title: Dual lifetime referenced fluorometry for the determination of doxorubicin in urine.
abstract: Dual lifetime referencing (DLR) is introduced as a rapid and self-referenced method for measuring the concentration of a fluorescent analyte in solution. The fluorescent cancer chemotherapeutic doxorubicin was chosen as a medically relevant analyte and blended with a reference dye (Ru(dpp)(3)) that displays overlapping excitation and emission spectra. The relative contributions of the short-lived (nanoseconds) fluorescent analyte and the long-lived (microseconds) reference dye define the observed lifetime. Measuring this lifetime by both frequency-domain DLR and time-domain DLR yields similar analytical ranges and limits of detection (0.4 μM). To assess the matrix effect of medical samples, the standard addition method was employed to both modes of DLR. Urine was spiked with doxorubicin and recovery rates of ≥97% were obtained.
authors.affiliation: Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, D-93040 Regensburg, Germany.
authors.forename: Fernando
authors.initials: F
authors.lastname: Martínez Ferreras
authors.forename: Otto S
authors.initials: OS
authors.lastname: Wolfbeis
authors.forename: Hans H
authors.initials: HH
authors.lastname: Gorris
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000652:urine*; D004317:Doxorubicin / Q000652:urine*; D005456:Fluorescent Dyes / Q000737:chemistry; D005470:Fluorometry / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D009942:Organometallic Compounds / Q000737:chemistry*; D010618:Phenanthrolines / Q000737:chemistry*
chemical_list: D000903:Antibiotics, Antineoplastic; D005456:Fluorescent Dyes; D009942:Organometallic Compounds; D010618:Phenanthrolines; D004317:Doxorubicin; C041132:tris(4,7-diphenyl-1,10-phenanthroline)ruthenium (II)