RESUMO
In this study we present a novel silver complex of hyaluronan-lipoate (SHLS12) in a gel-state form. NMR analysis, conductometry and elemental analysis demonstrated stable non-covalent interactions between silver ions and the polysaccharide-lipoate backbone, whereas rheological investigations confirmed its gel-like physical-chemical behavior. Biological studies showed the ability of SHLS12 to exert a straightforward activity against different bacterial strains grown in sessile/planktonic state. The biocompatibility was also proved toward two eukaryotic cell lines. By considering both its ability to preserve antibacterial properties when exposed to the serum protein BSA and its low susceptibility to be degraded by hyaluronidase enzyme, this novel complex may be considered as a promising biomaterial for future in vivo applications.
Assuntos
Antibacterianos/síntese química , Materiais Biocompatíveis/síntese química , Ácido Hialurônico/análogos & derivados , Ácido Hialurônico/química , Ácido Tióctico/análogos & derivados , Ácido Tióctico/química , Células 3T3 , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Biofilmes/efeitos dos fármacos , Géis/síntese química , Géis/química , Géis/farmacologia , Humanos , Ácido Hialurônico/síntese química , Camundongos , Prata/química , Ácido Tióctico/síntese químicaRESUMO
The synthesis and physicochemical characterisation of mixed lipoic and formic esters of hyaluronan (Lipohyal) are presented in this paper. The synthesis was conducted by activating lipoic acid with 1,1'-carbonyldiimidazole to obtain lipoyl imidazolide, which reacted with hyaluronan (HA) in formamide under basic conditions. This procedure allows researchers to modulate easily the degree of substitution over a range of 0.05-1.8. Radical scavenger properties were analysed by UV-vis spectroscopy, where improved performance was demonstrated for Lipohyal with respect to the HA row material and lipoic acid. The chemical modification also causes HA to show an improved resistance to hyaluronidase digestion. These findings show that Lipohyal is a highly interesting derivative for applications in the tricological and dermo-cosmetic field and as an anti-aging ingredient. Moreover, Lipohyal can be easily crosslinked by UV irradiation, resulting in an innovative hydrogel with distinctive viscoelastic properties that is suitable as both a dermal-filler and as an intra-articular medical device.
