title: Determination of antibiotics in aquatic environment by solid-phase extraction followed by liquid chromatography-electrospray ionization mass spectrometry.
abstract: A robust and sensitive solid-phase extraction followed by liquid chromatography-electrospray ionization mass spectrometric (LC-ESI-MS) method for determination of antibiotics viz., fluoroquinolones, sulfamethoxazole, trimethoprim and cephalosporines in surface waters was developed. The sample recoveries on Oasis HLB cartridges were found to be >80%. Identification was carried out by LC-ESI-MS/MS. The positive ion ESI mass spectra containing the peaks of quasimolecular ions [M+H](+) allowed the determination of molecular masses whereas the fragment ions obtained by MS/MS of [M+H](+) ions permitted the structural assignment. Quantification was carried out by selective ion monitoring (SIM) using the quasimolecular ions [M+H](+) of the parent compounds. The detection and quantification limits were found to be in the range of 0.6-8.1 and 2.0-24.0 microg/L. The surface waters of different lakes and tanks of Hyderabad, India were found to contain a few antibiotics.
authors.affiliation: Analytical Chemistry Division, Discovery Laboratory, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500007, India. rnrao55@yahoo.com
authors.forename: R
authors.initials: R
authors.lastname: Nageswara Rao
authors.forename: N
authors.initials: N
authors.lastname: Venkateswarlu
authors.forename: R
authors.initials: R
authors.lastname: Narsimha
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis*; D002511:Cephalosporins / Q000032:analysis; D002853:Chromatography, Liquid / Q000379:methods*; D024841:Fluoroquinolones / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D052616:Solid Phase Extraction / Q000379:methods*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D024841:Fluoroquinolones; D014874:Water Pollutants, Chemical; D015662:Trimethoprim, Sulfamethoxazole Drug Combination