title: Analysis of gamma-(cholesteryloxy)butyric acid in biologic samples by derivatization with 5-(bromomethyl)fluorescein followed by high-performance liquid chromatography with laser-induced fluorescence detection.
abstract: This report describes the first application of 5-(bromo-methyl)fluorescein (5-BMF) for the quantitation of a pharmaceutically relevant carboxyl-containing analyte in a biological matrix. An analytical method for quantitation of gamma-(cholesteryloxy)butyric acid (CBA), a relatively new antitumor agent, in different tissues of Sprague-Dawley rats was developed. 5-BMF was employed to form a stable and spectrally well-characterized conjugate of CBA. The derivatization yield was maximized by optimizing several reaction variables. The conjugate was separated by high-performance liquid chromatography and quantitated by a laboratory-constructed argon ion laser fluorometer. The detection limits for CBA were 4.6 x 10(-9) and 6.34 x 10(-11) M by conventional and laser-induced fluorescence (LIF), respectively. A derivatization limit of detection of 1.85 x 10(-9) M was achieved by LIF for the conjugate The analytical method was useful for quantitation of CBA in various tissues in the picogram per milliliter range.
authors.affiliation: Department of Pharmacy and Pharmaceutics, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-0533, USA.
authors.forename: P S
authors.initials: PS
authors.lastname: Mukherjee
authors.forename: H T
authors.initials: HT
authors.lastname: Karnes
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000032:analysis*; D002784:Cholesterol / Q000031:analogs & derivatives* / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D005452:Fluoresceins; D007202:Indicators and Reagents; D007834:Lasers; D051381:Rats; D017207:Rats, Sprague-Dawley; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000970:Antineoplastic Agents; D005452:Fluoresceins; D007202:Indicators and Reagents; C081567:5-(bromomethyl)fluorescein; C103872:4-(cholesteryloxy)butyric acid; D002784:Cholesterol