Synthesis, properties and antibacterial activity of Ca doped Zn₂SnO₄ nanoparticles by microwave assisted method

A major problem in world health care is the development of antibiotic resistance in bacteria. In light of this, pure and calcium-doped zinc tin oxide (ZTO) nanoparticles, Zn₂SnO₄ (S₁), Zn₂Sn_0.7Ca_0.3O₄ (S₂), Zn₂Sn_0.5Ca_0.5O₄ (S₃), and Zn₂Sn_0.3Ca_0.7O₄ (S₄), were synthesized via simple and cost effective microwave assisted method. The doping effect on antibacterial activity was studied in detail. The XRD spectrum revealed that all the deposited samples exhibited a spinel cubic structure. A decrease in crystallite size, an increase in strain and dislocation density was observed with an increase in Ca concentration. FESEM images exhibited an irregular and non-homogeneous nature with crystalline morphology having a physical dimension of nm size. EDAX confirmed the purity of deposited samples. We used the agar well diffusion technique to study the antibacterial activity of Gram-positive and Gram-negative bacteria. The doping of the ZTO matrix with Ca ions increased its antibacterial performance by 99% against Klebsiella pneumoniae bacteria, and its effectiveness was enhanced with increasing Ca ion concentration inside the Zn₂SnO₄ nanoparticles.