AOAC OMA# 2017.03 (Final Action)-OMB

2017.03 (JAN 2019) Amino-02-(ERP Review for Pubs) Tryptophan by enz hyd_Abbott Labs_Method_10172018

FOR ERP USE ONLY DO NOT DISTRIBUTE

HPLC Determination of Total Tryptophan in Infant Formula and Adult/Pediatric Nutritional Formula Following Enzymatic Hydrolysis Jonathan Draher and Norman White Abbott Nutrition, Division of Abbott Laboratories ALIMENTUM RTF Sample Weight = 1.0095 grams Using a scientific pocket calculator, obtain the linear regression parameters utilizing the amount ratio vs. area ratio for the standards. Thus, the linear regression parameters obtained for the example listed above are: Correlation Intercept Slope 0.99998 -0.004522 0.007082

To find the concentration of the sample and the blank (using linear regression data) use the following formula:

= Peak Area Ratio - Intercept × IS Amount Slope

TRP (mg/L)

For Sample:

= 1.0718 – (- 0.004522) × 0.0403

TRP mg

L 0.007082 Tryptophan in sample = 6.125 mg/L

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