2
repeatability standard deviation (SD
r
); or % repeatability relative standard deviation
48
(%RSD
r
).
49
50
Reproducibility
51
The standard deviation or relative standard deviation calculated from among-laboratory
52
data. Expressed as the reproducibility relative standard deviation (SD
R
); or % reproducibility
53
relative standard deviation (% RSD
R
).
54
55
Vitamin B
2
(riboflavin)
56
An isoalloxazine ring (
flavin
ring) substituted at the 10 position with a D-ribityl side chain.
57
Flavin mononucleotide (FMN) consists of a flavin ring phosphoryled at the 5’ position of the
58
ribityl side chain. CAS number
Flavin adenine dinucleotide (FAD) consists of
59
an FMN unit with an additional adenosine-5’-monophosphate. CAS number:
146-14-5.
FAD
60
is the principle form of B
2
in biological material.
61
62
63
64
Figure 1: Chemical structure of riboflavin
65
66
4.
Method Performance Requirements:
67
68
Analytical range
40 – 350*
Limit of Quantitation (LOQ)
≤ 40*
Accuracy
± 40%
Repeatability (RSD
r
)
≤ 14%
Reproducibility (RSD
R
)
≤ 20%
Concentrations apply to: a) ‘ready-to-feed” liquids “as is”; b) re-
constituted powders (25 g into 200 g of water); and c) liquid
concentrates diluted 1:1 by weight.
*μg /100 g reconstituted final product.
69
70
