title: Optimization and validation of an ion-pair RP-HPLC-UV method for the determination of total free iodine in rabbit plasma: application to a pharmacokinetic study.
abstract: An ion-pair reverse-phase high performance liquid chromatographic method with UV-vis detection has been developed for the determination of total free iodine in rabbit plasma after vaginal administration of povidone-iodine (PVP-I). Sample preparation was done by protein precipitation with acetonitrile in 96-well format and aspirin was used as the internal standard. The 100 microL sodium thiosulfate solution (5 g L(-1)) was added to 100 microL plasma sample before protein precipitation, to convert the total free iodine in plasma to iodide (I(-)). Separation was performed on a C(18) column (200 x 4.6 mm i.d., 5 microm). The mobile phase consisting of a mixture of water phase (containing 10 mmol L(-1) 18-crown-6 ether, 5 mmol L(-1) octylamine and 5 mmol L(-1) sodium dihydrogen phosphate, pH adjusted to 6.0 with phosphoric acid) and acetonitrile in the ratio 70:30 (v/v) was delivered isocraticly at a flow rate of 1.0 mL min(-1). The method was sensitive with a lower limit of quantification of 0.005 microg mL(-1), with good linearity (r(2) > 0.9990) over the linear range of 0.005-2 microg mL(-1). All the validation data, such as linearity, accuracy and precision, were within the required limits. The method was successfully applied to study the pharmacokinetic of PVP-I in rabbits after vaginal administration.
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Shanghai 200433, People's Republic of China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Cui
authors.forename: Jun
authors.initials: J
authors.lastname: Wen
authors.forename: Tingting
authors.initials: T
authors.lastname: Zhou
authors.forename: Shuowen
authors.initials: S
authors.lastname: Wang
authors.forename: Guorong
authors.initials: G
authors.lastname: Fan
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000588:Amines / Q000737:chemistry; D000818:Animals; D001241:Aspirin / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase / Q000379:methods*; D043844:Crown Ethers / Q000737:chemistry; D005260:Female; D007455:Iodine / Q000097:blood* / Q000493:pharmacokinetics* / Q000592:standards; D010710:Phosphates / Q000737:chemistry; D011206:Povidone-Iodine / Q000008:administration & dosage; D011817:Rabbits; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012996:Solutions / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D013885:Thiosulfates / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D000097:Acetonitriles; D000588:Amines; D043844:Crown Ethers; D010710:Phosphates; D012996:Solutions; D013885:Thiosulfates; D014867:Water; C015762:18-crown-6; D011206:Povidone-Iodine; D007455:Iodine; C017717:sodium thiosulfate; D001241:Aspirin; C018279:sodium phosphate; C008699:octylamine; C032159:acetonitrile