An Enhanced GC/MS Procedure for the Identification of Proteins in Paint Microsamples
Table 2
Linear correlation coefficients (r2).
Amino acid
Quantitation ion (m/z)
Retention time (min)
Py
DMF
a
b
Correlation coefficient (r2)
LOD (ng)
LOQ (ng)
a
b
Correlation coefficient (r2)
LOD (ng)
LOQ (ng)
Ala
158 (100)
10.81
0.003
0.484
0.9666
0.126
0.421
0.003
0.508
0.9973
0.028
0.094
Gly
218 (76)
11.59
0.001
0.376
0.9836
0.115
0.382
−0.041
0.355
0.9882
0.056
0.188
Val
186 (100)
12.78
−0.013
0.613
0.9672
0.190
0.632
0.003
0.616
0.9977
0.030
0.102
Leu
200 (100)
13.42
−0.004
0.677
0.9432
0.201
0.670
−0.007
0.665
0.9986
0.031
0.103
Ile
200 (100)
14.10
−0.006
0.616
0.9631
0.198
0.661
0.003
0.617
0.9981
0.034
0.114
Pro
184 (100)
15.49
−0.009
0.647
0.8909
0.174
0.580
−0.03
0.795
0.9963
0.046
0.154
Ser
288 (100)
18.23
−0.001
0.273
0.9251
0.163
0.543
−0.002
0.43
0.9923
0.056
0.187
Met
292 (83)
19.21
0.003
0.225
0.9595
0.234
0.780
−0.011
0.221
0.9957
0.061
0.203
Phe
302 (100)
21.24
−0.004
0.324
0.9528
0.255
0.850
−0.004
0.331
0.9969
0.059
0.195
Asp
302 (100)
21.42
0.002
0.276
0.9656
0.272
0.905
0.002
0.333
0.8017
0.241
0.804
Hyp
314 (100)
21.55
0.001
0.107
0.7197
0.411
1.369
0.007
0.588
0.9555
0.168
0.561
Glu
432 (100)
23.23
−0.015
0.319
0.9873
0.457
1.522
0.004
0.334
0.8224
0.372
1.241
Note. Linear correlation coefficients (r2), LOD and LOQ of amino acids were derivatized using Py or DMF as solvent. Number in parentheses indicate % relative intensity of ions; correlation coefficients obtained from linear regression analysis of calibration curve.
