Chlortetracycline confirmation

Quantification and confirmation of tetracycline, oxytetracycline, and chlortetracycline residues in milk (84) as well as chloramphenicol residues in calf muscle (85) have been also carried out using LC-PB-NCI-MS. Use of an SIM mode allowed a detection limit of about 100 ppb for the tetracyclines and 2 ppb for chloramphenicol residues. 

P.J. Kijak, M.G. Leadbetter, M.H. Thomas, E.A. Thomson, Confirmation of oxytetracycline, tetracycline and chlortetracycline residues in milk by particle-beam liquid chromatography-mass spectrometry, Biol. Mass Spectrom., 20 (1991) 789. 

Similar results were found in 16 other patients taking various combinations of phenytoin, carbamazepine, primidone or phenobarbital. The serum doxycycline levels of almost all of them fell below 0.5 micrograms/mL during the 12 to 24 hour period following their last dose of doxycycline 100 mg. Tetracycline, methacycline, oxytetracycline, demeclocycline and chlortetracycline levels were not significantly affected by these antiepilepties. Other studies confirm this interaction between some barbiturates (amobarbital, pentobarbital, phenobarbital) and doxycycline. ... 

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