Multivariate data analysis for enhanced interpretation of electrochemical impedance spectra of gramicidin-ion interactions in phospholipid monolayers.
This article describes a multifrequency electrochemical impedance study of phospholipid monolayers on a mercury drop electrode in solutions containing electrolytes and gramicidin derivatives: gramicidin A (gA), gramicidin-BOC (g-BOC), and desformylgramicidin (g-des). The impedance spectra have been studied individually (univariate approach) and also transformed using a multivariate data reduction method (multivariate approach). It was shown that the two approaches are complementary. Thus the formation of K+-conducting channels is observed in gA only, and these channels can be distinguished from an interaction of all gramicidin derivatives with Mg2+. An unknown peptide interaction in the monolayer was observed on a slow time scale.
Lindholm-Sethson
Britta
B
Department of Chemistry and Centre for Biomedical Engineering and Physics, Umeå University, SE-901 87 Umea, Sweden.
Geladi
Paul
P
Koeppe
Roger E
RE
Jonsson
Oskar
O
Nilsson
David
D
Nelson
Andrew
A
D004563:Electrochemistry; D004566:Electrodes; D004573:Electrolytes; D006096:Gramicidin / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D008567:Membranes, Artificial; D008628:Mercury / Q000737:chemistry; D015999:Multivariate Analysis; D010743:Phospholipids / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry; D013499:Surface Properties
D004573:Electrolytes; D007477:Ions; D008567:Membranes, Artificial; D010743:Phospholipids; D012996:Solutions; D006096:Gramicidin; D008628:Mercury