title: Magnetic solid-phase extraction based on methylcellulose coated-Fe3O4-SiO2-phenyl for HPLC-DAD analysis of sildenafil and its metabolite in biological samples.
abstract: In the present study, magnetic nanoparticles (MNPs) with phenyl functionalized core and a hydrophilic methylcellulose coating were synthesized. The functionalized MNPs showed excellent dispersibility in aqueous solution and they were applied to magnetic solid phase extraction (MSPE) of sildenafil and its metabolite, desmethyl sildenafil, from human urine and plasma samples followed by high performance liquid chromatographic analysis. The factors that may influence the extraction, including the amount of MNPs, pH and salt concentration of sample solution, extraction and desorption time, and the volume of desorption solvent, were investigated in detail. Under the optimum MSPE conditions, the developed method showed satisfactory reproducibility with intra-day and inter-day relative standard deviations less than 8.2% and low limits of detection of 0.41-0.96 ng mL(-1) from urine and plasma samples. The proposed material possessed good water compatibility and demonstrated excellent applicability for biological samples.
authors.affiliation: Tongji School of Pharmacy, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Minqiong
authors.initials: M
authors.lastname: Tang
authors.affiliation: Tongji School of Pharmacy, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Tongji School of Pharmacy, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Jiang
authors.affiliation: Tongji School of Pharmacy, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Li
authors.initials: L
authors.lastname: Xu
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine, Wuhan University, Wuhan, China. Electronic address: shizg@whu.edu.cn.
authors.forename: Zhi-Guo
authors.initials: ZG
authors.lastname: Shi
authors.affiliation: Institute of Oceanographic Instrumentation, Shandong Academy of Sciences, Qingdao 266001, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Institute of Oceanographic Instrumentation, Shandong Academy of Sciences, Qingdao 266001, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
mesh_terms: D002851:Chromatography, High Pressure Liquid; D005290:Ferric Compounds / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008747:Methylcellulose / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*; D010879:Piperazines / Q000097:blood* / Q000302:isolation & purification / Q000652:urine*; D011687:Purines / Q000097:blood / Q000302:isolation & purification / Q000652:urine; D015203:Reproducibility of Results; D000068677:Sildenafil Citrate; D012822:Silicon Dioxide / Q000737:chemistry*; D052616:Solid Phase Extraction; D013449:Sulfonamides / Q000097:blood* / Q000302:isolation & purification / Q000652:urine*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; D010636:Phenols; D010879:Piperazines; D011687:Purines; D013449:Sulfonamides; D014874:Water Pollutants, Chemical; C000499:ferric oxide; D012822:Silicon Dioxide; D008747:Methylcellulose; D000068677:Sildenafil Citrate
keywords: Magnetic nanoparticle; Magnetic solid phase extraction; Methylcellulose; Sildenafil