title: Extraction of ranitidine and nizatidine with using imidazolium ionic liquids prior spectrophotometric and chromatographic detection.
abstract: A new extraction medium was proposed for liquid-liquid extraction of the histamine H2 receptor antagonists ranitidine (RNT) and nizatidine (NZT). The ionic liquids with low vapor pressure and favorable solvating properties for a range of compounds such as 1-butyl-3-methylimidazolium hexafluorophosphate [C4mim][PF6] and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [C4mim][Tf2N] were tested for isolation of analytes. The extraction parameters of RNT and NZT, namely, amount of ionic liquid, pH of sample solution, shaking and centrifugation time were optimized. The isolation processes were performed with 1 mL of the ionic liquids. The extracted samples (pH values near 4) were shaken at 1750 rpm. The influence of interfering substances on the efficiency of extraction process was also studied. Methods for the histamine H2 receptor antagonists (ranitidine and nizatidine) determination after their separation using imidazolium ionic liquids by high performance liquid chromatography (HPLC) combined with UV spectrophotometry were developed. The application of ionic liquids in extraction step allows for selective isolation of analytes from aqueous matrices and their preconcentration. The above methods were applied to the determination of RNT and NZT in environmental samples (river water and wastewater after treatment).
authors.affiliation: University of Bialystok, Institute of Chemistry, Hurtowa 1, 15-399 Bialystok, Poland. Electronic address: i.kiszkiel@interia.eu.
authors.forename: Ilona
authors.initials: I
authors.lastname: Kiszkiel
authors.affiliation: University of Bialystok, Institute of Chemistry, Hurtowa 1, 15-399 Bialystok, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Starczewska
authors.affiliation: University of Bialystok, Institute of Chemistry, Hurtowa 1, 15-399 Bialystok, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Leśniewska
authors.affiliation: University of Bialystok, Institute of Chemistry, Hurtowa 1, 15-399 Bialystok, Poland.
authors.forename: Patrycja
authors.initials: P
authors.lastname: Późniak
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005618:Fresh Water / Q000032:analysis; D006635:Histamine H2 Antagonists / Q000032:analysis; D007093:Imidazoles / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry; D059625:Liquid-Liquid Extraction / Q000379:methods; D016567:Nizatidine / Q000032:analysis*; D011899:Ranitidine / Q000032:analysis*; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D062065:Wastewater / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D006635:Histamine H2 Antagonists; D007093:Imidazoles; D052578:Ionic Liquids; D016567:Nizatidine; D011899:Ranitidine; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Extraction techniques; Ionic liquids; Nizatidine; Ranitidine; Surface water analysis