Structural properties of xanthan gum hydrogels: preliminary study for future incorporation of B12 vitamin

Resumo

Growing social concern about health has increased interest in new functional foods. To meet this demand, hydrogels represent a promising alternative: semisolid structures with a high water-retention capacity that can act as drug-encapsulating systems. Hydrogels are composed of structuring agents, generally biopolymers, capable of promoting gelation. Xanthan gum (XG) can increase the medium's viscosity through molecular interactions with other components. Thus, evaluating its gelling behavior in the incorporation of B12 vitamin into hydrogels becomes essential. Hydrogels were prepared using four concentrations of xanthan gum: XG1 (0.5% w/v), XG2 (0.75% w/v), XG3 (1.0% w/v), and XG4 (1.5% w/v). Samples were analyzed for moisture content, gel fraction, swelling index, and Raman spectroscopy, and statistical significance was assessed. The moisture content of all samples remained between 98% and 99%. The highest gel fraction values were observed for XG2 and XG3 85.33% and 82.4%, respectively, indicating more efficient network formation. The swelling index ranged from 25.64 to 28.66 g/g across samples. Raman spectroscopy revealed characteristic peaks for all formulations, including C–H vibrations, ester groups, and asymmetric and symmetric CH₂ and CH₃ stretching modes. Overall, intermediate concentrations of xanthan gum proved more efficient for producing hydrogels suitable for future vitamin incorporation.