**Preface to "Gels: Synthesis, Characterization and Applications in High Performance Chemistry"**

Organogels, hydrogels, and ionic gels have been investigated both in a theoretical and experimental manner. The research performed was focused on their synthesis and applications in high-performance chemistry and its important branches. All the above-mentioned gels were characterized from structural and supramolecular points of view by FTIR, NMR, X-ray diffraction, and POM. The keywords proposed in this reprint were as follows: organogels, hydrogels, ionic gels, chitosan, and fractal analysis. These terms were extremely pertinent to this research piece, hereby presented. As a result, all reference themes, as well as those associated with them, were touched upon in this reprint. We mention that the articles in this selection focused on one or more of the topics listed above.

The hydrogel investigation for wound-healing applications has been also well depicted. The hydrogel biodegradation has been monitored in media mimicking the wound exudate by gravimetrical measurements, SEM imaging, and SEM fractal analysis of representative images. The pictures of interest could be evaluated by fractal analysis, calculating the fractal parameters, respectively, fractal dimension and lacunarity values, as a quantitative measure of the homogeneity of the material and its texture through their topological analysis in some of the reference works. As a consecration of these studies developed on this occasion, materials biocompatibility, antimicrobial properties, and biodegradation have been considered in vitro in relevant scientific works that were referenced and included in this volume.

> **Viorel-Puiu Paun** *Editor*
