4 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
Effect of Processing on Recovery and Variability Associated with Immunochemical Analytical Methods for Multiple Allergens in a Single Matrix: Dark Chocolate
Immunodetection of allergens in dark chocolate is complicated
by
interference from the chocolate components. The objectives of this
study were to establish reference materials for detecting multiple
allergens in dark chocolate and to determine the accuracy and precision
of allergen detection by enzyme-linked immunosorbent assay (ELISA)
before and after chocolate processing. Defatted peanut flour, whole
egg powder, and spray-dried milk were added to melted chocolate at
seven incurred levels and tempered for 4 h. Allergen concentrations
were measured using commercial ELISA kits. Tempering decreased the
detection of casein and β-lactoglobulin (BLG), but had no significant
effect on the detection of peanut and egg. Total coefficients of variation
were higher in tempered than untempered chocolate for casein and BLG,
but total and analytical CVs were comparable for peanut and egg. These
findings indicate that processing has a greater effect on recovery
and variability of casein and BLG than peanut and egg detection in
a dark chocolate matrix
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
Effect of Processing on Recovery and Variability Associated with Immunochemical Analytical Methods for Multiple Allergens in a Single Matrix: Sugar Cookies
Among the major food allergies, peanut, egg, and milk
are the most
common. The immunochemical detection of food allergens depends on
various factors, such as the food matrix and processing method, which
can affect allergen conformation and extractability. This study aimed
to (1) develop matrix-specific incurred reference materials for allergen
testing, (2) determine whether multiple allergens in the same model
food can be simultaneously detected, and (3) establish the effect
of processing on reference material stability and allergen detection.
Defatted peanut flour, whole egg powder, and spray-dried milk were
added to cookie dough at seven incurred levels before baking. Allergens
were measured using five commercial enzyme-linked immunosorbent assay
(ELISA) kits. All kits showed decreased recovery of all allergens
after baking. Analytical coefficients of variation for most kits increased
with baking time, but decreased with incurred allergen level. Thus,
food processing negatively affects the recovery and variability of
peanut, egg, and milk detection in a sugar cookie matrix when using
immunochemical methods