Evaluation of TiO2 and Ag-TiO2, CuO-TiO2 composite films for self-disinfection activity

Steele, KC

Abstract

The removal or killing of microorganisms on surfaces is of concern in the health
care setting, food preparation areas and general work environment. The use of
TiO2 photosterilisation has been proposed as an alternative to chemical
disinfection of surfaces as a means to reduce the need for increasingly
concentrated and aggressive chemicals necessary to kill disinfectant-resistant
organisms.
The objective of this research was to evaluate the ability of photocatalytic
oxidation to reduce bacterial and viral contaminants on surfaces coated with
TiOa and Ag-TiC^, TiO2-Ag, Cu-TiC^, TiO2-Cu. There are no British Standards
that cover evaluation of such surfaces. A method for evaluation of photocatalytic
surfaces was therefore developed from BS EN 13697:2001 and used to
evaluate the activities of a variety of catalytic surfaces coated with TiO2, Ag and
Cu and multi-layers of Ag-TiO2,TiO2-Ag, Cu-TiO2,TiO2-Cu. The antimicrobial
activities were found to be dependent on the nature of the coating. Highest
killing activities were obtained with Ag and Cu alone but combinations of Ag or
Cu with TiO2were more active than TiO2 alone and also retained some self-
cleaning activity. The results showed that the developed method was adaptable
for determination of the antimicrobial activity of coatings with a wide range of
activities producing 100% killing of Escherichia coll in times from 3 min up to 4
h. The results showed that it was possible to produce self cleaning self
disinfecting surfaces and that surfaces with TiO2 on top, although having
reduced activity compared to Ag or Cu, were durable and may have
applications in the prevention of transmission of infections on surfaces in a wide
range of applications.

• Thesis Type: Thesis
• Deposit Date: Oct 3, 2012
• Additional Information: Access Information : At the author’s request this item is not available. You may be able to access the hard copy by visiting the University of Salford Library
• Award Date: Jan 1, 2009