title: Simultaneous spectrophotometric determination of 2-thiouracil and 2-mercaptobenzimidazole in animal tissue using multivariate calibration methods: concerns and rapid methods for detection.
abstract: Two multivariate calibration methods, partial least squares (PLS) and principal component regression (PCR), were applied to the spectrophotometric simultaneous determination of 2-mercaptobenzimidazole (MB) and 2-thiouracil (TU). A genetic algorithm (GA) using partial least squares was successfully utilized as a variable selection method. The concentration model was based on the absorption spectra in the range of 200 to 350 nm for 25 different mixtures of MB and TU. The calibration curve was linear across the concentration range of 1 to 10 microg mL(-1) and 1.5 to 15 microg mL(-1) for MB and TU, respectively. The values of the root mean squares error of prediction (RMSEP) were 0.3984, 0.1066, and 0.0713 for MB and 0.2010, 0.1667, and 0.1115 for TU, which were obtained using PCR, PLS, and GA-PLS, respectively. Finally, the practical applicability of the GA-PLS method was effectively evaluated by the concurrent detection of both analytes in animal tissues. It should also be mentioned that the proposed method is a simple and rapid way that requires no preliminary separation steps and can be used easily for the analysis of these compounds, especially in quality control laboratories.
authors.affiliation: Center of Excellence in Electrochemistry, Faculty of Chemistry, Univ. of Tehran, P.O. Box 14155-6455, Tehran, Iran.
authors.forename: Abolghasem
authors.initials: A
authors.lastname: Beheshti
authors.forename: Siavash
authors.initials: S
authors.lastname: Riahi
authors.forename: Eslam
authors.initials: E
authors.lastname: Pourbasheer
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Ganjali
authors.forename: Parviz
authors.initials: P
authors.lastname: Norouzi
mesh_terms: D000818:Animals; D001562:Benzimidazoles / Q000032:analysis* / Q000737:chemistry; D002138:Calibration; D002417:Cattle; D002623:Chemistry Techniques, Analytical / Q000379:methods* / Q000706:statistics & numerical data; D016018:Least-Squares Analysis; D015999:Multivariate Analysis; D025341:Principal Component Analysis / Q000379:methods; D012756:Sheep; D013053:Spectrophotometry / Q000379:methods* / Q000706:statistics & numerical data; D013889:Thiouracil / Q000032:analysis* / Q000737:chemistry
chemical_list: D001562:Benzimidazoles; D013889:Thiouracil; C030698:2-mercaptobenzimidazole