Mass spectrometric analysis of anatoxin-a

Secondary ion mass spectrometry (SIMS), gas chromatography/mass spectrometry (GC/MS), desorption chemical ionization/mass spectrometry (DCI/MS), and thermospray/mass spectrometry (TSP/MS) were evaluated for the detection of a low-molecular weight biological toxin, anatoxin-a. The lowest detection limit was obtained using isobutane or ammonia DCI/MS. Tandem mass spectrometry (MS/MS) was used to enhance the selectivity and sensitivity of the analysis. The detection limit for the pure material is 10 pg, and 100 pg of the toxin can be analyzed directly from urine using DCI/MS/MS.