Methodological approach of antibacterial surfaces characterization

Abstract

The surface biocontamination is a very widespread phenomenon in the food industries, medical appliances...
This biofouling can alter the products, leading to economic losses linked or not to health problems. Stainless
steel is extensively used in the above mentioned markets because of its good cleanability, high corrosion
resistance, stability, inertia under most circumstances.
Nevertheless, in material research, an important way of investigation is the elaboration of material able to kill
microorganisms that are in contact with or limit their proliferation. The development of such surfaces requires
robust and standardized methods to quantify the antimicrobial activity of those materials. Only few standards
are available such as JIS Z2801 which is based on a culture method. This standard was assessed and
compared to alternative methods. The study was carried out using stainless steel as the reference material,
“antimicrobial” materials, and two bacterial species: E. coli and S. aureus.
Because viability is not easily defined with a single physiological or morphological parameter, the obtained
results show the possible overestimation of the material antimicrobial activity with cultivation methods such
as the JIS Z2801 standard. Thereby, to assess the antibacterial activity of materials, it is preferable to combine
different methodologies, such as culture and in situ detection.