|
Repeating units observed in LC-MS background |
|||
|
Ion Mass
(Da) |
Accurate
Mass (Da) |
Mode |
Compound |
|
+14n |
14.0157 |
+ |
[CH2], Alkane chains |
|
+15n |
15.9949 |
+ |
O,
Oxidation |
|
+18n |
18.0106 |
+/- |
Water
clusters |
|
+28n |
28.0313 |
+ |
[C2H4],
natural alkene chains |
|
+32n |
32.0262 |
+ |
Methanol
clusters |
|
+41n |
41.0266 |
+ |
Acetonitrile clusters |
|
+42n |
42.0470 |
+ |
[C3H6], propyl repeating chains |
|
+44n |
44.0262 |
+ |
Polyethylene
glycol related (-CH2CH2O-)n, PEG |
|
+50n |
49.9968 |
+ |
[CF2], perfluoro compounds |
|
+53n |
53.0032 |
+ |
Ammonium
chloride adducts (NH4Cl) |
|
+56n |
56.0626 |
+ |
[C4H8],
Butyl repeating units |
|
+58n |
58.0419 |
+ |
Polypropylene
glycol related (CH2CH2CH2O)n |
|
+58n |
57.9586 |
+ |
NaCl adducts (distinguishable from PPG by Cl
Isotope pattern) |
|
+63n |
63.032 |
+ |
Ammonium formate adducts (HCOONH4) |
|
+68n |
67.9874 |
+/- |
Sodium formate adducts (HCOO-Na) |
|
+72n |
72.0395 |
+ |
Replacement
of –OH by –OSi(CH3)3 |
|
+74n |
74.0188 |
+/- |
Polysiloxanes (Si(CH3)2O) |
|
+74n |
73.9326 |
+ |
KCl adducts (distinguishable by Cl isotope
pattern) |
|
+77n |
77.0477 |
+ |
Ammonium
acetate salts (CH3COONH4) |
|
+78n |
78.0139 |
+ |
DMSO
adducts ((CH3)2SO) |
|
+82n |
82.0031 |
+/- |
Sodium acetate
adducts (CH3COONa) |
|
+114n |
113.9929 |
- |
TFA (trifluoroacetic acid) adducts (CF3COOH) |
|
+122n |
121.9383 |
- |
Sodium perchlorate adducts (NaClO4) |
|
+136n |
135.9748 |
+/- |
Sodium
TFA (trifluoroacetic acid) adducts (CF3COONa) |
|
+162n |
162.0528 |
+ |
Polysaccharides
(C6H10O5) |
|
+226n |
226.1681 |
+ |
[C12H22N2O2] cyclic oligomers from polyamide |
|
+288n |
288.1371 |
- |
SDS
(sodium dodecylsulfate) adducts (CH3(CH2)11OSO3Na) |