Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
1991-7-17
pubmed:abstractText
As an example of chemical sensing based on perturbations of thermal phase transitions, we have shown that phospholipids labeled with a fluorescent dye may be used to measure the concentration of general anesthetics and other small organic molecules. The emission maximum of the hydrophobic fluorescent probe Laurdan in phospholipid bilayers shifts from a wavelength of 445 nm below the main phase transition of the lipid to 480 nm above it, with an isosbestic point at approximately 475 nm. The greatest changes in intensity at the transition occur at 440 and 500 nm, so the ratio of the intensities at these two points was used as an "order parameter". The effects of variation of the liposomal preparation method on the order parameter were explored, and it was found that in mixed lipids the parameter varied nearly linearly over the physiological temperature range. Fluorometry detected changes in the order of bilayers caused by solubilization of the anesthetic isoflurane (Forane) and of ethanol. At a defined temperature, the intensity ratio measured in the presence of anesthetic decreases in a concentration-dependent manner. Immobilizing the liposomes in a hydrogel did not perturb the response of the system. This work demonstrates the potential for using lipid phase transitions in an optical sensor for monitoring anesthetics and other small nonpolar molecules.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0003-2700
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
62
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2728-35
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Optical method for monitoring the concentration of general anesthetics and other small organic molecules. An example of phase transition sensing.
pubmed:affiliation
Center for Bioengineering, University of Washington, Seattle 98195.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't