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Table 2 ESI-MS/MS conditions for quantitation of FAA in milk

From: Use of UPLC-ESI-MS/MS to quantitate free amino acid concentrations in micro-samples of mammalian milk

Compound number Amino acid/ labeled amino acid MRM transition (m/z) Cone voltage (V) Collision energy (eV) Rt (min) Function Window time (min)* Internal standard
1 L-Histidine 326.21 >171 35 19 1.33 1 1.1 – 2.0 2
2 L-[2-15 N3]Histidine 329.21 > 171 35 19 1.33 1 1.1 – 2.0  
3 Taurine 296.11 > 171 32 24 1.76 1 1.1 – 2.0 4
4 [15 N]Taurine 297.11 > 171 32 24 1.76 1 1.1 – 2.0  
5 L-Serine 276.11 > 171 27 19 2.12 2 1.9 – 3.4 6
6 L-[2-15 N]Serine 277.11 > 171 27 19 2.12 2 1.9 – 3.4  
7 L-Glutamine 317.14 > 171 35 20 2.26 2 1.9 – 3.4 8
8 L-[2-15 N]Glutamine 318.14 > 171 35 20 2.26 2 1.9 – 3.4  
9 L-Arginine 345.21 > 171 35 19 2.34 2 1.9 – 3.4 10
10 L-[1-13C]Arginine 347.21 > 171 35 19 2.34 2 1.9 – 3.4  
11 Glycine 246.16 > 171 33 20 2.47 2 1.9– 3.4 12
12 L-[1-13C]Glycine 247.16 > 171 33 20 2.47 2 1.9 – 3.4  
13 L-Aspartic acid 304.11 > 171 32 24 2.78 2 1.9 – 3.4 14
14 L-[2-15 N]Aspartic Acid 305.11 > 171 32 24 2.78 2 1.9 – 3.4  
15 L-Glutamic acid 318.11 > 171 32 24 3.62 3 3.4 – 6.0 16
16 L-[2-15 N]Glutamic Acid 319.11 > 171 32 24 3.62 3 3.4 – 6.0  
17 L-Citrulline 346.21 > 171 32 24 3.72 3 3.4 – 6.0 18
18 L-[2-15 N]Citrulline 347.21 > 171 32 24 3.72 3 3.4 – 6.0  
19 L-Threonine 291.11 > 171 31 22 4.30 3 3.4 – 6.0 20
20 L-[2-15 N]Thréonine 291.11 > 171 31 22 4.30 3 3.4 – 6.0  
21 L-Alanine 260.00 > 171 32 25 4.76 3 3.4 – 6.0 22
22 L-[1-13C]Alanine 261.00 > 171 32 25 4.76 3 3.4 – 6.0  
23 L-Proline 286.16 > 171 29 21 5.37 3 3.4 – 6.0 22
24 L-Cystine 291.18 > 171 32 24 6.50 4 6.2 – 7.5 31
25 L-Tyrosine 352.21 > 171 32 24 6.61 4 6.2 – 7.5 26
26 L-[2-15 N]Tyrosine 353.21 > 171 32 24 6.61 4 6.2 – 7.5  
27 L-Lysine 487.11 > 171 32 24 6.63 4 6.2 – 7.5 28
28 L-[13C6]Lysine 493.23 > 171 32 24 6.63 4 6.2 – 7.5  
29 L-Methionine 320.21 > 171 32 24 6.80 4 6.2 – 7.5 31
30 L-Valine 288.23 > 171 35 24 6.98 4 6.2 – 7.5 31
31 L-[1-13C]Valine 289.23 > 171 35 24 6.98 4 6.2 – 7.5  
32 L-Isoleucine 302.20 > 171 39 35 7.85 5 7.5 – 8.5 34
33 L-Leucine 302.20 > 171 39 35 7.94 5 7.5 – 8.5 34
34 L-[2-15 N]Leucine 303.20 > 171 39 35 7.94 5 7.5 – 8.5  
35 L-[2H5]Phenylalanine 341.21 > 171 32 24 8.01 5 7.5 – 8.5  
36 L-Phenylalanine 336.21 > 171 32 24 8.04 5 7.5 – 8.5 35
37 L-[2H5]Tryptophan 380.23 > 171 32 24 8.10 5 7.5 – 8.5  
38 L-Tryptophan 375.23 > 171 32 24 8.13 5 7.5 – 8.5 37
  1. *Note: Before 1.10 min and after 8.50 min the flow state was in waste.