March 28, 2024, 07:55:42 PM
Forum Rules: Read This Before Posting


Topic: Aminoacids solubility in organic solvents  (Read 3240 times)

0 Members and 1 Guest are viewing this topic.

Offline URgEnthalpy

  • New Member
  • **
  • Posts: 7
  • Mole Snacks: +0/-0
Aminoacids solubility in organic solvents
« on: August 10, 2018, 07:06:08 AM »
I can't find literally any info about solubility of aminoacids and similar compounds (creatine, taurine) in organic solvents.
I am a little bit confused if the best solubility would be in their isoelectric point, or protonated/ deprotonated form. Would be direct pouring on the powders CH2Cl2 better, or making solution in the first place and adjusting right pH is a better solution?
« Last Edit: August 10, 2018, 09:50:13 AM by sjb »

Offline Babcock_Hall

  • Chemist
  • Sr. Member
  • *
  • Posts: 5592
  • Mole Snacks: +319/-22
Re: Aminoacids solubility in organic solvents
« Reply #1 on: August 10, 2018, 08:51:35 AM »
I have often worked with amino acids, but I have not seen information on the solubility in in organic solvents.  I suspect that you are correct about the isoelectric point.  Obviously if working with them as BOC-derivatives is a possibility, that might be somewhat easier.  However, my experience is that even BOC-derivatives will partition from ethyl acetate into water if the carboxylic acid group is deprotonated to form a carboxylate.  Were you able to calculate the pI values of the compounds of interest to you?

Offline wildfyr

  • Global Moderator
  • Sr. Member
  • ***
  • Posts: 1771
  • Mole Snacks: +203/-10
Re: Aminoacids solubility in organic solvents
« Reply #2 on: August 10, 2018, 11:20:54 AM »
I bet they are all soluble in methanol, DMF and DMSO at all pHs.

Offline Babcock_Hall

  • Chemist
  • Sr. Member
  • *
  • Posts: 5592
  • Mole Snacks: +319/-22
Re: Aminoacids solubility in organic solvents
« Reply #3 on: August 10, 2018, 11:37:00 AM »
https://www.tandfonline.com/doi/pdf/10.1080/00021369.1966.10858601
Hayashi K, et al., Agr. Biol. Chem., Vol. 30, No.4, pp. 378-384, 1966
See Table I for data on methanol and ethanol.

Offline wildfyr

  • Global Moderator
  • Sr. Member
  • ***
  • Posts: 1771
  • Mole Snacks: +203/-10
Re: Aminoacids solubility in organic solvents
« Reply #4 on: August 10, 2018, 11:40:29 AM »
Dang, I was wrong. This data says to me that there isn't a blanket statement one can make about amino acid solubility, it's a case by case basis. At their isoelectric point they will indeed be most soluble in organics like DCM.

Offline Babcock_Hall

  • Chemist
  • Sr. Member
  • *
  • Posts: 5592
  • Mole Snacks: +319/-22
Re: Aminoacids solubility in organic solvents
« Reply #5 on: August 10, 2018, 11:45:23 AM »
One question that has long occurred to me is what is the tautomeric equilibrium for an amino acid in an organic solvent.  I would think that it would be very different from water, but I have never seen data that address this question.

Sponsored Links