Pyrrolizidine

alkaloids (PAs) and their N

-

oxides (PANOs) have serious hepatotoxic

effects in both humans and animals, necessitating a method capable of detecting,

characterizing, and quantifying them using a robust assay. While triple quadrupole

LC/MS systems are ideal

for targeted detection, targeted analysis requires

standards that are not always easily obtained. Only a fraction of known naturally

occurring PAs are available as standards. Triple quadrupole analyses are also not

useful for screening unknowns. High

-

res

olution mass spectrometers that provide

accurate

-

mass data enable characterization of unknown PAs/PANOs without the

need for specific standards.

This application note presents a workflow that uses accurate

-

mass Q

-

TOF LC/MS,

with All Ions MS/MS and databas

e/mass spectral library searching, for the

selective and sensitive characterization, screening, tentative identification, and

quantification of PAs and PANOs in botanicals and dietary supplements.

Twenty

-

five PA/PANO standards were characterized using

their high

-

resolution

accurate

-

mass MS/MS spectra. These data were used to create a personal com

-

pound database and library (PCDL) that was then used to screen for PAs/PANOs in

44 botanical and dietary supplement samples. Quantitation was performed using

Q

-

TOF LC/MS response. PAs/PANOs not specifically targeted were tentatively

identified using characteristic fragment ions and fragmentation patterns. The

PAs/PANOs characterized could potentially lead to the discovery of more unique

PAs in additional botan

ical and dietary supplement sample

s.