AOAC_SPDS_ERP_-_Set_3

2. Does the method contain system suitability tests or controls as specified by the SMPR? If not, please indicate if there is a need for such tests or controls and which ones. 3. Is there information demonstrating that the method system suitability tests and controls as specified in the SMPR worked appropriately and as expected? If no, please specify. 4. Based on the supporting information, is the method written clearly and concisely? If no, please specify the needed revisions. 5. Based on the supporting information, what are the pros/strengths of the method? 6. Based on the supporting information, what are the cons/weaknesses of the method?

yes

yes

yes

1. appears to be a simple straight forward HPLC gradient separation with UV detection 2. baseline resolution for all analytes 3. appropriate system suitability included 4. addressing the potential for analyte degradation by inclusion of EDTA in mobile phase and diluent

1. only includes caffeine of the 3 methyl xanthenes; could it be extended to include theobromine and thophylline?

7. Any general comments about the method?

method specifies Ascentis Phenyl 3um 100x3.0mm column; would other Phenyl columns also work to give equivalent results? This would give users some flexibility in column selection

Do you recommend this method be adopted as a First Action and published in the Official Methods of Analysis of AOAC INTERNATIONAL? Please specify rationale.

yes method applicable to catechins and caffeine per SMPR for Tea