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A delegation from the Université de Namur took part in an exploratory mission to the Université Cheikh Anta Diop (UCAD) in Dakar, Senegal. The aim: to discover the research carried out in the field, meet UCAD researchers and initiate future collaborations between the two institutions.

AbstractFrequently touched surfaces (fomites) serve as reservoirs for pathogens, including bacteria and viruses, and act as vectors for contact-mediated transmission. They contribute to the spread of healthcare-associated infections and pose an increased risk during epidemic outbreaks, as highlighted by the COVID-19 pandemic. This thesis focuses on the development of antimicrobial coatings that release silver (Ag) and copper (Cu), deposited by magnetron sputtering. Three coating matrices were investigated: hydrogenated amorphous carbon with or without chromium (a-C:H and Cr/CrN/a-CrC:H) and titanium aluminum nitride (TiAlN).Antibacterial performance was evaluated against Staphylococcus aureus and Escherichia coli. To assess long-term efficacy, the antibacterial properties of the coatings were investigated through successive bacterial exposure cycles. Antiviral activity was evaluated against porcine respiratory coronavirus (PRCV), a member of the Orthocoronavirinae subfamily to which SARS-CoV-2 also belongs. For this purpose, a rapid, high-throughput antiviral screening assay was developed. This innovative method represents a promising approach for the standardized evaluation of antiviral surfaces. In addition to antimicrobial activity, the coatings were required to exhibit adequate mechanical properties and an attractive black appearance suitable for high-touch surfaces.The combination of Ag and Cu exhibited a synergistic effect, enhancing antimicrobial activity and broadening the spectrum of targeted pathogens. Optimization led to a TiAlN coating containing 0.9 at.% Ag and 1.7 at.% Cu, which provided the best balance between mechanical, antibacterial, and antiviral performance. Tribological wear tests confirmed that its antimicrobial efficacy was maintained for up to two years. Prospects for the further development and scientific validation of this prototype are discussed.JuryProf. Benoît MUYLKENS (UNamur), ChairProf. Stéphane LUCAS (UNamur), SecretaryProf. Jean-Michel DOGNÉ (UNamur)Prof. Philippe STEYER (INSA Lyon, University of Lyon)Dr. Sébastien PENNINCKX (UNamur)Dr. Emile HAYE (Innovative Coating Solutions)