TISSUE EXTRACTION AND HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF KETOPROFEN ENANTIOMERS

Local transcutaneous delivery of non-steroidal anti-inflammatory drugs avoids gastrointestinal side effects and concentrates drugs in the in tended tissues. An extraction and HPLC method was developed for ketopr ofen in skin, fascia and muscle. Tissue samples were homogenized in Na HCO3. After methylene chloride removal of lipids, the aqueous layer wa s acidified with HCl and back extracted into isooctane/isopropanol. Ke toprofen was derivatized with ethylchloroformate/S(-)-alpha-phenylethy lamine in triethylamine, then detected by HPLC, Ketoprofen recovery wa s linear (1-33 mu g/g) and was detected in these tissues following in vivo cathodic iontophoresis (160 mAmin). This represents the first no n-radioactive method for determination of ketoprofen in tissues follow ing transcutaneous iontophoresis. (C) 1998 Elsevier Science B.V.