Development of new types of antimicrobial coatings is of utmost importance due to increasing problems with pathogen transmission from various infectious surfaces to human beings. In this study, new types of highly potent antimicrobial polyurethane composite films encapsulated by hydrophobic riboflavin-based carbon polymer dots are presented. Detailed structural, optical, antimicrobial, and cytotoxic investigations of these composites were conducted. Low-power blue light triggered the composites to eradicate Escherichia coli in 30 min, whereas the same effect toward Staphylococcus aureus was reached after 60 min. These composites also show low toxicity against MRC-5 cells. In this way, RF-CPD composites can be used for sterilization of highly touched objects in the healthcare industry.

Centre for Advanced Materials Application Slovak Academy of Sciences Dúbravská Cesta 9 84511 Bratislava Slovakia

Department of Multilayers and Nanostructures Institute of Physics Slovak Academy of Sciences Dúbravská Cestá 9 84541 Bratislava Slovakia

Department of Physical Electronics Faculty of Science Masaryk University Kotlářská 2 611 37 Brno Czech Republic

Faculty of Biology University of Belgrade Studentski trg 16 11000 Belgrade Serbia

Institute of Materials and Machine Mechanics Slovak Academy of Sciences Dúbravská Cestá 9 6319 84513 Bratislava Slovakia

Institute of Molecular Genetics and Genetic Engineering University of Belgrade Vojvode Stepe 444a 11042 Belgrade Serbia

J Heyrovsky Institute of Physical Chemistry Academy of Sciences of the Czech Republic Dolejškova 3 182 23 Praha Czech Republic

Polymer Institute Slovak Academy of Sciences Dúbravská Cestá 9 84541 Bratislava Slovakia

Serbian Academy of Sciences and Arts Knez Mihailova 35 11000 Belgrade Serbia

Vinča Institute of Nuclear Sciences National Institute of the Republic of Serbia University of Belgrade 11000 Belgrade Serbia

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