Calcium–cadmium ferrite (Ca1−xCdxFe2O4) was initially synthesized in various concentrations by using thermal treatment method. After the completion of the synthesis process, structural characteristics, morphology, and constituent elements of samples were determined via various techniques. The results of magnetic analyses confirmed the superparamagnetic behavior of the mentioned nanoparticles. Furthermore, UV–Vis analysis clearly indicated that band gap decreased with an increase in the particle size of these ferrites. The antibacterial activities of three samples were investigated against both Gram-positive and Gram-negative bacteria using inhibition zone method. Based on the results, CdFe2O4 had a negligible effect on gram-positive bacteria and no antibacterial impact on gram-negative bacteria. However, with the addition of calcium to cadmium ferrite, the obtained particle could inhibit the growth of both gram-positive and negative bacteria.
