Fig. 3.

Oxidation levels within the UHMWPE components characterized using FTIR microspectroscopy (MicroFTIR) (AutoImage FTIR Microscope System, Perkin–Elmer). Spectra were run in transmission mode, with a 4 cm1 resolution and 16 scans per spectrum. In preparation for FTIR analysis, the UHMWPE components were sectioned using a microtome into 180-m-thick specimens. FTIR microscopy spectra of EtO sterilized acetabular liner after 11 years in vivo service and removed for aseptic loosening, shows the presence of esters and acids at a minimum oxidation level (0.02 A) and after NO treatment, any nitrate absorption at 1650–1620 cm–1 is visible (means no oxidation) (Fig. 3).