Fig. 2.

Direct infusion ESI-MS analysis of native and HNE-modified HSA. Mass spectra of HSA recorded in a mass range between m/z 1400 and 1500. A) Native HSA shows sharp intense peaks referred to the charge ions 47 + , 46 + and 45 + ; the deconvoluted spectrum reports a MW 66,455 Da (H). When HSA is reacted with HNE at increasing molar ratios 1:1 (B), 1:5 (C), 1:10 (D), additional peaks relative to HNE adducts appear. At higher molar ratios 1:100 (E), 1:200 (F) and 1:1000 (G) the MS spectra lose resolution and become flat due to the presence of multiple adducts. H) Deconvoluted spectra showing the MS of HSA and protein adducts. MS spectra relative to HSA incubated with HNE at 1:100 M ratio and higher cannot be deconvoluted due to the extent of modification.