N
X
C
O
N
S
Hal
Solvents
Natural
Products
P Si
C
C
C C
C
C
440
8 Mass Spectrometry
Matrix Compounds in Negative Ionization FAB Mass Spectra
3-Nitrobenzyl alcohol (M r 153.1)
Glycerol (M r 92.1)
2-Nitrophenyl octyl ether (M r 251.3)
2-Nitrobenzyl alcohol solution of hexadecylpyridinium bromide (M r 384.4;
enhances detectability and reduces metal ion adducts of sample [3])
100
50
0
400
350
300
250
200
150
100
50
0
100
50
0
1000
950
900
850
800
750
700
650
600
550
500
500
450
400
122 138
352
199
153
306
459
612
46
168
765
100
50
0
250
200
150
100
50
0
50
25
0
1000
950
900
850
800
750
700
650
600
550
500
50
30
10
500
450
400
350
300
250
71
59
91
183
275
367
459
551
643
735
100
50
0
250
200
150
100
50
0
100
50
0
1000
950
900
850
800
750
700
650
600
550
500
500
450
400
350
300
250
25
46
108
93
235
502
470
153
138
122
251
266
297
518
100
50
0
250
200
150
100
50
0
100
50
0
1000
950
900
850
800
750
700
650
600
550
500
500
450
400
350
300
250
25
79
845
462