Fa. Mohamed et al., AN IMPROVED HPLC PROCEDURE FOR THE QUANTITATION OF DICLOFENAC IN PLASMA, Journal of liquid chromatography, 17(5), 1994, pp. 1065-1088
A rapid, simple and sensitive high performance liquid chromatographic
(HPLC) assay for the quantitation of diclofenac (DF) in dog plasma has
been developed. Mefenamic acid (MA) was used as the internal standard
. After acidification, DF and MA were extracted from plasma into chlor
oform. Separation was achieved using a C18 reversed phase column. The
retention times of DF and MA were 3.8 and 6.3 min., respectively at th
e flow rate of 1.5 ml/min. The DF interday standard plots (n=4) were h
ighly linear (r>0.99) over the concentration range of 0.01 to 10 mu g/
ml. DF mean recovery was 98% +/- 5.5, and the % CV of intra- and inter
-day sample analyses ranged from 2.6 to 10.8% for the entire calibrati
on range. The limit of quantification of DF in plasma was 0.01 mu g/ml
with the CV of 9.4%. The method was applied for the determination of
the pharmacokinetic parameters of DF given by oral and iv bolus admini
stration to dogs.