Contaminants
observed in LC-MS background |
||||
m/z |
Accurate
Mass (Da) |
Mode |
Compound |
Ion |
42 |
42.0338 |
+ |
Acetonitril |
(M+H)+ |
59 |
59.0604 |
+ |
Acetonitril + Ammonia |
(M+NH4)+ |
64 |
64.0158 |
+ |
Acetonitril + Sodium |
(M+Na)+ |
65 |
65.0597 |
+ |
Methanol |
(2M+H)+ |
79 |
79.0212 |
+ |
DMSO |
(M+H)+ |
83 |
83.0604 |
+ |
Acetonitrile |
(2M+H)+ |
101 |
101.0032 |
+ |
DMSO +
Sodium |
(M+Na)+ |
102 |
102.1277 |
+ |
Triethylamine (TEA) |
(M+H)+ |
105 |
105.0423 |
+ |
Acetonitrile + Sodium |
(2M+Na)+ |
120 |
120.0478 |
+ |
DMSO + Acetonitril |
(M+H+CH3CN)+ |
142 |
142.0297 |
+ |
DMSO + Acetonitril |
(M+Na+CH3CN)+ |
122 |
122.0812 |
+ |
Tris (HOCH2)3CNH2 |
(M+H)+ |
123 |
123.0917 |
+ |
Dimethylaminopyridine (DMAP) |
(M+H)+ |
130 |
130.1590 |
+ |
Diisopropylethylamine (DIPEA) |
(M+H)+ |
144 |
144.1747 |
+ |
Tripropylamine (TPA) |
(M+H)+ |
146 |
146.0689 |
+ |
Acetonitrile + Sodium |
(3M+Na)+ |
150 |
150.1277 |
+ |
Pphenyldiethylamine |
(M+H)+ |
153 |
153.1386 |
+ |
1,8-diazabicyclo[5.4.0]undec-7-ene
(DBU) |
(M+H)+ |
157 |
157.0351 |
+ |
DMSO |
(2M+H)+ |
159 |
158.9640 |
+ |
Sodium trifluoroacetate |
(M+Na)+ |
179 |
179.0171 |
+ |
DMSO +
Sodium |
(2M+Na)+ |
186 |
186.2216 |
+ |
Tributylamine |
(M+H)+ |
214 |
|
+ |
unidentified
contaminant, maybe related to methanol |
(M+H)+ |
225 |
225.1961 |
+ |
Dicyclohexyl urea (DCU) (C13H24N2O) |
(M+H)+ |
239/241 |
|
+ |
Triethylamine |
[(M.HCl)2-Cl]+ |
242 |
242.2842 |
+ |
Ttetrabutylammonium (C4H9)4N+ |
M+ |
243 |
243.1168 |
+ |
Trityl cation |
M+ |
235 |
235.0491 |
+ |
DMSO |
(3M+H)+ |
257 |
257.0310 |
+ |
DMSO |
(3M+Na)+ |
273 |
273.1274 |
+ |
Monomethoxytrityl cation (MMT) |
M+ |
279 |
279.1591 |
+ |
Dibutylphthalate (plasticiser) |
(M+H)+ |
282 |
282.2793 |
+ |
Oleamide |
(M+H)+ |
301 |
301.1410 |
+ |
Dibutylphthalate (plasticiser) + Sodium |
(M+Na)+ |
317 |
317.1150 |
+ |
Dibutylphthalate (plasticiser) + Potassium |
(M+K)+ |
338 |
338.3417 |
+ |
Erucamide |
(M+H)+ |
360 |
360.3237 |
+ |
Erucamide + Sodium |
(M+Na)+ |
391 |
391.2843 |
+ |
Diisooctyl phthalate (plasticiser) |
(M+H)+ |
413 |
413.2662 |
+ |
Diisooctyl phthalate (plasticiser) + Sodium |
(M+Na)+ |
425 |
|
+ |
Unidentified
contaminant (plasticiser) + Sodium |
(M+Na)+ |
429 |
429.2402 |
+ |
Diisooctyl phthalate (plasticiser) +
Potassium |
(M+K)+ |
449 |
449.3850 |
+ |
Dicyclohexyl urea (DCU) |
(2M+H)+ |
454 |
454.2928 |
+ |
Diisooctyl phthalate (plasticiser) +
Sodium + Acetonitril |
(M+Na+CH3CN)+ |
798 |
798.5878 |
+ |
Diisooctyl phthalate (plasticiser) +
Ammonia |
(2M+NH4)+ |
803 |
803.5432 |
+ |
Diisooctyl phthalate (plasticiser) +
Sodium |
(2M+Na)+ |
231, 522,
550 |
+ |
From
rubber tip of disposable syringe plunger |
|
|
297, 371,
445, 519 (+74n) |
+ |
Polysiloxanes, from air, silicone rubber |
|
|
355, 429,
503, 593, 667, 741, 815 (+74n) |
+ |
Polysiloxanes, from air, silicone rubber |
|
|
538 ,
556, 574 |
+ |
Iron carboxylate complexes: 538 = Fe3O(AcO)6, 556 =
Fe3O(AcO)6(H2O), 574 = Fe3O(AcO)6(H2O)2 |