Determination of rofecoxib in human plasma and breast milk by high-performance liquid chromatographic assay

A rapid and simple HPLC assay was developed for the determination of rofecoxib in human plasma and breast milk. After solid-phase extraction, rofecoxib was resolved on a C18 column and detected by UV detection at 272 nm. Standard curves were linear over the concentration range 10–2000 μg/L (r2>0.99). Intra- and inter-day coefficients of variation for both matrices were <10% and the limit of quantification was around 10 μg/L.