Optimization of the analytical performance of the magnetic sector mass spectrometer for the identification of residual chloramphenicol in shrimp

Abstract

Chemical noise limits mass spectrometric detection of chloramphenicol (CAP) with electron capture ionization at low resolution, and makes CAP identification at concentrations of 5 parts per billion (ppb) difficult. Increasing the resolution from 1000 to 3500, however, was sufficient to separate the analyte signals from the noise signals, and resulted in a 100 times higher analytical sensitivity. The introduction of sweep gas in the ion source decreased the scattering of the quantitative results on average by a factor of 7, and thereby improved the precision of the analyses to an acceptable level (CV < 10%). Under such conditions, CAP residues of 1.5 and 2.1 ppb in shrimp as determined by electron capture gas chromatography/mass spectrometry can readily be identified by monitoring four diagnostic ions.

Development of a Rapid and Sensitive SPE-LC-ESI MS/MS Method for the Determination of Chloramphenicol in Seafood

“…A number of LC methods have been reported (14)(15)(16) in the literature for the determination of CAP in seafood samples using either a UV or a UV- (17). Various analytical methods have been developed for the determination of CAP by using gas chromatography employing either electron capture (18,19) or mass spectrometric detection as trimethylsilyl derivatives (20)(21)(22). However, derivatization techniques, in general, are not preferred for residue analysis because they are time-consuming and not reproducible in trace levels.…”

“…However, these techniques do not fulfill the criteria established by Commission Decision 93/256/EEC for methods used for regulatory purposes, as this states “methods based only on chromatographic analysis without the use of molecular spectrometric detection are not suitable for use as confirmatory methods” (). Various analytical methods have been developed for the determination of CAP by using gas chromatography employing either electron capture ( , ) or mass spectrometric detection as trimethylsilyl derivatives ( − ). However, derivatization techniques, in general, are not preferred for residue analysis because they are time-consuming and not reproducible in trace levels.…”