OMB Meeting Book_9-11-14

Lab 5: The method performs to stated applicability and “works exactly how it is written”. There are no

recommendations to amend the AOAC method and no safety concerns. However, the “only major

observation we had was around the importance of the specified pH values. We did a miniature experiment

around the pH of Mobile Phase A and found if the pH was higher, 0.3 pH units, than the specified value then

the elution sequence changed for AMP and TMP. Usually TMP will elute just before AMP however this was

the other way around when the pH was higher and the elution times were extended by approximately 0.5

minutes.”

Lab 7: Some concerns expressed about the value of the extinction coefficient for CMP. Follow-up work may

be needed.

Lab 9: There are no specific safety concerns. The method performs to stated applicability and there are no

concerns about method’s reproducibility. Suggest adding “centrifuge of 8000 rpm/min 5 min at 4 °C before

anion-exchange procedure.” Problems were found with starch-based samples.

Lab 10: The method performs to stated applicability, “however, UMP accuracy in some product matrices is

around the 90% lower SMPR limit”. No safety concerns with method. “We recommend a decrease in the

amount of sample loaded onto the SPE column to the extent that the SRM gives accurate recoveries and

the method is then more universally applicable to varied product matrices”.

Conclusions

A multi-laboratory collaborative study of AOAC First Action 2011.20, an HPLC-UV method for the analysis of

nucleotides in infant formula, was undertaken. The method was applied to a number of different infant

formula matrices and demonstrated acceptable precision for nucleotide supplemented infant formulas.

Recommendations

On the basis of the results of this study, it is recommended that AOAC First Action 2011.20 be endorsed as

Final Action for the determination of adenosine 5′-monophosphate (AMP), cytidine 5′-monophosphate

(CMP), guanosine 5′-monophosphate (GMP), inosine 5′-monophosphate (IMP), and uridine

5′-monophosphate (UMP) in infant formula and be entitled: AOAC Official Method 2011.20 Nucleotides in

Infant Formula.

Acknowledgements

I am grateful to the following collaborators and their colleagues for their participation in this study:

Greg Jaudzems, Nestlé, OH, USA

George Joseph, AsureQuality, Auckland, New Zealand

Sabine Meng Jensen, Eurofins; Vejen, Denmark

Sam Murray and Paul McNabb, Cawthron Institute, Nelson, New Zealand

Sheila Saldo and Holly Huo, Fonterra, Waitoa, New Zealand

Steve Tennyson and Scott Christiansen; Perrigo Nutritionals, Georgia, VT, USA

Collaborative Study Report: Method 2011.20 Nucleotides by HPLC-UV

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