*Article* **Synthesis, Characterization, and Antibacterial Potential of Poly(***o***-anisidine)/BaSO4 Nanocomposites with Enhanced Electrical Conductivity**

**Mirza Nadeem Ahmad 1, Sohail Nadeem 2,\* , Raya Soltane 3,4 , Mohsin Javed 2, Shahid Iqbal 5,\* , Zunaira Kanwal 1, Muhammad Fayyaz Farid 1, Sameh Rabea <sup>6</sup> , Eslam B. Elkaeed <sup>6</sup> , Samar O. Aljazzar 7, Hamad Alrbyawi <sup>8</sup> and Walid F. Elkhatib 9,10**


**Abstract:** The poly(o-anisidine)/BaSO4 nanocomposites were prepared by oxidative polymerization of *o*-anisidine monomer with BaSO4 filler for the potential antibacterial properties of the composite materials. To achieve the optimal and tunable properties of the nanocomposites, the ratio of BaSO4 filler was changed at the rates of 1%, 3%, 5%, 7%, and 10% with respect to matrix. Different analytical techniques, i.e., FTIR and UV-visible spectroscopy, were employed for functional identification and optical absorption of the poly(*o*-anisidine)/BaSO4 nanocomposites. The FTIR data revealed the significant interaction between POA and BaSO4, as well as the good absorption behavior of the UV-visible spectra. The conducting properties were controllable by varying the load percentage of the BaSO4 filler. Furthermore, different bacterial strains, i.e., *Pseudomonas aeruginosa* (Gram-negative) and *Staphylococcus aureus* (Gram-positive), were used to evaluate the antibacterial activity of the POA/BaSO4 nanocomposites. The largest zones of inhibition 0.8 and 0.9 mm were reached using 7% and 10% for *Staphylococcus aureus* and *Pseudomonas aeruginosa*, respectively.

**Keywords:** nanocomposites; antibacterial; electrical conductivity; BaSO4; polymerization
