zwitter ion solubility

[TalinAagam]

are zwitter ions soluble in water? I was always thought in class that zwitter ions are solids in the intestines.

 

[PinknGreenMD]

they are neutral

 

[CaffeineZombie]

Similar to ionic salts, a zwitterion in the absence of a polar solvent like water, is in the solid form. NaCl is one example. But the moment you dump NaCl into a liquid, it dissociates for the more favorable attraction with water.

http://www.chemguide.co.uk/organicprops/aminoacids/background.html

"Amino acids are generally soluble in water and insoluble in non-polar organic solvents such as hydrocarbons.

This again reflects the presence of the zwitterions. In water, the ionic attractions between the ions in the solid amino acid are replaced by strong attractions between polar water molecules and the zwitterions. This is much the same as any other ionic substance dissolving in water.

The extent of the solubility in water varies depending on the size and nature of the "R" group."

 

[TalinAagam]

Similar to ionic salts, a zwitterion in the absence of a polar solvent like water, is in the solid form. NaCl is one example. But the moment you dump NaCl into a liquid, it dissociates for the more favorable attraction with water.

http://www.chemguide.co.uk/organicprops/aminoacids/background.html

"Amino acids are generally soluble in water and insoluble in non-polar organic solvents such as hydrocarbons.

This again reflects the presence of the zwitterions. In water, the ionic attractions between the ions in the solid amino acid are replaced by strong attractions between polar water molecules and the zwitterions. This is much the same as any other ionic substance dissolving in water.

The extent of the solubility in water varies depending on the size and nature of the "R" group."

Thanks,

Its weird because I remember my teacher kept telling us that amino acids are solid in the intestine at neutural pH, thats why they need special transporters to get into the body.

 

[CaffeineZombie]

Thanks,

Its weird because I remember my teacher kept telling us that amino acids are solid in the intestine at neutural pH, thats why they need special transporters to get into the body.

Hmm. She could have instead meant to say that because zwitterions are polar species, they need transporter proteins to transport across the non-polar membranes. I suppose you could consider this membrane to be a solid network of lipids bound together to form a non-permeable membrane.

 

[gettheleadout]

Thanks,

Its weird because I remember my teacher kept telling us that amino acids are solid in the intestine at neutural pH, thats why they need special transporters to get into the body.

Yeah, that doesn't make any sense. AA's are definitely going to be soluble in chyme and then in the intestinal juice mix of the small intestine.