Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2003-2-12
pubmed:abstractText
The separation of six related opiate alkaloids (morphine, thebaine, 10-hydroxythebaine, codeine, oripavine and laudanine) was studied using sulfated-cyclodextrin (s-CD) as a cation-exchange pseudo-stationary phase. Cation-exchange interactions between the cationic analytes and the anionic s-CD (7-11 mol of sulfate groups per mole CD) were found to bethe predominant mechanism, allowing the separations to be performed at low pH where the opiates are protonated and exhibit very similar mobilities. The concentrations of the s-CD and the competing ion (Na+ or Mg2+) in the electrolyte were used to govern the extent of the ion-exchange interactions. Interactions with the sulfated-cyclodextrin differed for each analyte, with oripavine exhibiting the strongest interaction and 10-thebaine and laudanine showing the weakest interactions. Despite the very similar structures of the analytes, these differences resulted in significant changes in separation selectivity. The separation was modelled using a migration equation derived from first principles and based on ion-exchange interactions between the s-CD and the opiates. Constants within the model were obtained by non-linear regression using a small subset of experimentally determined migration times. These constants related to the ion-exchange affinities of the s-CD for the various opiates. When the model was used to predict migration times under other experimental conditions, a very good correlation was obtained between observed and predicted mobilities (r2=0.996). Optimisation of the system was performed using the normalised resolution product and minimum resolution criteria and this process provided two optimised separations, each exhibiting a different separation selectivity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0021-9673
pubmed:author
pubmed:issnType
Print
pubmed:day
24
pubmed:volume
985
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
493-501
pubmed:dateRevised
2009-1-15
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Separation of opiate alkaloids by electrokinetic chromatography with sulfated-cyclodextrin as a pseudo-stationary phase.
pubmed:affiliation
Australian Centre for Research on Separation Science. School of Chemistry, University of Tasmania, GPO Box 252-75, Hobart, Tasmania 7001, Australia.
pubmed:publicationType
Journal Article