Identification of factors limiting the accurate measurement of plasma D-penicillamine in rheumatoid arthritis patients.
Free and total reduced concentrations of D-penicillamine have been measured in the plasma of rheumatoid arthritis patients by HPLC and electro-chemical detection. A reverse-phase ion-pair separation in conjunction with a dual porous graphite electrode satisfied the requirements of robustness, sensitivity, selectivity and suitable retention time. Plasma levels measured between 1.5 and 3 h after an oral dose, were less than 0.3 to 57.6 mumol/L and 0.6 to 85.0 mumol/L (n = 26) for free and total reduced drug concentrations, respectively. Sources of error in the accurate measurement of peak plasma D-penicillamine levels were identified as oxidative loss and alteration in the free to protein-bound ratio in the period following sample collection.
Webb
B A
BA
Department of Clinical Chemistry, General Hospital, Middlesbrough, UK.
Richardson
S J
SJ
Haslock
I
I
D001172:Arthritis, Rheumatoid / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D006801:Humans; D010084:Oxidation-Reduction; D010396:Penicillamine / Q000097:blood*; D013696:Temperature
D010396:Penicillamine