| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1198889 | Journal of Chromatography A | 2016 | 10 Pages |
•A new stir bar sorptive extraction method was proposed for losartan and valsartan.•Ni:ZnS NPs loaded on activated carbon was used as the coating material for stir bar.•Important parameters effecting the extraction were optimized by chemomotery method.•The preconcentrated analytes were determined by HPLC.•The method was applied to the determination of analytes in urine and plasma samples.
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 0.4–50 μg L−1 and 0.5–50 μg L−1 and good RSDs (at level of 5 μg L−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 0.15 μg L−1 for LOS and VAL, respectively. The developed method was successfully applied to the determination of LOS and VAL in urine and plasma matrices.
