ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Batch synthesis of polyoxometalate-based phosphonium compounds by one-step room-temperature mechanochemical process, and their morphology-dependent antibacterial activities

Shuyu Hu, Cuncheng Ma, Fangyi Zhan, Yali Cao, Pengfei Hu, and Qiang Zhen

Xiangya School of Medicine, Central South University, Changsha, People’s Republic of China

E-mail: hpf-hqx@shu.edu.cn

Abstract: Based on the Keggin-type polyoxometalate and quaternary phosphonium salt, the (MePh₃P)_n-POM_Keggin compounds were synthesized via one-step mechanochemical process at room temperature. It showed the advantages of convenient operation, lower cost, less pollution, and mass production. Wonderfully, the morphology of compounds presented a strong dependence on the number of crystal water in the source heteropoly acids. A hypothesis of ‘semi-solid nonlocalized waters’ was brought to discuss the formation mechanism of polyhedrons. Antibacterial experiments indicate that the samples have good antibacterial activities, which resulted from the increase of the positive electrical charge of the phosphonium cation caused by the polarization by POM groups. Additionally, a formula of inhibitory zone per unit surface area was designed to more precisely evaluate the antibacterial activity of the materials. The calculation result indicated that the polyhedral particles give a higher surface antibacterial activity than the grain powder. This work developed an alternative synthesis method for composites from a new perspective, and will promote the research of new type of antibacterial agent.

Keywords: Mechanochemical processing, Polyoxometalates, Phosphonium, Bacteriostasis

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-016-0124-1

Chemical Papers 71 (7) 1323–1329 (2017)