Abstract | OBJECTIVES: METHODS: RESULTS: Validation showed for allopurinol lower and upper limits of quantification of 0.5 and 10mg/L and for oxipurinol 1 and 40 mg/L, respectively. The assay was linear over the concentration range of 0.5-10mg/L ( allopurinol) and 1-40 mg/L ( oxipurinol). Intra- and inter-day precision showed coefficients of variation <15% over the complete concentration range; accuracy was within 5% for allopurinol and oxipurinol. Endogenous purine-like compounds were separated from allopurinol, oxipurinol and aciclovir with a resolution factor >1.5. Exogenous purine-like compounds and co-medication frequently used by gout patients did not hinder the analysis due to the dichloromethane washing step or to low UV-absorpion at 253 nm. Serum levels of 66 patients prescribed allopurinol 300 mg/day were determined using this HPLC-UV method. Measured serum allopurinol and oxipurinol concentrations in clinical practice showed large variability with a range of <0.5-4.3 mg/L for allopurinol and <1.0-39.2 mg/L for oxipurinol, respectively. CONCLUSION: We developed an easy-to-operate and validated HPLC-UV method for the quantification of allopurinol and oxipurinol in human serum. This method was proven to be valid for samples of gout patients frequently using concomitant medications.
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Authors | Mattheus K Reinders, Lars C Nijdam, Eric N van Roon, Kris L L Movig, Tim L Th A Jansen, Mart A F J van de Laar, Jacobus R B J Brouwers |
Journal | Journal of pharmaceutical and biomedical analysis
(J Pharm Biomed Anal)
Vol. 45
Issue 2
Pg. 312-7
(Oct 18 2007)
ISSN: 0731-7085 [Print] England |
PMID | 17890037
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- Sodium Acetate
- Allopurinol
- Oxypurinol
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Topics |
- Adult
- Aged
- Aged, 80 and over
- Allopurinol
(blood)
- Chromatography, High Pressure Liquid
(methods)
- Drug Stability
- Female
- Humans
- Hydrogen-Ion Concentration
- Male
- Middle Aged
- Oxypurinol
(blood)
- Reference Standards
- Reproducibility of Results
- Sodium Acetate
(chemistry)
- Spectrophotometry, Ultraviolet
(methods)
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