title: Baseline-Corrected Second-Order Derivative Electroanalysis Combined With Ultrasound-Assisted Liquid-Liquid Microextraction: Simultaneous Quantification of Fluoroquinolones at Low Levels.
abstract: A baseline-corrected second-order derivative procedure and a miniaturized sample preparation based on low-density solvent and ultrasound-assisted liquid-liquid microextraction (LDS-UA-LLME) was combined to provide the simultaneous electroanalysis of three fluoroquinolones (FQ) as emerging contaminants (ECs). The enhanced mathematical processing provided the best separation with an accurate measurement of the overlapping peaks during the simultaneous electro-oxidation of target FQs that were directly dropped on the surface of carbon nanofiber-modified screen-printed electrodes. The adapted LDS-UA-LLME protocol was the key step involved in the sample preparation, which preconcentrate target analytes from diluted tap water samples with an enrichment factor of around 80×, allowing their quantification at trace levels. This combined feature demonstrated the unique application of an electroanalytical technique for the simultaneous electroanalysis of three FQs in spiked tap water samples, with recovery values remarkably close to 100%.
authors.affiliation: Faculdade de Ciências Exatas e Tecnologia, Universidade Federal da Grande Dourados , Rodovia Dourados-Itahum, km 12, Dourados-MS, 79804-970, Brazil.
authors.forename: Luiz Henrique
authors.initials: LH
authors.lastname: de Oliveira
authors.affiliation: Faculdade de Ciências Exatas e Tecnologia, Universidade Federal da Grande Dourados , Rodovia Dourados-Itahum, km 12, Dourados-MS, 79804-970, Brazil.
authors.forename: Magno Aparecido Gonçalves
authors.initials: MA
authors.lastname: Trindade
mesh_terms: D002244:Carbon / Q000737:chemistry; D060766:Drinking Water / Q000032:analysis; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D004867:Equipment Design; D024841:Fluoroquinolones / Q000032:analysis* / Q000302:isolation & purification; D057230:Limit of Detection; D059627:Liquid Phase Microextraction / Q000295:instrumentation / Q000379:methods*; D057139:Nanofibers / Q000737:chemistry; D010084:Oxidation-Reduction; D013010:Sonication / Q000295:instrumentation / Q000379:methods*; D014867:Water / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000302:isolation & purification
chemical_list: D060766:Drinking Water; D024841:Fluoroquinolones; D014874:Water Pollutants, Chemical; D014867:Water; D002244:Carbon