Synergic effect of sodium alginate and Citrus lemon extract on the in-situ synthesis of AgNPs in a polymeric matrix

Abstract

The aim of this work was to prepare a polymer matrix nanocomposite doped with silver nanoparticles (AgNPs) and to evaluate the size and distribution of the nanoparticles in the alginate matrix. Also, the antibiofilm properties of the prepared composites were evaluated. The nanoparticles were synthesized in an alginate matrix by the in-situ method. The prepared nanoparticles had a wide size range (∼20% were up to 30 nm in diameter and larger particles (up to 90 nm) were also observed). To improve the AgNPs synthesis, Citrus lemon extract was added. The synergic effect of alginate and Citrus lemon extract on the in-situ synthesis of the AgNPs was proved (85% of the synthesized nanoparticles were <30 nm in diameter). Subsequently, thin films of alginate-AgNPs composites were prepared by spin coating and stabilized with a calcium chloride solution. The synthesis of the AgNPs and the presence and distribution of the AgNPs in the polymer matrix nanocomposites were evaluated by UV–Vis, FTIR, TEM, SEM and EDX analyses. The in-situ synthesis of the nanoparticles ensured the homogeneous distribution of the nanoparticles in the matrix. Due to the presence of silver nanoparticles in the alginate-based composite films, the antibiofilm effect of the polymer matrix composite was proved.