Determination of the anxiolytic agent 8-chloro-6-(2-chlorophenyl)-4H-imidazo-[1,5-alpha] [1,4]-benzodiazepine-3-carboxamide in whole blood, plasma or urine by high-performance liquid chromatography.
A rapid, sensitive and specific high-performance liquid chromatographic (HPLC) assay was developed for the determination of 8-chloro-6-(2-chlorophenyl)-4H-imidazo-[1,5-alpha]-[1,4]-benzodiazepine-3-carboxamide [I] and its 4-hydroxy metabolite, 8-chloro-6-(2-chlorophenyl)-4-hydroxy-4H-imidazo-[1,5-alpha] [1,4]-benzodiazepine-3-carboxamide [II] in whole blood, plasma or urine. The assay for both compounds involves extraction into diethyl ether-methylene chloride (70:30) from blood, plasma, or urine buffered to pH 9.0. The overall recoveries of [I] and [II] are 92.0 +/- 5.4% (S.D.) and 90.3 +/- 4.9% (S.D.), respectively. The sensitivity limit of detection is 50 ng/ml of blood, plasma, or urine using a UV detector at 254 nm. The HPLC assay was used to monitor the blood concentration-time fall-off profiles, and urinary excretion profiles in the dog following single 1 mg/kg intravenous and 5 mg/kg oral doses, and following multiple oral doses of 100 mg/kg/day of compound [I].
Chapter III Whole Blood Sample Clean-Up for Chromatographic Analysis
Publisher Summary This chapter discusses the general strategies for blood sample handling for various drugs and presents an example of measurement of cyclosporine. It also describes the metabolites of cyclosporine. Cyclosporine proved to be a good example because blood level measurement is of high clinical impact and the whole spectrum of sample preparation strategies has been applied for cyclosporine determination. Developing an adequate sample preparation method several factors must be considered: (1) the chemical properties of the constituents in question, and (2) the biological matrix. The substance of interest must be extracted from its biological matrix prior to chromatographic analysis. Proteins and other macromolecules may interfere with detection and columns may get plugged or rapidly inactivated. A good extraction procedure should be reproducible with little loss of the material of analytical interest. It should be rapid and allow several samples to be analyzed in a short period of time and it should be inexpensive. Because of better handling the use of plasma or serum as biological matrix is preferable over blood. Plasma and serum is produced by removing the cellular components of blood by centrifugation or natural clotting.
United Nations Convention on the Law of the Sea 1982, A Commentary
Volume VI is the sixth substantive volume to be published in the series. It deals with the work of the First Committee at the Third UN Conference on the Law of the Sea, namely the international seabed area. The volume thus embraces the deep seabed mining regime set out in Part XI of the 1982 Convention on the Law of the Sea together with the 1994 Agreement on its implementation. Completion of this commentary was delayed first by the consultations and negotiations that commenced in 1990 and led to the 1994 Agreement and the entry into force of the Convention. It was further delayed until the Assembly of the International Seabed Authority approved the detailed mining regulations in 2000. Additional supplementary material can be found at UNCLOS 1982 Commentary: Supplementary Documents.