Analysis of Saxitoxin from Urine Using Continuous Flow Fast Atom Bombardment andElectrospray Ionization Mass Spectrometry

摘要

A method of analysis for saxitoxin (STX) in the rat (blood serum and urine) andhuman urine was developed using CBA and EMPORE columns followed by oxidation with hydrogen peroxide and analysis by HPLC using a C18 reversed phase column and detection by fluorescence of the OPA derivative. Detection was also made by continuous flow fast atom bombardment (CF/FAB/MS). STX was found in the serum and urine of rats treated with STX (1 to 3 microns g total intraperitoneal injection) as soon as 10 min after dosing and up to 8 hrs. Rats dosed with 75 microns g by stomach intubation had detectable amounts of STX in their urine for up to 31 hrs. Confirmation was done by CF/FAB/MS using selected ion monitoring (m/z+ 300 282). The limit of detection by HPLC was 4 ppb in human urine and 220 ppb in rat urine. The limit of detection by CF/FAB/MS was 25 ppb in human urine. A method of analysis using EMPORE column technology yielded a percent recovery of 102 at 25 ppb and 99 at 50 ppb. CBA columns used for comparison gave a percent recovery that varied between 64 and 90%.