Evaluation of ursodeoxycholic acid bioavailability from immediate- and sustained-release preparations using gas chromatography-mass spectrometry and high-performance liquid chromatography

Arzneimittelforschung. 2000 Feb;50(2):129-34.


An improved procedure is presented for the determination of ursodeoxycholic acid (CAS 128-13-2, UDCA) in human plasma and bile after oral administration of UDCA-containing dosage forms. The plasma samples after solid-phase extraction with silica-based C18- and strong anion exchange cartridges were assayed by gas chromatography-mass spectrometry (GC-MS) using selected-ion monitoring. The hexafluoroisopropyl trifluoroacetate ester derivative of UDCA was selected for GC analysis since it is easily and rapidly prepared by a one-step reaction. Biliary UDCA levels were determined by a rapid and simple high-performance liquid chromatographic (HPLC) method with on-line sample purification. This analytical protocol was used to investigate the pharmacokinetic of a new sustained-release capsule of UDCA in comparison with a reference immediate-release preparation after single oral administration. Statistical evaluation of the area under the plasma concentration-time curves indicated that two formulations are equivalent with regard to the amount of drug absorbed. However, pharmacokinetic data showed that with the sustained-release preparation a significantly delayed mean peak plasma level was reached compared with the reference preparation. Moreover, the immediate- and extended-release capsules were found to achieve a comparable degree of biliary enrichment with UDCA.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Area Under Curve
  • Bile / chemistry
  • Bile Acids and Salts / chemistry
  • Biological Availability
  • Capsules
  • Chromatography, High Pressure Liquid
  • Cross-Over Studies
  • Delayed-Action Preparations
  • Female
  • Gas Chromatography-Mass Spectrometry
  • Humans
  • Male
  • Microspheres
  • Single-Blind Method
  • Ursodeoxycholic Acid / administration & dosage
  • Ursodeoxycholic Acid / pharmacokinetics*


  • Bile Acids and Salts
  • Capsules
  • Delayed-Action Preparations
  • Ursodeoxycholic Acid