Linked Life Data

11458340

Source:http://linkedlifedata.com/resource/pubmed/id/11458340

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2001-7-17
pubmed:abstractText
It has been shown that significant pore induction (electroporation) occurs in human epidermal membrane (HEM) during iontophoresis even at moderate applied voltages (1-10 V). Recent efforts in our laboratory have been aimed at quantifying HEM electroporation by examining the proportionality between flux enhancement due to electroporation and electrical conductance changes during iontophoresis. The specific purpose of the present study was to test the hypothesis that by matching the background electrolyte ion sizes with the permeant ion sizes, the flux enhancement due to electroporation can be quantified by the change in HEM electrical conductance. In this study, radiolabeled tetraethylammonium (TEA(+)), methylammonium (MA(+)), and mannitol were the permeants. Potassium chloride (KCl), tetraethylammonium bromide (TEAB), tetraethylammonium pivalate (TEAP), and sodium fluoride (NaF) were the background electrolytes. Iontophoresis experiments were carried out over an applied voltage range of 1 to 3 V. The experimental flux enhancement results were compared with the theoretical predictions from the Nernst-Planck model after corrections were made: (a) for HEM pore induction during iontophoresis based on electrical conductance changes and (b) for electroosmosis employing mannitol as the neutral probe permeant. In experiments where the ion sizes of the background electrolyte and permeant were closely matched (e.g., TEA(+) as the permeant and TEAP as the background electrolyte), there was excellent agreement between experimental results and theoretical predictions of the modified Nernst-Planck model, with only modest data scatter. When the electrolyte and permeant sizes were quite different (e.g., TEA(+)/KCl and MA(+)/TEAP), the experimental flux data were inconsistent with model predictions and there were large variations in the experimental results. The results of the present study illustrate that permeant flux enhancement can be predicted by the modified Nernst-Planck model even during moderate voltage iontophoresis when electroporation is operative.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0022-3549
pubmed:author
pubmed:issnType
Print
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
932-42
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Quantification of pore induction in human epidermal membrane during iontophoresis: the importance of background electrolyte selection.
pubmed:affiliation
Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, 30 S 2000 E Rm. 213, Salt Lake City, Utah 84112, USA. h.zhu@m.cc.utah.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.