Linked Life Data

9764514

Source:http://linkedlifedata.com/resource/pubmed/id/9764514

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1998-10-23
pubmed:abstractText
A method was developed for determining pH differences across cell membranes using a methylammonium-selective membrane electrode, based on monitoring of the pH gradient-induced uptake of methylammonium in situ. The methylammonium electrode was constructed using calix[6]arene-hexaacetic acid hexaethyl ester as a neutral carrier and bis(2-ethylhexyl) sebacate as a membrane solvent in a poly(vinyl chloride) membrane matrix. This electrode exhibited a near-Nernstian response to methylammonium in the concentration range 2 x 10(-5)-1 x 10(-2) M with a slope of 58 mV per concentration decade in a buffer solution of 150 mM choline chloride-10 mM TRIS-HCl (pH 7.5). The limit of detection was 5 x 10(-6) M. In experiments using liposomes, the uptake of methylammonium into liposomes occurred effectively when the pH of the outside suspension medium was alkaline, and the determination of changes in methylammonium concentrations in the outer medium was quantitatively related to changes in the pH differences across the liposomal membrane. The transmembrane pH differences in Escherichia coli cells were also determined by this method.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0003-2654
pubmed:author
pubmed:issnType
Print
pubmed:volume
123
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1369-72
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Determination of the pH difference across a cell membrane using a methylammonium-selective membrane electrode.
pubmed:affiliation
Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Japan. katsu@pheasant.pharm.okayama-u.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't