title: High-performance liquid chromatography with post-column 2,2'-diphenyl-1-picrylhydrazyl radical scavenging assay: methodological considerations and application to complex samples.
abstract: An improved post-column 2,2'-diphenyl-1-picrylhydrazyl (DPPH*) radical scavenging assay for the screening of antioxidants in complex matrices was developed. Experimental parameters believed to be influential to DPPH* response were studied in a univariate approach. Optimum conditions were found to be: 5 x 10(-5) M DPPH* reagent prepared in a 75% methanol: 25% 40 mM citric acid-sodium citrate buffer (pH 6) solution, degassed with nitrogen; reaction coil of 2 m x 0.25 mm i.d. PEEK tubing; detection at 521 nm; analysis at room temperature. The analytical utility of this protocol was evaluated by screening for antioxidants in thyme and green tea, in comparison with two commonly employed methodologies.
authors: School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3217, Australia.
authors: Geoffrey P
authors: GP
authors: McDermott
authors: Laura K
authors: LK
authors: Noonan
authors: Mariam
authors: M
authors: Mnatsakanyan
authors: R Andrew
authors: RA
authors: Shalliker
authors: Xavier A
authors: XA
authors: Conlan
authors: Neil W
authors: NW
authors: Barnett
authors: Paul S
authors: PS
authors: Francis
mesh_terms: D001713:Biphenyl Compounds / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D016166:Free Radical Scavengers / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D010851:Picrates / Q000032:analysis*; D013662:Tea / Q000737:chemistry; D013696:Temperature; D046930:Thymus Plant / Q000737:chemistry
chemical_list: D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D010851:Picrates; D013662:Tea; C004931:1,1-diphenyl-2-picrylhydrazyl