title: Rapid and selective nitroxyl (HNO) trapping by phosphines: kinetics and new aqueous ligations for HNO detection and quantitation.
abstract: Recent studies distinguish the biological and pharmacological effects of nitroxyl (HNO) from its oxidized/deprotonated product nitric oxide (·NO), but the lack of HNO detection methods limits the understanding its in vivo mechanisms and the identification of endogenous sources. We previously demonstrated that reaction of HNO with triarylphosphines provides aza-ylides and HNO-derived amides, which may serve as stable HNO biomarkers. We now report a kinetic analysis for the trapping of HNO by phosphines, ligations of enzyme-generated HNO, and compatibility studies illustrating the selectivity of phosphines for HNO over other physiologically relevant nitrogen oxides. Quantification of HNO using phosphines is demonstrated using an HPLC-based assay and ligations of phosphine carbamates generate HNO-derived ureas. These results further demonstrate the potential of phosphine probes for reliable biological detection and quantification of HNO.
authors.affiliation: Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, USA.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Reisz
authors.forename: Charles N
authors.initials: CN
authors.lastname: Zink
authors.forename: S Bruce
authors.initials: SB
authors.lastname: King
mesh_terms: D002851:Chromatography, High Pressure Liquid; D007700:Kinetics; D015394:Molecular Structure; D009589:Nitrogen Oxides / Q000032:analysis*; D010720:Phosphines / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D009589:Nitrogen Oxides; D010720:Phosphines; D014867:Water; C039900:nitroxyl