The FTIR spectra of both PA-ZK and BS-S1X bacterial strains SS304 surface were obtained as shown in Figure . The reflectance signatures originated at 400-900 cm -1 were associated with the presence of metal oxides i.e. Fe, Ni, Cr oxides that can be expected due to the release of metallic ions from the surface of SS304 samples. The presence of alcoholic and ether groups was evident from the appearance of peaks at 900-1,400 cm -1 . The peaks observed at ∼1,550 cm -1 and ∼1,650 cm -1 corresponded to the amide II and amide I groups, respectively. Carboxylic acid and NH/OH functional groups were represented by the peaks observed at 2,400 cm -1 and 3,400-3,900 cm -1 , respectively. The origin of these peaks was associated with the organic species in the EPS (in the biofilm) that could remain on the surface of SS304 after exposure to bacterial strains even after surface cleaning.