Antibacterial Hydrogel as a Self-Drug-Delivery System Derived from Zn(II)-bis-imidazole/NSAID-Based Organic-Inorganic Hybrids.

A skin wound is prone to bacterial infection and growth. An antibacterial topical hydrogel that can act as a self-drug-delivery (SDD) system is reported here. Two bidentate ligands () derived from imidazole/benzimidazole derivatives when reacted with Zn(NO) and a series of nonsteroidal-anti-inflammatory drugs (NSAIDs) produced crystalline products, which were characterized by single-crystal X-ray diffraction (SXRD). Simple mixing of the ingredients of the crystalline products (stoichiometry guided by the corresponding crystal structure) produced an aqueous gel (DMSO/water) when the bidentate ligand was water-insoluble , whereas water-soluble readily produced hydrogels under similar conditions. Dynamic rheology and scanning electron microscopy (SEM) were employed to characterize the gels. Zone inhibition diameters, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and hemolysis data suggested that among the hydrogelators, derived from , meclofenac and Zn(NO), was found to be the best against the Gram-negative bacteria . The corresponding hydrogel and a piece of a dried cloth bandage coated with the hydrogel also showed appreciable activity against . The antibacterial property of against , thus demonstrated, is relevant in developing an antibacterial SDD system because is reported to be present in infected wounds.