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AOAC Official Method 2016.16
Curcuminoids in Turmeric
Liquid Chromatography with UV-Vis Detection
First Action 2016
(Applicable to the determination of curcumin, demethoxycurcumin and bisdemethoxycurcumin
in turmeric (
Curcuma longa
Linn) rhizomes, dietary ingredients and dietary supplement products
containing turmeric alone or in combination with other dietary ingredients.)
Caution:
Solvents utilized are common-use solvents. Refer to adequate manuals
or Material Safety Data Sheets (MSDS) to ensure that the safety
guidelines are applied before using chemicals. Store in a flammable
liquid storage cabinet. Harmful if inhaled, swallowed, or absorbed
through the skin. Use appropriate personal protective equipment such
as a laboratory coat, safety glasses, rubber gloves, and a fume hood.
Dispose of all materials according to federal, state, and local
regulations.
See
Table
2016.16A
for method performance data supporting acceptance of the method.
A. Principle
Samples are extracted with methanol using a wrist-action shaker. Dilution of highly
concentrated samples may be required prior to LC analysis. Quantitation is performed with
external calibration against reference standards for curcumin, demethoxycurcumin and
bisdemethoxycurcumin.
B. Apparatus
(
a
)
Analytical balance.-
Sensitive to at least 0.0001 g.
(
b
)
Grinder.-
Retsch or equivalent centrifugal mill fitted with a 0.25 mm screen.
(
c
)
Volumetric pipet.-
Class A, 25 mL.
(
d
)
Centrifuge tubes.-
Conical polypropylene tubes, 50 mL.
(
e
)
Vortex mixer.
(
f
)
Centrifuge.-
Benchtop with rotor for 50 mL conical tubes, maximum 21,000 x
g
.
(
g
)
Shaker.-
Wrist action.
(
h
)
Micropipettors.-
Capable of pipetting 200 and 1000 μL.
(
i
)
LC vials with caps.
(
j
)
Volumetric flasks.-
Class A, 10 mL.
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