Arak University Colloid & Nanoscience Journal 2980-9215 2 3 2024 12 01 Synthesis of ternary nickel-cobalt-palladium nanoparticle by microemulsion method and investigation of its antibacterial activity on Escherichia coli 390 396 721336 10.61186/CNJ.2.3.390 EN Bina Namakchi Department of Chemistry, Sanandaj Branch, Islamic Azad University, Sanandaj, Iran Hassan Saydi Department of Chemistry, Sanandaj Branch, Islamic Azad University, Sanandaj, Iran Journal Article 2025 01 20 In this research, nickel-cobalt-palladium nanoparticles were synthesized using the microemulsion method. The formation of nanoparticles, morphology, size and size distribution of nanoparticles was investigated using SEM, UV-Vis, and DLS methods. The UV-visible spectrophotometric results showed a peak in the region of 380-480 nm, confirming the presence of nanoparticles. The SEM results indicated spherical particle sizes in the range of 45-50 nm for the ratio of Ni:Co:Pd (1:1:1). Additionally, the DLS results showed a size range of produced nanoparticles between 50 and 100 nm, which is consistent with the SEM and UV-Visible results. Nickel-cobalt-palladium nanoparticles exhibited antibacterial properties against E. coli bacteria. The diameter of the zone of inhibition formed in samples containing nanoparticles was significantly larger than the diameter of the positive control sample and the negative control sample (without a zone of inhibition), thus confirming their antibacterial properties. https://cnj.araku.ac.ir/article_721336_04088fd163b9aea81dfdee4d7b8eb5a5.pdf