Antibacterial nanotechnology and thin films on various substrates and flexible textiles

Abstract text (incl. figure legends and references)

Antibiotics are powerful drugs that are used to treat bacterial infections, and they work by targeting their cell walls or protein synthesis machinery, and interfering with their normal function. However, over- and misuse of these drugs lead to the development of antibiotic-resistant bacteria. Antibiotic resistance is a major issue in modern medicine, and has the potential to impact the health of millions of people around the world. Due to the high cost in the development of new antibiotics, novel antibacterial materials or thin films based on other principles have to be developed to address.

Inspired from the antibacterial effect of the nanostructures presented on certain insect wings such as those on dragonfly and cicade, biomimic silicon nanowires (SiNWs) arrays have been proposed as novel anti-microbes surfaces. It was demonstrated that certain SiNWs show high bacteria killing efficiency measured by confocal laser scanning microscopy (Fig. 1), and the suggested mechanisms include mechanical piercing, immobilization of the bacteria, however, there are still adverse results which do not support such suggestions, we believe that more work have to be done to clarify the exact mechanism of the antibacterial effect of the SiNWs. Large area antibacterial SiNWs can be realized on silicon thin films deposited on various substrates and metal foils by scalable wet chemical etching processes.

Furthermore, metals such as silver and copper have well-known antimicrobial and antiviral effects, and we demonstrated also scalable electroless plating processes, for the coating of silver or copper thin films on various substrates, respectively, for examples, on textiles, papers and woods (Fig. 2). This opens application in the fields of hospital furnishings, operating room, patient care, face masks, and many more.