Preparation, characterization and antimicrobial property of micro-nano sized Na-borosilicate glass powder with spherical shape

Spherical glass powders are potential materials for the production of a high performance coating where uniform porosities are obtainable with a high hydrophilic nature. Coating with antimicrobial properties increases the engineering properties of the materials. In this study, Ag₂O doped (0.5-5 wt.% Ag₂O) Na-borosilicate micro (1.227 μm) and nano (134 nm) sized glass powders were prepared by ultrasonic spray pyrolysis. The antimicrobial properties against gram positive bacteria (Bacillus cereus and Staphylococcus aureus), gram negative bacteria (Escherichia coli) and yeast (Candida albicans) were determined using the agar-disc diffusion and modified agar well methods. The results show that the prepared powders are spherical, of amorphous structure and have a very smooth surface. The increase in silver oxide content increased the powders' antimicrobial activity. Powders with 2.5 wt.% Ag₂O content are highly active (?) against the three types of microorganisms. The nano sized powder also increased antimicrobial activity.