We have to determine particle contamination, but cannot get an otherwise clear solution. Tried deionized and tap water, alternatively DMSO - room temperature and boiling for 1 % gum. Want to avoid too harsh acids or alkali and obtain a simple procedure for sample treatment. Next dissolution trial in 1 % soda solution containing H2O2.
Titus, are you working with "pure" E410 (aka carob gum, or carob bean gum - a highly milled powder) or some derivative of juice from fresh beans? If you are working with E410 or the like I wouldn't ever expect you to get a good dissolve because it forms a colloidal solution made of polysaccharides when exposed to water. It can be dispersed with water but water isn't a solvent for it. You might try looking at this article for some ideas - http://www.mdpi.com/1420-3049/18/1/1270/pdf
Could you try rather week CH3COOH /5%/ or NH4OH 5% water solution at ambient temperature? If it does not work, incease the temperature to some 50 oC, or use supersound treatment of the gum in the above mentioned chemicals....
Colloidal partices do not sediment easily and form homogenous colloidal solution. Regards,
R.S.
Thanks for the answers. I was a bit confused about all more general descriptions stating that for 1 % after heating one should get a clear solution opposite to our observations.
Samples are supposed to be pure ground Locust bean gum, where the gum itself is said to be the same.
There seem to be a relation between degree of contamination and resistance to dissolve, i.e. more of the white stuff remains visibly dispersed when content of dark particles is higher.
Unfortunately, we have no LiCl available to test for solubility in LiCl/DMSO.
'Solubility' after intense sonication for 10 minutes is considerably better in 5 % NH4OH than in 5 % AcOH. For both, however, white colloidal matter is obvious. One sample turns black for which 'dissolution' is most difficult.
Titus,
Is it possible, that both white and black dispersed particles in the solution might be some chemical or mechanical impurities maybe of low polarity in nature, or condensed one, and from this reason insoluble. Could you make some preliminary "extractions"? :
a/ disperse the resin in a low polarity solvent or non polar one, e.g. in THF, acetone or n-hexane /non polar/, filter of your preparation, wash with the same solvent and let it evaporate.
b/ in the case that the impurities might be polar /regardless white or dark - this pays also for non polar extraction /item a/ /, disperse the resin in unhydrous ethanol or methanol, filter of the purified material, wash it, and let solvent evaporate at room temperature.
Repeat your experiments with "purified" resin, and combine them with supersound sonification.
Note: test also the resine solubility in 5% water solution of primary or secondary amine /CH3NH2 or /CH3/2NH / with and without application of supersound. Due to higher basicity of such a solvent try to dissove your sample in the absence of air oxygen, N2 atmosphere would be sufficient.
Best regards,
R.S.
Dear Rastislav,
thank you very much for your support and triggering ideas. The actual case was very practical, far from academical. Nevertheless, at least in complicate cases, thorough understanding is mandatory.
At the end we had to give up because we had to find a quick fix without studying the topic in ex-tense.
It seems under conditions evaluated most of the white powder, which should be locust bean gum, remained insoluble. By drastic conditions it may have been solubilized, however, would this not alter the contaminating particles too?
So in essence solution to the problem of quantifying contamination maybe possible, but would require further intense study. By the way it seems that one sample contains lot of small dark particles, the others fewer but larger particles.
Thank all who contributed to this discussion.
Please help me, I am also straggling with the same problem, dissolving Locust Bean Gum. Titus Sobisch, which method I should follow to dissolve Locust Bean Gum. Give me a suggestion to this query.
Respected Titus Sobisch, Do you tried with 1% Sodium solution containing H2O2, which was mentioned above.
It is not different than the other attempts. Can only speak about the 3 samples we had.
This might sound primitive but I microwaved a 1% solution less than 1 minute and turn off every time it boiled for several times
Then just leave it on boiling water for about half an hour. Being in the microwave helps with heating and mixing the solution. But I'm.not sure if it will do.major damage to the structures of the molecules.
- Badges
- Science topic
- Similar topics
- Biological Science
- Biochemistry
- Biomolecules
- Peptides