Silver substituted cobalt zinc ferrites as magnetic antimicrobials.

Silver-substituted cobalt zinc ferrite series, Co x Ag 0.5-x Zn 0.5 Fe 2 O 4 (x = 0.4, 0.3, 0.2, 0.1), is synthesized using the citrate gel method, wherein ferrite formation is achieved at 600 °C. The low-temperature crystallization results in agglomerated and porous ferrites. In this sample preparation methodology, as the silver content in the series increases, metallic silver deposits at the grain boundaries, and vacancies are created at the octahedral sites. With a further increase in silver content, the magnitude of magnetic properties decreases. Antimicrobial activity increases and further decreases with an increase in silver content. The composition Co 0.4 Ag 0.1 Zn 0.5 Fe 2 O 4 exhibits both magnetic and antimicrobial behaviour. These materials can potentially be beneficial in the manufacture of removable antimicrobial agents for water purification and drug delivery systems. [ABSTRACT FROM AUTHOR]