title: Fast and environmentally friendly quantitative analysis of active agents in anti-diabetic tablets by an alternative laser-induced breakdown spectroscopy (LIBS) method and comparison to a validated reversed-phase high-performance liquid chromatography (RP-HPLC) method.
abstract: Laser-induced breakdown spectroscopy (LIBS) is evaluated as a potential analytic technique for rapid screening and quality control of anti-diabetic tablets. This paper proposes a simple LIBS-based method for the quantitative analysis of two active pharmaceutical ingredients (APIs): metformin (Met) and glybenclamide (Gly). In order to quantify both APIs, chlorine (Cl) concentration was estimated by employing the Cl/Br optical emission ratio, where Br was introduced as internal standard. Calibration curves were prepared, achieving linearity higher than 99%. On the other hand, for comparison to the proposed method, an isocratic reversed-phase high-performance liquid chromatography (RP-HPLC) method was also developed for quantitative determination of the same analytes by ultraviolet (UV) detection. The chromatographic separation was achieved on a Phenomenex Hypersil C18, 250 mm × 4.6 mm, 5 μm column. The mobile phase was K(2)HPO(4)/H(3)PO(4)-CH(3)OH and flow rate was 1.0 mL min(-1). The method is linear over a range of 10-60 μg mL(-1) for Gly and 5-30 μg mL(-1) for Met and the correlation coefficients were ≥0.99. Recoveries were found to be in the range of 95-101%. Furthermore, four different commercial brands of each active agent were evaluated by both proposed LIBS and chromatographic methods and results were compared with each other. The comparison was satisfactorily validated by analysis of variance (ANOVA).
authors.affiliation: Centro de Investigaciones en Óptica, León, Gto., México. ulises@cio.mx
authors.forename: Victor Ulises
authors.initials: VU
authors.lastname: Contreras
authors.forename: Marco A
authors.initials: MA
authors.lastname: Meneses-Nava
authors.forename: Nancy
authors.initials: N
authors.lastname: Ornelas-Soto
authors.forename: Oracio
authors.initials: O
authors.lastname: Barbosa-García
authors.forename: Pedro L
authors.initials: PL
authors.lastname: López-de-Alba
authors.forename: José L
authors.initials: JL
authors.lastname: Maldonado
authors.forename: Gabriel
authors.initials: G
authors.lastname: Ramos-Ortiz
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Acevedo-Aguilar
authors.forename: Leticia
authors.initials: L
authors.lastname: López-Martínez
mesh_terms: D000704:Analysis of Variance; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D056148:Chromatography, Reverse-Phase / Q000379:methods*; D005905:Glyburide / Q000032:analysis / Q000737:chemistry / Q000592:standards; D007004:Hypoglycemic Agents / Q000032:analysis* / Q000737:chemistry / Q000592:standards; D016014:Linear Models; D008687:Metformin / Q000032:analysis / Q000737:chemistry / Q000592:standards; D015203:Reproducibility of Results; D013057:Spectrum Analysis / Q000379:methods*; D013607:Tablets / Q000032:analysis / Q000737:chemistry / Q000592:standards
chemical_list: D007004:Hypoglycemic Agents; D013607:Tablets; D008687:Metformin; D005905:Glyburide