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urgent help needed-80% sucrose - (Feb/21/2005 )

I can not dissolve 80% sucrose
what can I do?
can you order it from somewhere?


Wow. It's been a long time since I prepared something like this. I believe the only way to dissolve it is by heating the solution while stirring... and with patience. The solubility of sucrose at RT is 1M, and you want more than twice that. It will look like a candy in the end.
Hope that helps!


heat to what temp? I think at high tempretures it polymerizes. I'm heating to 35 degrees for over 24 hours now and it is still not dissolving. sad.gif


I dissolved sucrose to 84%. Don't know what teperature I heated it up to. I just put it on the striring/heating plate at pretty low heating and added sucrose a few mg at the time... it took me a whole day but I got enough sucrose to do all my gradients afterwards.



Heat water say at about 60C (avoid high temperature as it may charr the compound into caramel) and add sucrose in small increments. When further additions fail to go into the solution, you have reached the saturation point. Filter the solution after cooling it (somemore might crystallize out) and this will be 100% solution. Dilute appropriately.

The solubility of sucrose at high concentration depends on the ionic strength of the solvent employed. What might be quick with distilled water might be tedious with a buffer. If you are using a buffer, then try with a that of lower strength. If you had used water, then use good quality distilled and deionised water.

If you still fail, then ask some nice lady how to make a sugar syrup for a candy bar.

good luck