AOAC SPIFAN Nutrients ERP-Final Review (Jan. 2019)

2017.03 (JULY 2018) Amino-02 Tryptophan by enz hyd_Abbott Labs_Method

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

GUsing 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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