Yes, you can run a plain silica column with water. It is called HILIC (hydrophilic interaction liquid chromatography). Water is the strong solvent. For a weak solvent, use an organic solvent such as acetone or acetonitrile. Methanol and other alcohols can be used too. You probably won't need 100% water, most compounds com off with 50% water.
You should dedicate the column to HILIC since, once wetted with water, it is very difficult at best to remove the water. Equilibration times will be longer. Any gradient should start with 1-2% water. Do not use basic modifiers- silica dissolves above pH 7 or 7.5 in polar solvents such as those used in HILIC.
See: https://www.teledyneisco.com/en-us/liquidChromatography/Chromatography%20Documents/Posters/Strategies%20for%20Flash%20Purification%20of%20Highly%20Polar%20Compounds%20Poster.pdf
https://www.teledyneisco.com/en-us/liquidChromatography/Chromatography%20Documents/Application%20Notes/RediSep%20Rf%20Gold%20Silica%20and%20Highly%20Polar%20Solvents%20App%20Note.pdf
Hi Rajendra,
is your column designated by the manufacturer as an AQ phase (=100% water)? If not, don't do it. Classic RP phases react to 100% water with a so-called phase collapse, i.e. your C18 chains then no longer protrude into the mobile phase but stick as a film to the inside of your column. In many cases, the column can not be repaired. Classic RP phases require a minimum of 2-3 % organic content in the mobile phase.
Regards
Markus
Yes, you can run a plain silica column with water. It is called HILIC (hydrophilic interaction liquid chromatography). Water is the strong solvent. For a weak solvent, use an organic solvent such as acetone or acetonitrile. Methanol and other alcohols can be used too. You probably won't need 100% water, most compounds com off with 50% water.
You should dedicate the column to HILIC since, once wetted with water, it is very difficult at best to remove the water. Equilibration times will be longer. Any gradient should start with 1-2% water. Do not use basic modifiers- silica dissolves above pH 7 or 7.5 in polar solvents such as those used in HILIC.
See: https://www.teledyneisco.com/en-us/liquidChromatography/Chromatography%20Documents/Posters/Strategies%20for%20Flash%20Purification%20of%20Highly%20Polar%20Compounds%20Poster.pdf
https://www.teledyneisco.com/en-us/liquidChromatography/Chromatography%20Documents/Application%20Notes/RediSep%20Rf%20Gold%20Silica%20and%20Highly%20Polar%20Solvents%20App%20Note.pdf
Hi Rajendra,
sorry, I didn't read your question correctly. You're talking about a silica phase and not a C18 phase. So forget what I wrote in my mail. Was my mistake. I shouldn't do several things at once. That usually goes wrong.
Jack's answer is correct.
Regards
Markus
Nope. Bare silica is hydrophilic or 'loves water' (both are polar). Thus, it will swell and die. Many specialty columns that use 100% water are endcapped with an amino moiety or some other proprietary chemical. They are labelled as AQ or perform HILIC chromatography (as labelled by the manufacturer).
Yes, you may be able to analyze tartaric acid on a silica column in the HILIC mode. (please Google the term for more). However, you have to change the mobile phase to a combination of organic solvent/water with nor more than 40% water. Please see page 7 on the attached file and go for it. This is Zic-HILIC column but it does not hurt to try on your silica column.
My experience is that bare silica doesn't swell. It does have a thin layer of adsorbed water, which is why I start any gradient at 1-2% water.
" Bare silica phases can be used for the separation of small polar compounds, such as carbohydrates, peptides, and proteins. "
http://www.chromatographyonline.com/making-hilic-work-you-column-selection
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