title: Development of a Terbium-Sensitized Fluorescence Method for Analysis of Silibinin.
abstract: Silibinin is a natural flavonoid with potent anticancer properties, as shown in both in vitro and in vivo experiments. Various methods have been used for silibinin analysis. Terbium-sensitized fluorescence methods have been widely used for the determination of drugs in pharmaceutical preparations and biological samples in recent years. The present work is aimed at providing a simple analytical method for the quantitative determination of silibinin in aqueous solutions based on the formation of a fluorescent complex with terbium ion. Terbium concentration, pH, and volume of buffer, the important effective parameters for the determination of silibinin by the proposed method, were optimized using response surface methodology. The fluorescence intensity of silibinin was measured at 545 nm using λex = 334 nm. The developed method was applied for the determination of silibinin in plasma samples after protein precipitation with acetone. Under optimum conditions, the method provided a linear range between 0.10 and 0.50 mg/L, with a coefficient of determination (R2) of 0.997. The LOD and LOQ were 0.034 and 0.112 mg/L, respectively. These results indicate that the developed method is a simple, low-cost, and suitable analytical method for the quantification of silibinin in aqueous solution and plasma samples.
authors.affiliation: Tabriz University of Medical Sciences, Liver and Gastrointestinal Diseases Research Center, Tabriz 51664, Iran.
authors.forename: Saba
authors.initials: S
authors.lastname: Ershadi
authors.affiliation: Tabriz University of Medical Sciences, Pharmaceutical Analysis Research Center, Tabriz 51664, Iran.
authors.forename: Abolghasem
authors.initials: A
authors.lastname: Jouyban
authors.affiliation: Tabriz University of Medical Sciences, Faculty of Pharmacy, Department of Pharmaceutical Biotechnology, Tabriz 51664, Iran.
authors.forename: Ommoleila
authors.initials: O
authors.lastname: Molavi
authors.affiliation: Tabriz University of Medical Sciences, Drug Applied Research Center, Tabriz 51664, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Shayanfar
mesh_terms: D002021:Buffers; D006863:Hydrogen-Ion Concentration; D000077385:Silybin; D012838:Silymarin / Q000032:analysis*; D013050:Spectrometry, Fluorescence; D013725:Terbium / Q000737:chemistry*
chemical_list: D002021:Buffers; D012838:Silymarin; D013725:Terbium; D000077385:Silybin