Determination of chloramphenicol in muscle using a particle beam interface for combining liquid chromatography with negative-ion chemical ionization mass spectrometry.

A simple and rapid liquid chromatographic-mass spectrometric analysis of chloramphenicol in calf muscle is presented. A particle beam interface was used, with negative-ion chemical ionization mass spectrometry using methane as the reagent gas. The method specificity was tested for three related compounds, dehydrochloramphenicol, nitrosochloramphenicol and nitrophenylaminopropanediol. The extraction procedures require 5 g of muscle, and the quantification limit is 2 micrograms/kg for chloramphenicol. Residues were detected in calf muscle 48 h after intravenous administration of chloramphenicol (25 mg/kg body weight).