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Ionization effect of microM addition of Sodium Acetate
Monosaccharide - Glucose retention in the ANP mode
Method Conditions
| Column |
Cogent Diamond Hydride™, 4µm, 100A |
| Catalog No. |
70000-15P-2 |
| Dimensions |
2.1 x 150 mm |
| Solvents |
In Chromatogram A:
A: 80% DI water/20% methanol/0.1% formic acid
B: 100% acetonitrile/0.2% acetic acid
In Chromatogram B:
A: 80% DI water/20% methanol/0.1% formic acid/
100 microM sodium acetate
B: 100% acetonitrile/0.2% acetic acid
ATTENTION: Sodium Acetate concentration is in microM. Higher
concentration is harmful for MS. |
| Gradient |
| Time (min) | %B | Time (min) | %B |
| 0.0 | 100.0 | 7.0 | 50.0 |
| 1.0 | 100.0 | 8.0 | 100.0 |
| 4.0 | 50.0 | | |
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| Post time |
5 min. |
| Flow rate |
0.600 mL/min. |
| Injection |
1µL |
| Samples |
Glucose 10 ppm, m/z 203.0526 (M+Na)+ |
| Detection |
ESI – pos - Agilent 6210 MSD TOF mass spectrometer |
Discussion
Glucose, a simple monosaccharide, was analyzed by LC-MS and the peak is very symmetrical and easy
to integrate. This application note illustrates the importance of addition of microM amount of
sodium to the mobile phase when sugars are analyzed. Sodium adducts of sugars produce much better
signal in LC-MS analysis (at least 10 times higher signal for the same sample) – see chromatograms
A and B. When glass bottles are used there is enough sodium leaching from the glass that it is
possible to find very strong signals for the sodium adduct.
Notes: This method may be useful for determination of monosaccharides in blood. Samples used are
un-derivatized with detection possible with mass spectrometry. Biological sample preparation is
simple, generally focused on the removal of proteins and other high molecular weight components of
plasma, urine and saliva.
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