Fumonisin B1 analysis with capillary electrophoresis-electrospray ionization mass spectrometry

Fumonisin B1, a mycotoxin produced by a common fungal contaminant of corn, Fusarium moniliforme, was analyzed by capillary electrophoresis-electrospray ionization mass spectrometry. System performance was maximal with uncoated columns. System efficiencies of approximately 44,000 plates/m and reproducible analysis times of about 13 min were obtained. System efficiency with methyl-coated columns was approximately 24,000 plates/m. Reproducible analysis times of about 3.5 min were obtained with these columns. With uncoated columns, the concentration limit of detection was 156 ppb with a s/n ratio of approximately 10. The estimated injected mass at 156 ppb was 1.1 pg. Repeated injections of extracts containing constant fumonisin B1 concentrations showed that peak areas were slightly inconsistent, although generally similar to variations encountered with liquid chromatography-electrospray ionization mass spectrometry. The source of this inconsistency was traced to sample solubility, errors inherent in electrophoresis injections, and electrospray instability. Minimizing these problem areas will produce a technique with peak area reproducibilities comparable to liquid chromatography-electrospray ionization mass spectrometry, but with potentially greater resolving power.