title: Measurement of levofloxacin in human plasma samples for a reliable and accessible drug monitoring.
abstract: OBJECTIVE
  Levofloxacin monitoring is recommended to obtain clinical cure and low incidence of antimicrobial resistance. During the monitoring procedure, levofloxacin should be measured in plasma samples and several assays are reported for this purpose. However, those methods do not have all of the characteristics for an accessible and reliable drug monitoring. For this reason, we develop a method that has all of the essential characteristics for levofloxacin monitoring.
  
  
  METHODS
  The procedure of validation was done in terms of Food and Drug Administration guidelines. Subsequently, our assay was applied in plasma samples obtained from healthy volunteers with a single oral administration of levofloxacin as well as patients with respiratory diseases under levofloxacin therapy.
  
  
  RESULTS
  Levofloxacin was extracted from samples using only two precipitation steps. Our assay had a rapid run time (5min), adequate sensitivity (0.05μg/ml of lower limit of quantification), and acceptable parameters of validation. Moreover, compound identities were supported using three dimensional spectra and purities were confirmed employing similarity factors (values>900). Variable concentrations of levofloxacin in samples were observed during the application.
  
  
  CONCLUSIONS
  Levofloxacin is successfully quantified using our method that shows reliable results, appropriate range, rapid analyses, and cost-effective measurements under a simple and easy technique while all prior methods did not have it all together. Consequently, our method is a valuable tool for routine drug monitoring. Moreover, a complete evaluation of specificity was done for levofloxacin in plasma samples for the first time. Meanwhile, the application data supported the necessity of levofloxacin monitoring.
authors.affiliation: Department of Pharmacology, School of Medicine, University of San Luis Potosi, San Luis Potosi, S.L.P., Mexico.
authors.forename: Othoniel Hugo
authors.initials: OH
authors.lastname: Aragon-Martinez
authors.affiliation: Department of Research, School of Dentistry, Cuauhtémoc University, San Luis Potosi, S.L.P., Mexico.
authors.forename: Mario Alberto
authors.initials: MA
authors.lastname: Isiordia-Espinoza
authors.affiliation: Department of Pharmacology, School of Medicine, University of San Luis Potosi, San Luis Potosi, S.L.P., Mexico.
authors.forename: Othir
authors.initials: O
authors.lastname: Galicia
authors.affiliation: Diagnostic Clinic Dentistry School, University of San Luis Potosí, San Luis Potosí, S.L.P., Mexico.
authors.forename: Saray
authors.initials: S
authors.lastname: Aranda Romo
authors.affiliation: Center of Respiratory Diseases, San Luis Potosí, S.L.P., Mexico.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Gómez Gómez
authors.affiliation: Department of Pharmacy and Drug Technology, School of Chemistry Sciences, University of San Luis Potosi, San Luis Potosi, S.L.P., Mexico.
authors.forename: Silvia
authors.initials: S
authors.lastname: Romano-Moreno
authors.affiliation: Department of Pharmacology, School of Medicine, University of San Luis Potosi, San Luis Potosi, S.L.P., Mexico. Electronic address: martinej@uaslp.mx.
authors.forename: Flavio
authors.initials: F
authors.lastname: Martinez-Morales
mesh_terms: D000900:Anti-Bacterial Agents / Q000097:blood*; D016903:Drug Monitoring / Q000592:standards*; D006801:Humans; D064704:Levofloxacin / Q000097:blood*; D015203:Reproducibility of Results
chemical_list: D000900:Anti-Bacterial Agents; D064704:Levofloxacin
keywords: Diode array technology; Drug monitoring; Levofloxacin; Liquid chromatography; Validation