AOAC OMB Final Action Recommendation (December 2019)-2016.14

2016.14 (Jan. 2019) FOS-03 MLT Report FOR ERP USE ONLY DO NOT DISTRIBUTE

Table 13. Elution program used by lab 12

Flow rate, mL/min

Water, % A

250 mM NaOH, % B

650 mM NaOAc, % C

Time, min

0

1.0 1.0 1.0 1.0 1.0 1.0 1.0

90 90 70 30 30 90 90

10 10 30 30 30 10 10

0 0 0

12 15 22 24 26 35

40 40

0 0

a) Standard solution Level 4

b) Child formula powder

Figure 7. Example of chromatograms obtained by lab 12, using PA1 column (4 x 250 mm) without post- column addition of NaOH and elution program described in Table 13

Conclusions The performance of the method largely meets the requirements of the SMPR and has demonstrated excellent resilience to adaptations made by the MLT participants.