TY - JOUR
T1 - Effect of ionic liquids on the interaction between liposomes and common wastewater pollutants investigated by capillary electrophoresis
AU - Ruokonen, Suvi Katriina
AU - Duša, Filip
AU - Lokajová, Jana
AU - Kilpeläinen, Ilkka
AU - King, Alistair W.T.
AU - Wiedmer, Susanne K.
N1 - Funding Information:
Financial support from the Academy of Finland , project numbers 266342 (SKW) and 276075 (SKW), and from Magnus Ehrnrooth Foundation (SKW) is greatly acknowledged. Jeff Dyck and Al Robertson from Cytec Industries are gratefully acknowledged for providing their off-the-shelf phosphonium chloride salts. All studied compounds were a kind gift from professor Michael Lämmerhofer at the University of Tübingen, Institute of Pharmaceutical Sciences, Germany.
Publisher Copyright:
© 2015 Elsevier B.V.
PY - 2015/7/31
Y1 - 2015/7/31
N2 - The effect of three phosphonium and imidazolium ionic liquids (ILs) on the interaction between liposomes and common pharmaceuticals found in wastewaters was studied. The liposomes comprised zwitterionic phosphatidyl choline and negatively charged phosphatidyl glycerol. A set of common cationic, anionic, and neutral compounds with varying chemical composition and unique structures were included in the study. The electrophoretic mobilities of the analytes were determined using conventional capillary electrophoresis (CE), using CE under reversed electroosmotic flow mobility conditions, and in the presence of ILs in the background electrolyte (BGE) solution by electrokinetic chromatography (EKC). In order to evaluate the impact of ILs on the interaction between the compounds and the liposomes, EKC was performed with liposome dispersions, with and without ILs. The retention factors of the compounds were calculated using BGEs including liposome dispersions with and without ILs. Two phosphonium based ILs, namely tributyl(tetradecyl)phosphonium chloride ([P14444]Cl) and octyltributylphosphonium chloride ([P8444]Cl), were chosen due to their long alkyl chains and their low aggregation concentrations. Another IL, i.e. 1-ethyl-3-methylimidazolium acetate ([emim][OAc]), was chosen based on our previous study, which suggests that it has a minimal or even nonexistent effect on liposomes at the used concentrations.The results indicate that the studied ILs have an effect on the interactions between wastewater compounds and liposomes, but the effect is highly dependent on the concentration of the IL and on the IL alkyl chain lengths. Most of the ILs hindered the interactions between the liposomes and the compounds, indicating strong interaction between ILs and liposomes. In addition, the nature of the studied compounds themselves affected the interactions.
AB - The effect of three phosphonium and imidazolium ionic liquids (ILs) on the interaction between liposomes and common pharmaceuticals found in wastewaters was studied. The liposomes comprised zwitterionic phosphatidyl choline and negatively charged phosphatidyl glycerol. A set of common cationic, anionic, and neutral compounds with varying chemical composition and unique structures were included in the study. The electrophoretic mobilities of the analytes were determined using conventional capillary electrophoresis (CE), using CE under reversed electroosmotic flow mobility conditions, and in the presence of ILs in the background electrolyte (BGE) solution by electrokinetic chromatography (EKC). In order to evaluate the impact of ILs on the interaction between the compounds and the liposomes, EKC was performed with liposome dispersions, with and without ILs. The retention factors of the compounds were calculated using BGEs including liposome dispersions with and without ILs. Two phosphonium based ILs, namely tributyl(tetradecyl)phosphonium chloride ([P14444]Cl) and octyltributylphosphonium chloride ([P8444]Cl), were chosen due to their long alkyl chains and their low aggregation concentrations. Another IL, i.e. 1-ethyl-3-methylimidazolium acetate ([emim][OAc]), was chosen based on our previous study, which suggests that it has a minimal or even nonexistent effect on liposomes at the used concentrations.The results indicate that the studied ILs have an effect on the interactions between wastewater compounds and liposomes, but the effect is highly dependent on the concentration of the IL and on the IL alkyl chain lengths. Most of the ILs hindered the interactions between the liposomes and the compounds, indicating strong interaction between ILs and liposomes. In addition, the nature of the studied compounds themselves affected the interactions.
KW - Capillary electromigration techniques
KW - Ionic liquids
KW - Liposomes
KW - Wastewater compounds
UR - http://www.scopus.com/inward/record.url?scp=84937513064&partnerID=8YFLogxK
U2 - 10.1016/j.chroma.2015.05.064
DO - 10.1016/j.chroma.2015.05.064
M3 - Article
C2 - 26072299
AN - SCOPUS:84937513064
SN - 0021-9673
VL - 1405
SP - 178
EP - 187
JO - Journal of Chromatography A
JF - Journal of Chromatography A
ER -