– 4-hydroxy Nonenal is a lipid peroxidation product derived from oxidized ω-6 polyunsaturated fatty acids such as arachidonic acid and linoleic acid. [1] [2] It exhibits various biological activities such as cytotoxicity, growth inhibiting activity, genotoxicity, and chemotactic activity and has been widely used as a marker of lipid peroxidation.[1][2][3] 4-oxo-2-Nonenal is a more recently identified product of lipid peroxidation.[4][5][6] It actively modifies histidine and lysine residues on proteins and causes protein cross-linking. [7][8] 4-oxo-2-Nonenal also modifies 2′-deoxyguanosine, further implicating lipid peroxidation in mutagenesis and carcinogenesis.[4]