Anti-biofilm efficiency of 120 MeV Fe+9 SHI-irradiated polyimide film

Abstract

ABSTRACT Polyimide (PI) films were irradiated by 120 MeV iron (Fe+9) ions and variations in its optical, chemical, surface morphology and anti-bacterial properties were studied. UV-Visible spectroscopic results showed the decrease in the optical band gap of PI after irradiation due to the chain scission mainly at the carbonyl group which is corroborated by Fourier Transform Infrared spectroscopic results. The scanning electron microscopic results showed the surface roughening, surface structure broken and micro-porous formation in PI after irradiation. These results are also corroborated by the decrease in contact angle as studied by the contact angle measurement. PI films irradiated by 120 MeV Fe+9 ions showed increased anti-biofilm efficacy against the human pathogen, Salmonella typhi. In addition to this, the morphological changes were also observed due to the stress of Fe-irradiated PI. Biofilm formation was inhibited ≈ 35% at 1 × 1011 ion/cm2 and 80% at 5 × 1012 ion/cm2 in irradiated PI films. Thus, surface modification of PI films help in the inhibition of biofilm formation. Highlights Polyimide (PI) films were irradiated by 120 MeV Fe+9 ions. Optical band gap of PI decreased after ion irradiation. Surface roughening and micro-pores formation in PI after ion irradiation. Surface modification of PI films helps in the inhibition of bio-film formation.