en مواد و الیاژ Materials and alloys Research Paper Research Paper <span style="font-size:12pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span style="font-size:14.0pt"><span style="line-height:150%"><span new="" roman="" style="font-family:" times="">The spread of pathogenic microorganisms in the food, pharmaceutical and active packaging industries has created serious health and economic challenges. Among them, zinc oxide (ZnO) nanoparticles have attracted attention as effective antimicrobial agents; however, particle aggregation and functional limitations limit their individual application. The aim of this study was to synthesize ZnO nanoparticles and prepare ZnO@HA and ZnO@PVP nanocomposites and comprehensively evaluate their structural, optical and antibacterial properties. ZnO nanoparticles were synthesized by sol-gel method and nanocomposites were prepared by solution mixing and polymer coating methods, respectively. The X-ray diffraction results confirmed the formation of hexagonal wurtzite structure of ZnO with characteristic peaks at 31.8, 34.4 and 36.3 degrees, indicating the appropriate phase purity of the samples. The FTIR spectra showed the presence of a characteristic Zn-O band around 500 cm⁻&sup1; and in the composite samples the presence of phosphate groups related to HA and organic PVP groups was clearly observed, indicating the success of the phase interaction. FESEM images showed that pure ZnO has a nanoscale aggregated granular morphology; while the addition of HA caused a decrease in particle size and the formation of a dense and uniform nanostructured network. In contrast, in the ZnO@PVP sample, spherical structures were observed on the micrometer scale, indicating an increase in particle aggregation. Optical studies have shown that a characteristic absorption peak of ZnO appears at around 375 nm. The energy gap values ​​for pure ZnO, ZnO@HA, and ZnO@PVP were 3.13, 1.75, and 4.13 eV, respectively. The antibacterial test against &quot;<i>Escherichia coli</i>&quot; showed that ZnO@HA nanocomposite is a promising candidate for antimicrobial applications, active packaging, and biomedical systems due to its stable nanometer size, reduced energy gap, and enhanced antibacterial activity.</span></span></span></span></span></span> ZnO@HA and ZnO@PVP nanocomposite,antibacterial activity,sol-gel method,physical and optical characterizations 0 0 http://ijmse.iust.ac.ir/browse.php?a_code=A-10-6316-1&slc_lang=en&sid=1 Hussein Mohamed Sadeq boshrags.bg@gmail.com No Al-Furat Al-Awsat Technical University, Polytechnic College-Karbala, Mechanical Technologies Engineering Department, Iraq Hamzah Zahraa Saad zahraa.saad@s.uokerbala.edu.iq No 1Al-Furat Al-Awsat Technical University, Polytechnic College-Karbala, Mechanical Technologies Engineering Department, Iraq Layth Hayder Hameed Kazem Al_Tmamimi laith.hamid.ikr14@atu.edu.iq No Al-Furat Al-Awsat Technical University, Polytechnic College-Karbala, Mechanical Technologies Engineering Department, Iraq Mohammed Ridha Shaeed Janabi wsci.mohammed.aljanabi@uobabylon.edu.iq Yes 2University of Babylon, Science for women, Laser Physics, Babylon, Iraq Tabarek Falah Deindee sci.tabarek.salim@uobabylon.edu.iq No University of Babylon, College of Science, Department of Physics, Babylon, Iraq