Physiochemical characterization and antimicrobial evaluation of phenylthiourea–formaldehyde polymer (PTF) based polymeric ligand and its polymer metal complexes Tansir Ahamad, Saad M. Alshehri ⇑ Department of Chemistry, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia highlights " A novel polymeric ligand has been synthesized via polycondensation of phenylthiourea with formaldehyde. " The polymer metal complexes were prepared with Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) ions. " All the polymers have been characterized by elemental, spectral and thermogravimetric analyses. " Antimicrobial activities were performed against several bacteria and fungi using agar well diffusion method. graphical abstract article info Article history: Received 18 September 2012 Received in revised form 22 January 2013 Accepted 23 January 2013 Available online 8 February 2013 Keywords: Phenylthiourea Thermogravimetric analysis FTIR Antimicrobial activity abstract Phenylthiourea–formaldehyde polymer (PTF) has been synthesized via polycondensation of phenylthio- urea and formaldehyde in basic medium and its corresponding metal complexes [PTF-M(II)] were prepared with Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) ions. The synthesized polymers have been characterized by ele- mental analysis, magnetic susceptibility, UV–visible, FT-IR, 1 H NMR, 13 C NMR, ESR spectroscopy and ther- mogravimetric analysis (TGA). Elemental analysis, electronic spectra and magnetic moment measurement indicate that PTF-Mn(II), PTF-Co(II) and PTF-Ni(II) show octahedral geometry, while PTF-Cu(II) and PTF- Zn(II) show square planar and tetrahedral geometry, respectively. The results of TGA ascribed that all the PTF-M(II) showed better heat-resistance properties than PTF resin. In vitro antimicrobial activities were performed against several bacteria and fungi using agar well diffusion method. The results of microbial activity were compared with Kanamycin and Miconazole as standard antibiotics for antibacterial and anti- fungal activities respectively. Ó 2013 Elsevier B.V. All rights reserved. Introduction Polymer metal complexes are a new and interesting class of materials that combine some of the mechanical properties of the organic polymer and some of those of the metal ions. A large num- ber of such polymers have been synthesized and studied and have been found to be of interest because of their biological applications such as antitumor, antibacterial, antiviral and antifungal agents [1– 4]. The biological activities of the polymeric ligands are considered due to their ability to form polymer metal complexes with metal ions. The biological activity of polymer metal complexes is different 1386-1425/$ - see front matter Ó 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.saa.2013.01.053 ⇑ Corresponding author. Tel.: +966 1 4675971; fax: +966 1 4674018. E-mail address: alshehri@ksu.edu.sa (S.M. Alshehri). Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 108 (2013) 26–31 Contents lists available at SciVerse ScienceDirect Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy journal homepage: www.elsevier.com/locate/saa