Semi-automatic liquid chromatographic analysis of pamidronate in urine after derivatization with 1-naphthylisothiocyanate.
An existing sensitive chromatographic assay for pamidronate in urine has considerably been automated. Using the same sample processor, the solid-phase extraction (SPE) was automated separately from the derivatization with 1-naphthylisothiocyanate, the two-fold ion-pair liquid-liquid-extraction and the treatment with hydrogen peroxide for the 2-20 ng/ml concentration range. The automatic procedure was preceded by a triple calcium precipitation and interrupted by evaporation of the SPE eluate under nitrogen. For the 0.5-5 microg/ml concentration range one automatic sequence was used by avoiding evaporation during the sample treatment. In addition to the labour-saving of the semi-automatic procedure, the daily sample-throughput was improved compared to the existing manual assay. Further, the validation showed marginal improvements in the precision, accuracy and lower limit of quantification.
Sparidans
R W
RW
Leiden University Medical Center, Department of Clinical Pharmacy and Toxicology, The Netherlands. r.w.sparidans@pharm.uu.nl
den Hartigh
J
J
Cremers
S
S
Beijnen
J H
JH
Vermeij
P
P
D015058:1-Naphthylisothiocyanate / Q000737:chemistry; D001331:Automation; D002853:Chromatography, Liquid / Q000379:methods*; D004164:Diphosphonates / Q000737:chemistry / Q000493:pharmacokinetics / Q000652:urine*; D006801:Humans; D007202:Indicators and Reagents / Q000737:chemistry; D000077268:Pamidronate; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D004164:Diphosphonates; D007202:Indicators and Reagents; D015058:1-Naphthylisothiocyanate; D000077268:Pamidronate