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Single Laboratory Validation – AOAC First Action Method 2012.22 Vitamin C in Infant Formula and Adult/Pediatric
Nutritional Formula by UPLC-UV
Date of Issue: February 14
th
, 2013
RDLS-RD130018
E.Campos Giménez (NRC/QS, Lausanne)
Page 5
Validation Protocol
SLV
Guidelines
SPIFAN SLV recommended guidelines were followed (Attachment 1).
System
suitability
Replicate (6) injections of a working standard solution (1 µg/mL) were performed
before each analytical series. Relative standard deviation of retention time and
response was calculated.
Specificity
The five placebo samples supplied with the SPIFAN test material kit were
analyzed.
Linearity/
Calibration Fit
Three independent stock solutions of ascorbic acid were prepared at a
concentration 500 µg/mL. Working solutions at nine levels covering the range
0.1-10 µg/mL were prepared by diluting the stock solutions and injected for
linearity demonstration. Seven levels (0.5-10 µg/mL) were used for daily
calibration.
LOD/LOQ
Ten independent analysis of a non fortified sample (Infant Formula RTF Milk
Based) spiked with low concentrations of ascorbic acid were used for
determination of LOD/LOQ.
Precision
studies
All samples in the kit were used for precision studies. They were analyzed in
duplicate on 7 different days by 2 analysts. Fresh reagents and working
standards were prepared each day.
Accuracy
(trueness)
Reference material
: SRM 1849a was analyzed in duplicate on 6 different
days by 2 analysts. Overall mean was calculated and compared to certified
value (78.4 ± 6.5 mg/100 g).
Spike recovery
: The five placebo samples were spiked at 2 levels (50 % and
100 % of target value). Spiked and non spiked samples were analyzed in
duplicate on 3 different days by 2 different analysts.
Reference
sample
An internal reference sample from Nestlé Proficiency Testing was used as
control sample in each series of analysis.
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VitC-03/2012.22
For ERP Use Only
DO NOT DISTRIBUTE
AOAC OMB Meeting Book
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