Dear Osama,

Spermine reacts with PBS to form spermine phosphat which is insoluble in water (pH 5). In order to dissolve it, more HCl should be added and the solution should be acidic. I expect if you add more 6N HCl until pH 3 the cloudy solution will turn transparentsince most of the spermine phosphate is converted to spermine HCl, which is soluble.

For more information on the solubility of spermine, please use the following link:

'http://www.scbt.com/datasheet-296413.html

Hoping this will be helpful,

Rafik

Thank you so much Dr.Rafik for your answer.

I have not tried to add more HCL to dissolve it because I want the pH to be at 5.