Method of purifying 8-isoprostane

摘要

A method of purifying 8-isoprostane is provided that includes a step of contacting a liquid sample containing 8-isoprostane with an ion exchange support having a quaternary ammonium salt immobilized thereon such that 8-isoprostane in the liquid sample is retained on the ion exchange support and a step of eluting 8-isoprostane from the ion exchange support using a first eluent containing a water-soluble organic solvent and water as main components; wherein the ion exchange support has a tetraalkylammonium salt represented by Formula (1) below immobilized thereon, and
wherein, in Formula (1), R 1 , R 2 , and R 3 are alkyl groups having 1 to 6 carbon atoms, n is 1 to 5, B is a resin substrate or silica gel, and X - is a chloride ion.