In vitro antibacterial response of ZnO‐MgO nanocomposites at various compositions

Abstract ZnO‐MgO nanocomposites were prepared by a co‐precipitation method and afterward compared with pristine ZnO and MgO accordingly. XRD and EDX spectra were used to confirm the crystal structure and crystallite size of these materials. X‐ray diffraction analysis shows that antibacterial activity of ZnO:MgO composite enhances with crystallite size reduction ~1.34 times in comparison to pristine ZnO or MgO specimens, accompanied by domination of defect generation over defect annihilation activity. Besides, average particle sizes also reduce to ~2 times at 1:3 MgO/ZnO composite in comparison to MgO. The particle size of ZnO was substantially higher due to rod‐like morphology. Moreover, the minimum inhibitory concentration outcomes also show that ZnO‐MgO composites are more effective against gram‐negative pathogens in appropriate ratios (ZnO:MgO) of 1:3 and 3:1 with the concentration of 15,000 µg/ml. Similarly, gram‐positive pathogens were In contrast, ZnO and MgO separately or in 1:1 composite ratio does not prove considerably effective on all the five microbes (required higher >25,000 µg/ml) MIC to counter gram‐negative pathogens. Additionally, lower doses of 3ZnO:1MgO and 1ZnO:3MgO ~5000 µg/ml composite nanoparticles are effective on gram‐positive pathogens. Similarly, 3ZnO:1MgO composition proved highly productive at a much lower concentration, that is, 12500 ≤ X ≤ 15000 to counter gram‐negative pathogens. Besides, 1ZnO:3MgO is effective against gram‐negativepathogens at MIC ranging from 12500 ≤ X ≤ 15000 µg/ml.