For these reasons some chemical strategies are focused in back

to the nature approaches or, in other words, in improving the properties of natural polymers by chemical modifications.

We report that by using a simple chemical modification technique we can obtain new biomaterials, specifically suitable for biomedical applications. Concretely, we describe the chemical modification of gelatin and the suitable characteristics of the modified protein to develop new nanomedicines. This protein was selected because of its enormous potential in biomedicine, which is currently limited due to the difficulty of its use without toxic chemical crosslinkers. The modification of the protein was based on the transformation of the carboxylic group into amido groups selleck products after their reaction with polyamines, leading selleck chemical to a positively charged biopolymer. To cationize the gelatin two polyamines where used: ethylenediamine and spermine, the latter being one of the endogenous polyamines which

has a very positive influence over cells. This modification was monitored by physico-chemical techniques such as NMR, spectrophotometry and potentiometry.

With the most promising modified gelatins we were able to develop nanoparticles using the ionotropic gelation technique. In order to determine the ability of these new nanosystems to associate bioactive molecules we selected a model plasmid DNA. The developed nanosystems were characterized corroborating their ability to associate the genetic material. In conclusion, we were

able to obtain a semi-synthetic biomaterial with tunable physico-chemical properties, which can be used to develop new nanosystems with the ability to associate genetic material. We therefore propose that the gelatin, with its chemical modification, provide a unique biomaterial for the development of new nanomedicines.”
“The temperature-dependent transformation of pi-pi-stabilized stacked malvidin-catechin structures towards polymeric-type structures was studied by photoluminescence (PL) and anisotropy decay studies. The results show an immediate Cytoskeletal Signaling inhibitor decrease of the anisotropy decay after elevating the temperature from 293 K to 303 K or 313 K, while only a very slow increase in the anisotropy decay could be observed when the samples were kept at these elevated temperatures for a longer time such as a few days. The slow polymerization of the malvidin-polyphenol system could be identified as the main process responsible for the change in optical properties by the comparison of the time-dependence of the anisotropy decay with the change observed in the PL intensity. Measurements were also conducted in red wines, where we observed similar results. This suggests a possibly broader relevance of our results for all systems, where anthocyanins and polyphenols are present in considerable concentrations. (C) 2010 Elsevier Ltd. All rights reserved.