Linked Life Data

1309661

Source:http://linkedlifedata.com/resource/pubmed/id/1309661

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1992-2-20
pubmed:abstractText
Consideration of the interfacial protonation equilibria of membrane-associated amphiphiles indicates that the partition coefficients of the protonated and unprotonated species will differ considerably. The partition coefficients of the charged and uncharged forms of spin-labelled myristic acid in dimyristoylphosphatidylcholine bilayer dispersions have been measured by EPR spectroscopy and found to be approximately 140-fold higher for the protonated acid than for the dissociated salt form. This ratio of partition coefficients is found to be in good agreement with that predicted from the interfacial shift in pKa of the fatty acid on its partitioning into the membrane. The latter was determined from the changes in the EPR spectra of the membrane-associated fatty acid with pH and was found to be +2.1 pH units. The interfacial shifts in pKa for a series of spin-labelled analogues of tertiary amine local anaesthetics have been determined from the pH dependence of the partition coefficients in dimyristoylphosphatidylcholine bilayer dispersions and are found mostly to be in the range of approx. -1.0 to -1.5 pH units, corresponding to a 10- to 30-fold higher partition coefficient of the uncharged base compared with that of the charged ammonium form.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
1103
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
62-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Interfacial ionization and partitioning of membrane-bound local anesthetics.
pubmed:affiliation
Max-Planck-Institut für biophysikalische Chemie, Abteilung Spektroskopie, Göttingen, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't