6. AOACSPIFANMethods-2018Awards

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Data Obtained From Integrator

Sample

TRP Conc. IS Conc.

Amount Ratio 10.1737 50.8684 255.583 508.685

TRP Area

IS Area

Area Ratio

Very Low

0.410/0.0403 2.05/0.0403 10.3/0.0403 20.5/0.0403

7405.8 36760 185145 372353 105717

102989 102281 103407 103277

0.071909

Low Mid High

0.3594 1.7904 3.6054 1.0718 0.1154

Sample

98633 98097

Blank

11323

Tryptophan Standard weight = 0.0103 grams 5-methyl-DL-tryptophan (Int Std.) = 0.0403 grams 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

TRP (mg/L)

 IS Amount

Slope

For Sample:

= 1.0718 – (- 0.004522)  0.0403

TRP mg

L 0.007082

Tryptophan in sample = 6.125 mg/L

For Blank:

Blank mg = 0.1154 – (-0.004522)  0.0403 L 0.007082

Tryptophan in Blank = 0.6824 mg/L

Tryptophan Value in g/100g of sample: