1.High-throughput method for the determination of nitroimidazoles in muscle samples by liquid chromatography coupled to mass spectrometry.
Rúbies A1, Sans G, Kumar P, Granados M, Companyó R, Centrich F. Anal Bioanal Chem. 2015 Jun;407(15):4411-21. doi: 10.1007/s00216-014-8436-x. Epub 2015 Jan 11.
We present a high-throughput confirmatory method for the analysis of 11 nitroimidazoles in muscle samples (metronidazole, MNZ; dimetridazole, DMZ; ronidazole, RNZ; tinidazole, TNZ; carnidazole, CRZ; secnidazole semihydrate, SCZ; ornidazole, ORZ; metronidazole-hydroxy, MNZ-OH; ipronidazole, IPZ; ipronidazole-hydroxy, IPZ-OH; and dimetridazole-hydroxy, HMMNI). Extraction with acetonitrile is efficient and simple, with the majority of recoveries ranging between 65 and 101%, and without the need for clean-up of the extracts. The chromatographic analysis is performed using UPLC-QqQ-MS in the MRM mode, with an electrospray source operated in positive mode. Total chromatographic analysis time is 12 min. This method has been fully validated in muscle according to Decision 657/2002/CE guidelines, and the CCα values obtained were in the range of 0.04-0.4 μg·kg(-1). The method is currently used for the analysis of muscle samples and has been tested in other matrices of animal origin, such as kidney, retina and egg, with excellent results.
2.Rapid confirmatory method for the determination of 11 nitroimidazoles in egg using liquid chromatography tandem mass spectrometry.
Cronly M1, Behan P, Foley B, Malone E, Regan L. J Chromatogr A. 2009 Nov 13;1216(46):8101-9. doi: 10.1016/j.chroma.2009.04.074. Epub 2009 May 4.
A rapid confirmatory method has been developed and validated for the simultaneous identification, confirmation and quantitation of 11 nitroimidazoles in eggs by liquid chromatography tandem mass spectrometry (LC-MS/MS). The method is validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ), tinidazole (TNZ) and ternidazole (TRZ). MNZ, DMZ and RNZ have been assigned a recommended level (RL) of 3 microg kg(-1) by the Community Reference Laboratory (CRL) in Berlin. The developed method described in this study is easily able to detect all the nitroimidazole compounds investigated at this level and below. Egg samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants.
3.Antiprotozoals effective in vitro against the scuticociliate fish pathogen Philasterides dicentrarchi.
Iglesias R1, Paramá A, Alvarez MF, Leiro J, Sanmartín ML. Dis Aquat Organ. 2002 Jun 3;49(3):191-7.
The histophagous ciliate Philasterides dicentrarchi causes fatal scuticociliatosis in farmed turbot Scophthalmus maximus and sea bass Dicentrarchus labrax. The present study screened 52 candidate antiprotozoals for activity against this pathogen in vitro. Of these compounds, 14 were effective (i.e. killed all ciliates within a 24 h assay period). In descending order of efficacy (minimum lethal concentration 100 to 0.8 ppm), these were niclosamide, oxyclozanide, bithionol sulfoxide, toltrazuril, N-(2'-hydroxy-5'-chloro-benzoyl) 2-chloro-4-nitroaniline, furaltadone, doxycycline hyclate, formalin, albendazole, carnidazole, pyrimethamine, quinacrine hydrochloride and quinine sulfate. Administration in filtered seawater rather than phosphate-buffered saline inactivated doxycycline hyclate and albendazole, and markedly reduced that of bithionol sulfoxide and toltrazuril, suggesting that these compounds may not be effective in bath administration.
4.Development and validation of a rapid method for the determination and confirmation of 10 nitroimidazoles in animal plasma using liquid chromatography tandem mass spectrometry.
Cronly M1, Behan P, Foley B, Malone E, Regan L. J Chromatogr B Analyt Technol Biomed Life Sci. 2009 May 15;877(14-15):1494-500. doi: 10.1016/j.jchromb.2009.03.030. Epub 2009 Mar 25.
A rapid LC-MS/MS method has been developed and validated for the simultaneous identification, confirmation and quantitation of 10 nitroimidazoles in plasma. The method validated in accordance with Commission Decision (CD) 2002/657/EC is capable of analysing for metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ) and ternidazole (TRZ) which are rarely analysed by modern methods. MNZ, DMZ and RNZ have a recommended level (RL) of 3 ng mL(-1) which this method is easily able to detect for all the nitroimidazole compounds. Plasma samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid-liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase.