2 research outputs found
Multiresidue Pesticide Analysis of Dried Botanical Dietary Supplements Using an Automated Dispersive SPE Cleanup for QuEChERS and High-Performance Liquid Chromatography–Tandem Mass Spectrometry
An automated dispersive solid phase extraction (dSPE)
cleanup procedure
as part of the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS)
method, coupled with liquid chromatography–tandem mass spectrometry
using electrospray ionization in positive mode, was used for the simultaneous
analysis of 236 pesticides in three dried powdered botanical dietary
supplements (ginseng, saw palmetto, and gingko biloba). The procedure
involved extraction of the dried powdered botanical samples with salt-out
acetonitrile/water extraction using anhydrous magnesium sulfate and
sodium chloride, followed by an automated dSPE cleanup using a mixture
of octadodecyl- (C<sub>18</sub>) and primary–secondary amine
(PSA)-linked silica sorbents and anhydrous MgSO<sub>4</sub> and online
LC-MS/MS analysis. Dynamic multiple-reaction monitoring (DMRM) based
on the collection of two precursor-to-product ion transitions with
their retention time windows was used for all of the targeted pesticides
and the internal standard. Matrix-matched calibration standards were
used for quantitation, and standard calibration curves showed linearity
(<i>r</i><sup>2</sup> > 0.99) across a concentration
range
of 0.2–400 ng/mL for the majority of the 236 pesticides evaluated
in the three botanical matrices. Mean recoveries (average %RSD, <i>n</i> = 4) were 91 (6), 93 (4), 96 (3), and 99 (3)% for ginseng,
101 (9), 98 (6), 99 (4), and 102 (3)% for gingko biloba, and 100 (9),
98 (6), 96 (4), and 96 (3)% for saw palmetto at fortification concentrations
of 25, 100, 250, and 500 μg/kg, respectively. The geometric
mean matrix-dependent instrument detection limits were 0.17, 0.09,
and 0.14 μg/kg on the basis of the studies of 236 pesticides
tested in ginseng roots, gingko biloba leaves, and saw palmetto berries,
respectively. The method was used to analyze incurred ginseng samples
that contained thermally labile pesticides with a concentration range
of 2–200 μg/kg, indicating different classes of pesticides
are being applied to these botanicals other than the traditional pesticides
that are commonly used and analyzed by gas chromatography techniques.
The method demonstrates the use of an automated cleanup procedure
and the LC-MS/MS detection of multiple pesticide residues in dried,
powdered botanical dietary supplements
Multiresidue Pesticide Analysis of Dried Botanical Dietary Supplements Using an Automated Dispersive SPE Cleanup for QuEChERS and High-Performance Liquid Chromatography–Tandem Mass Spectrometry
An automated dispersive solid phase extraction (dSPE)
cleanup procedure
as part of the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS)
method, coupled with liquid chromatography–tandem mass spectrometry
using electrospray ionization in positive mode, was used for the simultaneous
analysis of 236 pesticides in three dried powdered botanical dietary
supplements (ginseng, saw palmetto, and gingko biloba). The procedure
involved extraction of the dried powdered botanical samples with salt-out
acetonitrile/water extraction using anhydrous magnesium sulfate and
sodium chloride, followed by an automated dSPE cleanup using a mixture
of octadodecyl- (C<sub>18</sub>) and primary–secondary amine
(PSA)-linked silica sorbents and anhydrous MgSO<sub>4</sub> and online
LC-MS/MS analysis. Dynamic multiple-reaction monitoring (DMRM) based
on the collection of two precursor-to-product ion transitions with
their retention time windows was used for all of the targeted pesticides
and the internal standard. Matrix-matched calibration standards were
used for quantitation, and standard calibration curves showed linearity
(<i>r</i><sup>2</sup> > 0.99) across a concentration
range
of 0.2–400 ng/mL for the majority of the 236 pesticides evaluated
in the three botanical matrices. Mean recoveries (average %RSD, <i>n</i> = 4) were 91 (6), 93 (4), 96 (3), and 99 (3)% for ginseng,
101 (9), 98 (6), 99 (4), and 102 (3)% for gingko biloba, and 100 (9),
98 (6), 96 (4), and 96 (3)% for saw palmetto at fortification concentrations
of 25, 100, 250, and 500 μg/kg, respectively. The geometric
mean matrix-dependent instrument detection limits were 0.17, 0.09,
and 0.14 μg/kg on the basis of the studies of 236 pesticides
tested in ginseng roots, gingko biloba leaves, and saw palmetto berries,
respectively. The method was used to analyze incurred ginseng samples
that contained thermally labile pesticides with a concentration range
of 2–200 μg/kg, indicating different classes of pesticides
are being applied to these botanicals other than the traditional pesticides
that are commonly used and analyzed by gas chromatography techniques.
The method demonstrates the use of an automated cleanup procedure
and the LC-MS/MS detection of multiple pesticide residues in dried,
powdered botanical dietary supplements