One-electron degradation of 5α-OOH with concurrent formation of 7α/7β-OOH in unilamellar POPC/Ch/5α-OOH (100/75/5 by mol) liposomes during incubation with ascorbate (1 mM) and Fe(HQ)3 (1 µM) in Chelexed PBS at 37°C. (A) HPLC-EC(Hg) profiles of lipid extracts after 0 min (a), 5 min (b), and 30 min (c). (B) 5α-OOH (⬤,○) and 7α/7β-OOH (π,ρ) levels over time with Fe(HQ)3 present (⬤, π) or absent (○,ρ). Reproduced from Korytowski et al. (2000) Chem. Res. Toxicol. 13:1265 (with permission).