Facile synthesis of biogenic silica nanomaterial loaded transparent tragacanth gum hydrogels with improved physicochemical properties and inherent anti-bacterial activity

In this report, biogenic, crystalline (similar to 60.5 +/- 2%) bowknot structured silica nanoparticles (BSNPs) of length similar to 274 +/- 7 nm and width similar to 36 +/- 2 nm were isolated from invasive species viz. Lantana camara. These were then chemically modified using nitrogen containing moieties viz. APTES and CTAB. These modified BSNPs were then used as electrostatic cross-linking agents for the formation of tragacanth gum (TG) hydrogels. The cytocompatible CTAB@BSNP TG hydrogels documented similar to 10-12 fold enhancement in anti-bacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa when compared with TG hydrogels. Disruption of the bacterial membrane by ROS generation and protein leakage were responsible for anti-bacterial activity. A cell migration assay suggested that CTAB@BSNP TG augmented the cell proliferation of NIH-3T3 cells compared to other TG hydrogels. The present study will pave the path for the development of organic-inorganic hybrid nanocomposite-based hydrogels for anti-bacterial and cell migration applications.