Preparation And Properties Of Superhydrophobic Antibacterial Surface Synergistic Enhanced By Photostimulation

The bacterial adhesion on the surface of materials and its subsequent infections have become a major threat to human health.The superhydrophobic property of the material can reduce the contact area between the surface and bacteria,and prevent the adhesion behavior of bacteria at the source,thus avoiding the occurrence of bacterial infection.However,the superhydrophobic surfaces lack long-term resistance to bacterial adhesion.With time,the surface air layer will gradually disappear,and the adhesion of bacteria is inevitable.Therefore,it is urgent to develop superhydrophobic surfaces with bactericidal activity to eliminate the bacteria adhering to the surface and maintain sustainable antibacterial function on the materials.This paper combined the superhydrophobic property of anti-bacterial adhesion with photothermal/photodynamic and mechanical sterilization to kill bacteria,and developed multifunctional antibacterial surfaces based on superhydrophobicity.The main research works are as follows:1.Medical protective clothing made of cotton fabric has attracted wide attention due to its good air permeability and comfortable softness.However,cotton fabric is prone to moisture and can become a breeding ground for bacteria.Therefore,achieving safe and sustainable antibacterial properties through surface functional design of cotton fabric has become a hot topic in current research.In this work,a superhydrophobic cotton fabric surface with the photothermal antibacterial effect was developed.Firstly,the surface was given a certain rough structure by the self-assembly of silica dioxide and polypyrrole,and then the superhydrophobic cotton fabric（Rf-CFS-PPY）with low surface energy was obtained via the chemical vapor deposition process of trichloro（1H,1H,2H,2H-heptadecafluorodecyl）silane.The superhydrophobic properties of Rf-CFS-PPY are very stable and can withstand a variety of extreme conditions,including strong acid immersion,sandpaper rubbing,and ultrasonic treatment.The Rf-CFS-PPY not only has excellent self-cleaning and blood stain resistance,but also can resist daily liquid pollution and increase the service life of the cotton fabric.More importantly,owing to the synergistic superhydrophobic bacterial repellency and photothermal antibacterial properties,Rf-CFS-PPY shows extremely high antibacterial performance against both Staphylococcus aureus and Escherichia coli.The cotton fabric also shows excellent blood compatibility and has potential application value in medical protective fabric.2.Bacterial invasion and proliferation on various surfaces pose a serious threat to public health worldwide.Conventional antibacterial strategies that mainly rely on bactericides exhibit high bacteria-killing efficiency but might trigger the well-known risk of antibiotic resistance.Here,we report a superhydrophobic mechano-bactericidal surface with photodynamically enhanced antibacterial capability.First,bioinspired nanopillars with polycarbonate as the bulk material were replicated from anodized alumina oxide templates via a simple hot-pressing molding method.Subsequently,chlorin e6 was introduced onto the nanopillar-patterned surface using a facile bovine serum albumin phase-transition method,which was then perfluorinated to render the surface superhydrophobic.Benefiting from its strong liquid super-repellency and photodynamically enhanced mechano-bactericidal properties,the superhydrophobic nanopillar-patterned surface exhibits 100%antibacterial efficiency after 30 min visible light irradiation(650 nm,20 m W cm^-2).More strikingly,the surface exhibited impressive long-lasting antimicrobial performance,maintaining a very high bactericidal efficiency（≥99%）even after 10 cycles of bacterial contamination tests.Also,the superhydrophobic nanopillar-patterned surface displays good hemocompatibility with a hemolysis rate below 5%.Overall,this work offers a new method for significantly improving the antibacterial efficiency of structural antimicrobial surfaces without involving any bactericidal agents,and this functional surface shows great potential in the field of advanced medical materials.