𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Covalent and ionic co-cross-linking—An original way to prepare chitosan–gelatin hydrogels for biomedical applications

✍ Scribed by Anca N. Jătariu (Cadinoiu); Marcel Popa; Silvia Curteanu; Cătălina A. Peptu


Publisher
John Wiley and Sons
Year
2011
Tongue
English
Weight
740 KB
Volume
98A
Category
Article
ISSN
1549-3296

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

The first goal of this work was to develop a method for obtaining interpenetrating gelatin (G)–chitosan (CS) networks prepared by double cross‐linking (covalent followed by ionic) that exhibit hydrogel character. The second goal was to modulate their properties as a function of the preparation parameters by using neural network models. This study was therefore carried out by experiment and simulation. The covalent cross‐linking resulted from the reaction between the carbonyl groups of glutaraldehyde with amino groups belonging to both polymers; the ionic cross‐linking is based on the interaction between tripolyphosphate anions and protonated amine groups (ammonium ions) of the polymers. The total cross‐linking density (indirectly assessed by estimating the water swelling capacity) and the ability to include hydrosoluble bioactive principles are influenced by the following process parameters: the CS/G ratio, the amount of ionic cross‐linker, and the ionic cross‐linking time. The prepared hydrogels were characterized with respect to their structural, morphological, and some physical properties. The hydrogels ability to load high amounts of water‐soluble drugs indicates their potential use as carriers for biologically active principles in the human body. A neural network methodology was applied to model the swelling degree and caffeine loading/release capacity depending on reaction conditions; in addition, applying this method, the optimal preparation conditions have been determined, targeting pre‐established values for swelling degree or maximum caffeine value. The accuracy of the results obtained through this technique proves that the neural networks are suitable tools for modeling cross‐linking processes taking place complex nonlinear polymers. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 2011.