SH1011 column

Record: 831

Category: Specifications
Product: SH1011
Sample:

Question
Column: SH1011 + SH-G
Mobile Phase: 0.01 N H2SO4 Yes
Column temp: 60C
Flow rate: 0.6 mL/min
Injection volume: 10 uL

All the type of samples you see that cause problem: Solvents which cause increase in pressure- NMP (N-Methyl-2-pyrrolidone ), DMA (Dimethylacetamide). These solvents are the bulk of our sample, maybe 80%.
Solvents which don’t cause any pressure spike are water, DMSO, acetic acid.

Concentration of saccharides: 10% and below

Chromatogram has not changed. Pressure will slowly return to operating pressure after wash with eluent, maybe an hour or two. Pressure on column has increased about 50 psi since receiving column.

Answer
There could be a swelling effect from the organic solvent, but because of the small injection amount it is unlikely it will cause immediate alternation of the column, though in a long term it may shorten the column life when compared to analyzing aqueous samples.
Most likely, the increase of the pressure is caused by high viscosity of NMP and DMAc, and they are hard to mix with water (it is miscible, but difficult). Also, since they have hydrophilic functionality, it causes interaction with column gel and thus retained for a long time.

Since your sugar concentration is rather high (we generally analyze ~1% sugar with the column), we would recommend you to dilute your sample x10. If your target does not include organic acids and ethanol, we may recommend you to consider using NH2P series (HILIC mode) or DC series (RP mode) column which uses ACN/H2O mobile phase.

 
 
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