Preparation of silicon-modified antimicrobial polyethylene endotracheal tubes.

Antimicrobial coating of polyethylene endotracheal tubes (PE ETTs) has proven to be an effective method to prevent endoluminal biofilm formation. A transparent silicon-modified antimicrobial PE ETT was obtained by coating PE with a SiO2 /γ-methacryloxypropyl trimethoxy silane (KH-570)/methyltriethoxysilane (MTES)/Ag-SiO2 solution prepared by chemically mixing Ag-SiO2 with SiO2 /KH-570/MTES in solution via a dip-coating method, with tetraethyl orthosilicate (TEOS) as the inorganic silicon source, followed by drying. All the films were characterized by various techniques, including the pencil hardness test, infrared spectroscopy, scanning electron microscopy, UV-vis analysis, and inductively coupled plasma mass spectrometry (ICP-MS). The results indicated that the TEOS/KH-570/MTES/Ag-SiO2 (15:6:1:0.6-1.0) films, which exhibited simple in-solution film formation on PE ETTs, had a homogeneous morphology, high transmittance above 87%, high hardness of 5H and strong adhesion to the tubes. The concentration of Ag+ ion dissolved out from the antibacterial coating is very low in ICP-MS results. The antibacterial test results show that the antibacterial coatings have excellent antibacterial property with antibacterial ratio up to 93.5% when Ag-SiO2 content is 2.6%. In pyrogen test and hemolytic test, the body temperature of rabbits rise 0.03°c for 3 h after inserting antibacterial PE ETT, and the hemolytic ratio is 0.7512%, which conform to the requirements of biomedical material. The results preliminarily proved that the antibacterial materials could be a good candidate of medical catheter material application or medical device surface coating materials.