title: Preconcentration of indapamide from human urine using molecularly imprinted solid-phase extraction.
abstract: A simple, sensitive, and selective molecularly imprinted solid-phase extraction and spectrophotometric method has been developed for the clean-up and preconcentration of indapamide from human urine. Molecularly imprinted polymers were prepared by a non-covalent imprinting approach using indapamide as a template molecule, 2-(trifluoromethyl) acrylic acid as a functional monomer, ethylene glycol dimethacrylate as a crosslinker, N,N-azobisisobutyronitrile as a thermal initiator and acetonitrile as a porogenic solvent. A non-imprinted polymer was also prepared in the same way, but in the absence of template. Molecularly imprinted polymer and non-imprinted polymer sorbents were dry-packed into solid-phase extraction cartridges. Eluates from cartridges were analyzed using a spectrophotometer for the determination of indapamide by referring to the calibration curve in the range 0.14-1.50 μg/mL. Preconcentration factor, limit of detection, and limit of quantification were 16.30, 0.025 μg/mL, and 0.075 μg/mL, respectively. A relatively high imprinting factor (9.3) was also achieved and recovery values for the indapamide spiked into human urine were in the range of 80.1-81.2%. In addition, relatively low within-day (0.17-0.42%) and between-day (1.1-1.4%) precision values were obtained as well. The proposed molecularly imprinted solid-phase extraction and spectrophotometric method was successfully applied to selective extraction, preconcentration, and determination of indapamide from human urine samples.
authors.affiliation: Faculty of Pharmacy, Department of Analytical Chemistry, Gazi University, Ankara, Turkey.
authors.forename: Hüma
authors.initials: H
authors.lastname: Yılmaz
authors.affiliation: Faculty of Pharmacy, Department of Analytical Chemistry, Gazi University, Ankara, Turkey.
authors.forename: Hasan
authors.initials: H
authors.lastname: Basan
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000179:Acrylates / Q000737:chemistry; D002138:Calibration; D006801:Humans; D007190:Indapamide / Q000032:analysis / Q000652:urine*; D057230:Limit of Detection; D008689:Methacrylates / Q000737:chemistry; D054802:Molecular Imprinting; D009570:Nitriles / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D015203:Reproducibility of Results; D052616:Solid Phase Extraction; D012997:Solvents; D013053:Spectrophotometry; D016482:Urinalysis / Q000379:methods*; D014556:Urine / Q000737:chemistry
chemical_list: C411824:2-(trifluoromethyl)acrylic acid; D000097:Acetonitriles; D000179:Acrylates; D008689:Methacrylates; D009570:Nitriles; D011108:Polymers; D012997:Solvents; C004919:ethylene dimethacrylate; D007190:Indapamide; C004526:azobis(isobutyronitrile); C032159:acetonitrile
keywords: Human urine; Indapamide; Molecularly imprinted polymers; Preconcentration solid-phase extraction