Synthesis and characterization of polyvinyl alcohol/corn starch/linseed polyol-based hydrogel loaded with biosynthesized silver nanoparticles.

Nanocomposite hydrogel film was prepared from Polyvinyl alcohol [PVA], Corn Starch [CS], Linseed oil polyol [LP], and silver nanoparticles [NP]. LP was prepared by epoxidation and hydration of Linseed oil [LO]. IR and NMR supported the insertion of hydroxyl groups in LP by epoxide ring opening reaction at epoxidized LO. Silver NP were biosynthesized using aqueous leaves' extract from locally grown Ocimum forsskaolii Benth [LEO] plant. FTIR, XRD, UV and TEM confirmed the synthesis of NP (size 30 to 39 nm). Transparent and foldable hydrogel film resulted by blending the constituents (PVA, CS, LP and NP), crosslinking by glutaraldehyde, at room temperature, and showed expansion in water, different pH solutions, biodegradation and good antibacterial and antifungal activity against tested microbes. Linseed polyol influenced the structure, morphology, hydrophilicity, improved swelling ability and thermal stability and accelerated biodegradation of hydrogel films. NP were well adhered to LP globules that were embedded in PVA/CS matrix as strung set of beads (LP globules) decorated with black pearls (spherical NP). Silver NP conferred antimicrobial behavior to hydrogel film as observed by antimicrobial screening on different microbes. The results were encouraging and showed that such hydrogel films may find prospective applications in antimicrobial packaging.