tea extract and 3.2 mL of the crosslinker which was not crosslinked during the reaction
The methodology applied allowed to provide information on the behavior of the drop of water dosed on the surface of the tested hydrogels as well as on the impact of the chemical compositions and pH of SBF solution on hydrogel wettability

Summary

Introduction

Hydrogels belong to the group of polymers with growing interest in many fields including medicine and the relative areas [1,2,3]. Their popularity results from many unique properties including, e.g., the ease of modification with compounds of various origin and properties [4,5,6]. There are many methods that may be applied to characterize the mechanical properties of hydrogels, e.g., ring extensiometry, strip extensiometry, compression test, indentation test or bulge test. These analyses are destructive and in the case of Licensee MDPI, Basel, Switzerland

Methods

Results

Conclusion