| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1217480 | Journal of Chromatography B | 2010 | 7 Pages |
BAPTA free acid was identified as the main metabolic product of 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid tetra(actoxymethyl ester) (BAPTA-AM), a neuroprotective agent in cerebral ischemia, in rats. In this paper, liquid chromatography-ultraviolet (LC-UV) and mass spectrometry/mass spectrometry (LC–MS/MS) methods were employed for the determination of BAPTA free acid in rat urine and feces and rat plasma, respectively. By liquid–liquid extraction and LC-UV analysis, a limit of quantitation of 1000 ng/ml using 0.2 ml rat urine for extraction and 250 ng/ml using 1 ml rat fecal homogenate supernatant for extraction could be reached. The assay was linear in the range of 1000–50,000 ng/ml for rat urine and 250–10,000 ng/ml for rat fecal homogenate supernatant. Because the sensitivity of the LC-UV method was apparently insufficient for evaluating the pharmacokinetic profile of BAPTA in rat plasma, a LC–MS/MS method was subsequently developed for the analysis of BAPTA free acid. By protein precipitation and LC–MS/MS analysis, the limit of quantitation was 5 ng/ml using 0.1 ml rat plasma and the linear range was 5.0–500 ng/ml. Both methods were validated and can be used to support a thorough preclinical pharmacokinetic evaluation of BAPTA-AM liposome injection.
