title: [Determination of irisquinone by single sweep oscillopolarography].
abstract: OBJECTIVE
  To propose a polarographic method for the determination of irisquinone.
  
  
  METHODS
  A reduction wave of irisquinone was recorded by single sweep oscillopolarography.
  
  
  RESULTS
  In 8.0 x 10(-3) mol.L-1 Na2B4O7-1.6 x 10(-2) mol.L-1 KH2PO4 (pH 7.7) supporting electrolyte, a redution wave of irisquinone with peak potential -1.23 V (vs SCE) achieved high sensitivity. The 2nd-order derivative peak current of the reduction wave was proportional to irisquinone concentration in the range of 1.5 x 10(-7)-5.2 x 10(-6) mol.L-1 (gamma = 0.9992, n = 9). The detection limit was 6.0 x 10(-8) mol.L-1. Relative standard deviation (RSD) was 0.87% by performing 13 independent measurements on 2.0 x 10(-6) mol.L-1 irisquinone.
  
  
  CONCLUSIONS
  The proposed method was sensitive, simple, rapid, and can be applied to the determination of irisquinone in raw medicine and capsule.
authors.affiliation: Institute of Analytical Science, Northwest University, Xi'an 710069, China.
authors.forename: Ping
authors.initials: P
authors.lastname: He
authors.forename: Jun-feng
authors.initials: JF
authors.lastname: Song
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000032:analysis* / Q000737:chemistry; D016227:Benzoquinones / Q000008:administration & dosage / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D002214:Capsules; D004563:Electrochemistry; D007498:Iris / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D011048:Polarography; D012639:Seeds / Q000737:chemistry
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D016227:Benzoquinones; D002214:Capsules; C032941:irisquinone