On-line sample clean-up and HPLC analysis of prostaglandins in urine, amniotic fluid, and plasma using a...

An automatable HPLC column switching technique was used for on-line sample clean-up of prostanoids from body fluids. 6-Keto-PGF1 alpha, TxB2, PGF2 alpha and PGE2 in urine, amniotic fluid and plasma were purified by precolumn extraction prior to RP-HPLC-separation. Several precolumn stationary phases were tested, as was the influence of precolumn length and sample acidification. Further, chromatographic behaviour of urine reference compounds was studied. Optimal purification of prostanoids from urine was achieved with microBondapak C18/Corasil as precolumn adsorbent in 1-cm cartridges. Overall recoveries were 64.6 +/- 4.5% for 6-Keto-PGF1 alpha, 72.3 +/- 3.5% for TxB2, 89.6 +/- 3.8% for PGF2 alpha, and 80.4 +/- 3.3% for PGE2. Preliminary results obtained with amniotic fluid and plasma confirmed that precolumn extraction of prostaglandins is also applicable to other body fluids. In discussion, precolumn extraction is compared with the off-line technique using disposable C 18 cartridges.