T. Hano et al., SEPARATION OF DIPEPTIDES AND TRIPEPTIDES WITH SOLVENT-EXTRACTION AND AN EMULSION LIQUID MEMBRANE, Journal of chemical technology and biotechnology, 62(1), 1995, pp. 60-63
The extraction equilibria of various di- and tripeptides with di-2-eth
ylhexylphosphoric acid (D2EHPA) were studied at low pH values. The com
plex extracted to organic phase consisted of one molecule of peptide a
nd two molecules of D2EHPA dimer. The extraction constants of the pept
ides correlated well with the distribution coefficients of peptides be
tween 1-octanol and water, which is a measure of hydrophobicity. The p
ermeation rates of peptides through an emulsion liquid membrane were e
xamined by using D2EHPA as a carrier, Span 80 as an emulsifier and ker
osene as a diluent. The rates varied considerably with peptide type, d
epending upon the hydrophobicity.