High-performance liquid chromatographic assay for the determination of 5-aminosalicylic acid and acetyl-5-aminosalicylic acid concentrations in endoscopic intestinal biopsy in humans

J Chromatogr. 1991 Mar 8;564(1):296-302. doi: 10.1016/0378-4347(91)80094-s.


A high-performance liquid chromatographic method for the simultaneous determination of 5-amino-salicylic acid (5-ASA) and N-acetyl-5-ASA (Ac-5-ASA) concentrations in endoscopic mucosal biopsy homogenates is presented. The mean recoveries of 5-ASA and Ac-5-ASA from spiked blank biopsy homogenates ranged from 95.9 to 120% and from 92.5 to 100%, respectively. The coefficients of variation for 5-ASA and Ac-5-ASA were 0.7-8.6% and 1.4-12.9%, respectively. This method is useful for direct determination of topical availability of 5-ASA and Ac-5-ASA and probably an accurate parameter of drug bioavailability.

MeSH terms

  • Aminosalicylic Acids / analysis*
  • Biopsy
  • Chromatography, High Pressure Liquid / methods*
  • Chromatography, High Pressure Liquid / statistics & numerical data
  • Endoscopy, Gastrointestinal
  • Humans
  • Intestinal Mucosa / chemistry*
  • Mesalamine


  • Aminosalicylic Acids
  • Mesalamine
  • N-acetyl-5-aminosalicylic acid