FUMONISIN B-1 ANALYSIS WITH CAPILLARY ELECTROPHORESIS ELECTROSPRAY-IONIZATION MASS-SPECTROMETRY

Fumonisin B-1, a mycotoxin produced by a common fungal contaminant of corn, Fusarium moniliforme, was analyzed by capillary electrophoresis- electrospray ionization mass spectrometry. System performance was maxi mal with uncoated columns. System efficiencies of approximately 44 000 plates/m and reproducible analysis times of about 13 min were obtaine d. System efficiency with metayl-coated columns was approximately 24 0 00 plates/m. Reproducible analysis times of about 3.5 min were obtaine d with these columns. With uncoated columns, the concentration limit o f detection was 156 ppb with a s/n ratio of approximately 10. The esti mated injected mass at 156 ppb was 1.1 pg. Repeated injections of extr acts containing constant fumonisin B-1 concentrations showed that peak areas were slightly inconsistent, although generally similar to varia tions encountered with liquid chromatography-electrospray ionization m ass spectrometry. The source of this inconsistency was traced to sampl e solubility, errors inherent in electrophoresis injections, and elect rospray instability. Minimizing these problem areas will produce a tec hnique with peak area reproducibilities comparable to liquid chromatog raphy-electrospray ionization mass spectrometry, but with potentially greater resolving power.