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© 2015 AOAC INTERNATIONAL
J. Internal Control Plan
QC samples (certified,
P
-test, in-house reference samples,
or spiked samples) must be regularly included and analyzed in
duplicate.
Spiked experiment
.—Spike the test portion with 20 µL (for
powdered matrices) or 100 µL (for liquid matrices) of standard
working solution 0.05 µg/mL,
C
(
d
), at the same time as the IS is
added,
E
(
a
). This corresponds to 10 µg/kg spiking level. Calculate
the recovery rate (Rec) of the spiked sample using the following
equation:
100
Re
×
−
=
Spiked
N
T
c
ρ
ρ
ρ
where ρ
T
is the total concentration of sodium fluoroacetate
measured in the spiked sample in micrograms per kg. ρ
N
is the
native concentration of sodium fluoroacetate measured in the
nonspiked sample in micrograms per kg. ρ
Spiked
is the concentration
of sodium fluoroacetate spiked in the sample in micrograms per kg
(calculated value).
The recovery rate should be between 70–120% when spiked at
the 1 µg/kg level.
References: (1) Commission Decision 2002/657/EC of 12 August
2002 implementing Council Directive 96/23/EC
concerning the performance of analytical methods
and the interpretation of results,
Off. J. Eur. Commun.
(2002)
L221
, 8–36.
http://eur-lex.europa.eu/legal- content/EN/TXT/F/?uri=CELEX:32002D0657&rid=1(2) SANCO/12571/2013: Guidance document on
analytical quality control and validation procedures
for pesticide residues analysis in food and feed,
http://ec.europa.eu/food/plant/pesticides/guidance_documents/docs/qualcontrol_en.pdf
J. AOAC Int. 98 , 1127(2015)DOI: 10.5740/jaoac.int.2015.03
AOAC SMPR 2015.001
J. AOAC Int. 98 , 1092(2015)DOI: 10.5740/jaoac.int.SMPR2015.001
Posted: October 16, 2015
Table 2015.03G. Performance characteristics
Sample
Recovery, %
a
CV(r), %
CV(iR), %
1 µg/kg 10 µg/kg
1 µg/kg
10 µg/kg
1 µg/kg
10 µg/kg
Milk-based formula
134
105
6
3
11
4
Soy-based formula
117
103
6
2
8
3
Partially Hydrolyzed milk-based formula
111
108
4
5
9
4
Partially hydrolyzed soy-based formula
116
103
9
2
8
2
High-fat nutritional formula
112
101
4
3
7
4
High-protein nutritional formula
96
99
4
2
6
2
a
Recovery data for sodium fluoroacetate were calculated from values obtained under intermediate reproducibility conditions.
Candidates for 2016 Method of the Year
38