title: Application of modified stir bar with nickel:zinc sulphide nanoparticles loaded on activated carbon as a sorbent for preconcentration of losartan and valsartan and their determination by high performance liquid chromatography.
abstract: In this study, the stir bar was coated for the first time with the ​nicel:zins sulphide nanoparticles (Ni:ZnS NPs) loaded on activated carbon (AC) (Ni:ZnS-AC) as well as 1-ethyl-3-methylimidazolium hexafluorophosphate ionic liquid (IL) using sol gel technique and was used for stir bar sorptive extraction (SBSE) of losartan (LOS) and valsartan (VAL) as the model compounds. The extracted analytes were then quantified by high performance liquid chromatography (HPLC) equipped with an ultra violet detector. The best extraction performance for LOS and VAL was obtained through the optimization of the parameters affecting SBSE including pH of sample solution, ionic strength, extraction time, volume of desorption solvent, desorption time, and stirring speed. The fractional factorial design (FFD) was used to find the most important parameters, which were then optimized by the central composite design (CCD) and the desirability function (DF). Under the optimal experimental conditions, wide linear ranges of 0.4-50μgL(-1) and 0.5-50μgL(-1) and good RSDs (at level of 5μgL(-1) and n=6) of 4.4 and 4.9% were obtained for LOS and VAL, respectively. With the enrichment factors (EFs) of 188.6 and 184.8-fold, the limits of detection (LODs, S/N=3) of the developed method were found to be 0.12 and 0.15μgL(-1) for LOS and VAL, respectively. The developed method was successfully applied to the determination of LOS and VAL in urine and plasma matrices.
authors.affiliation: Department of Chemistry, Faculty of Science, Yazd University, Yazd 89195-741, Iran.
authors.forename: Arezou Amiri
authors.initials: AA
authors.lastname: Pebdani
authors.affiliation: Department of Chemistry, Faculty of Science, Yazd University, Yazd 89195-741, Iran. Electronic address: sdadfarnia@yazd.ac.ir.
authors.forename: Shayesteh
authors.initials: S
authors.lastname: Dadfarnia
authors.affiliation: Department of Chemistry, Faculty of Science, Yazd University, Yazd 89195-741, Iran.
authors.forename: Ali Mohammad Haji
authors.initials: AMH
authors.lastname: Shabani
authors.affiliation: Department of Chemistry, Behbahan Khatam Alanbia University of Technology, Behbahan, Iran.
authors.forename: Saeid
authors.initials: S
authors.lastname: Khodadoust
authors.affiliation: Food and Drug Laboratory Research Center, Food and Drug Organization, Ministry of Health and Medical Education, Tehran, Iran.
authors.forename: Soheila
authors.initials: S
authors.lastname: Haghgoo
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D057230:Limit of Detection; D019808:Losartan / Q000032:analysis / Q000302:isolation & purification*; D053758:Nanoparticles / Q000737:chemistry; D009532:Nickel / Q000737:chemistry*; D009994:Osmolar Concentration; D013440:Sulfides / Q000737:chemistry*; D000068756:Valsartan / Q000032:analysis / Q000302:isolation & purification*; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D013440:Sulfides; D017967:Zinc Compounds; D002244:Carbon; D009532:Nickel; D000068756:Valsartan; D019808:Losartan; C031238:zinc sulfide
keywords: Experimental design; HPLC; Losartan; Plasma; Stir bar sorptive extraction; Urine; Valsartan