Abstract: | Synthesis of iron nanoparticles (INPs) with a biocompatible coating usually is a multistep process which requires harsh, special and protected reaction conditions. In the current experiment, the authors used Xanthomonas campestris cells to develop a facile method for fabrication of biocompatible INPs. Bacterial cells were supplied with ferric citrate as an iron precursor. Transmission electron microscopy micrographs exhibited that xanthan gum‐coated INPs are synthesised and deposited on the surface of X. campestris cells and produced nanoparticles were 20–80 nm in diameter with 41.7 nm mean particle size. Xanthan gum coating with about 7 nm thickness formed a clear hollow around each nanoparticle. According to thermogravimetric analysis, the coating was about 13.4% of the total INPs weight. Prepared particles had a zeta potential of −114 mv which is an ideal surface charge to make particles colloidally stable in aqueous matrixes. Xanthan gum‐coated INPs were non‐crystalline with low saturation magnetisation value of about 0.26 emu/g.Inspec keywords: nanoparticles, nanofabrication, iron, microorganisms, transmission electron microscopy, particle size, electrokinetic effects, surface charging, magnetisation, organic compoundsOther keywords: biosynthesis, xanthan gum‐coated INPs, Xanthomonas campestris cells, iron nanoparticles, biocompatible coating, bacterial cells, ferric citrate, transmission electron microscopy micrographs, mean particle size, thermogravimetric analysis, zeta potential, surface charge, saturation magnetisation, size 20 nm to 80 nm, Fe |