Synthesis and Antibacterial Properties of Novel ZnMn₂O₄–Chitosan Nanocomposites

• Main Authors: Rajiv Gandhi Packirisamy, Chandramohan Govindasamy, Anandhavelu Sanmugam, K. Karuppasamy, Hyun-Seok Kim, Dhanasekaran Vikraman
• Format: Article
• Language: English
• Published: MDPI AG 2019-11-01
• Series: Nanomaterials
• Subjects: znmn₂o₄; mn₃o₄; chitosan; nanocomposites; antibacterial
• Online Access: https://www.mdpi.com/2079-4991/9/11/1589

The development of productive antibacterial agents from nontoxic materials via a simple methodology has been an immense research contribution in the medicinal chemistry field. Herein, a sol&#8722;gel one-pot reaction was used to synthesize hybrid composites of hausmannite&#8722;chitosan (Mn₃O₄&#8722;CS) and its innovative derivative zinc manganese oxide&#8722;chitosan (ZnMn₂O₄&#8722;CS). Fixed amounts of CS with different metal matrix <i>w</i>/<i>v</i> ratios of 0.5%, 1.0%, 1.5%, and 2.0% for Mn and Zn precursors were used to synthesize ZnMn₂O₄&#8722;CS hybrid composites. X-ray diffraction analysis indicated the formation of polycrystalline tetragonal-structured ZnMn₂O₄ with a CS matrix in the hybrids. Fourier-transform infrared spectroscopic analysis confirmed the formation of ZnMn₂O₄&#8722;CS hybrids. Detailed investigations of the surface modifications were conducted using scanning electron microscopy; micrographs at different magnifications revealed that the composites&#8217; surface changed depending on the ratio of the source materials used to synthesize the ZnMn₂O₄&#8722;CS hybrids. The antibacterial activity of the Mn₃O₄&#8722;CS and ZnMn₂O₄&#8722;CS composites was tested against various bacterial species, including <i>Bacillus subtilis</i>, <i>Escherichia coli</i>, <i>Salmonella typhi</i>, and <i>Pseudomonas aeruginosa.</i> The zone of inhibition and minimum inhibitory concentration values were deduced to demonstrate the efficacy of the ZnMn₂O₄&#8722;CS nanocomposites as antibacterial agents.