Title: Titanium(IV) oxo-complexes with {Ti4O2} core, their photocatalytic and antimicrobial properties

Abstract

The current epidemiological situation in the world has revealed that microorganisms are still a huge threat to human life and health. This is due to the fact that most of the microorganisms have become resistant to the antibiotics and antimicrobial agents used so far. For this reason, there is an intensive search for new compounds, which show adequate microbiocidal activity and may be an alternative to those currently used. A new solution may be titanium(IV) oxo-complexes (TOCs), which can prevent the spread of bacteria. The aim of our researches is synthesis of TOCs consisted of Ti4O2 cores as a result of titanium(IV) isobutoxide reaction with 4-aminobenzoic acid (1) or 9-fluorenecarboxylic acid (2). Isolated TOCs have been dispersed in polycaprolactone (PCL) matrix, forming in this way PCL + TOCs composite system. The obtained materials can be used as antibacterial surfaces in medical instruments and public places. Titanium(IV) oxo-complexes were syntesized under an inert atmosphere, by mixing titanium(IV) isobutoxide with a carboxylic acid (1 or 2) in an organic solvent. Composite materials were dispersed (5 wt.% or 20 wt.%) in a polymer matrix. The obtained composites were examined by IR and Raman spectroscopy, Raman mapping and also subjected to thermal analysis by TG and DSC methods. SEM EDX analysis was also performed, which confirmed the presence of TOCs in the polymer matrix. The photocatalytic activity was investigated by observing the degradation of methylene blue (MB) under VIS light. Microbiological tests were carried out for the following bacteria: Escherichia coli, Staphylococcus ureus and Candida albicans yeasts. The photocatalytic activity is related to the used TOCs concentration. Better results are obtained for a concentration of 20%, but in microbiological tests, a lower concentration does not affect the obtained results so much. Obtained compounds can be used as a antibacterial agents in the future.

Biography

Barbara Kubiak graduated in cosmetic chemistry and forensic chemistry. Since 2019 he is a PhD student at the Department of Inorganic and Coordination Chemistry at the Nicolaus Copernicus University in Toruń. He deals with the preparation of titanium oxo-complexes as well as the study of their properties, primarily photocatalytic and microbiological.