title: High-performance liquid chromatographic determination of morphine and its 3- and 6-glucuronide metabolites: improvements to the method and application to stability studies.
abstract: Improvements to previously reported methods for the determination of morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) in human plasma are described. The improved methods involve the use of a solid-phase extraction cartridge and a chromatographic system which uses paired-ion reversed-phase high-performance liquid chromatography with a radially compressed column. Only one cartridge is used to prepare each sample for chromatography and each cartridge may be used for at least fourteen 1-ml plasma samples. The recovery is greater than 85%. The improvements to the method of sample pretreatment and in the chromatographic conditions have allowed determination of morphine, M3G and M6G in human plasma down to 13.3 nmol/l (coefficient of variation = 9.3%), 108 nmol/l (6.6%) and 41 nmol/l (6.7%), respectively, using ultraviolet detection alone. It was shown that all three compounds were stable in plasma for up to 101 weeks when stored at -20 degrees C.
authors.affiliation: School of Pharmacy, South Australian Institute of Technology, North Tce, Adelaide.
authors.forename: R W
authors.initials: RW
authors.lastname: Milne
authors.forename: R L
authors.initials: RL
authors.lastname: Nation
authors.forename: G D
authors.initials: GD
authors.lastname: Reynolds
authors.forename: A A
authors.initials: AA
authors.lastname: Somogyi
authors.forename: J T
authors.initials: JT
authors.lastname: Van Crugten
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005965:Glucuronates / Q000097:blood*; D006801:Humans; D009020:Morphine / Q000097:blood* / Q000493:pharmacokinetics
chemical_list: D005965:Glucuronates; D009020:Morphine