TY - JOUR
T1 - Ionic liquids affect the adsorption of liposomes onto cationic polyelectrolyte coated silica evidenced by quartz crystal microbalance
AU - Duša, Filip
AU - Ruokonen, Suvi Katriina
AU - Petrovaj, Ján
AU - Viitala, Tapani
AU - Wiedmer, Susanne K.
N1 - Funding Information:
Financial support from the Academy of Finland , project numbers 266342 (SKW), 276075 (SKW), 263861 (TV), and 137053 (TV), 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.
Publisher Copyright:
© 2015 Elsevier B.V..
PY - 2015/12/1
Y1 - 2015/12/1
N2 - The worldwide use of ionic liquids (ILs) is steadily increasing, and even though they are often referred to as "green solvents" they have been reported to be toxic, especially toward aquatic organisms. In this work, we thoroughly study two phosphonium ILs; octyltributylphosphonium chloride ([P8444]Cl) and tributyl(tetradecyl)phosphonium chloride ([P14444]Cl). Firstly, the critical micelle concentrations (CMCs) of the ILs were determined with fluorescence spectroscopy and the optical pendant drop method in order to gain an understanding of the aggregation behavior of the ILs. Secondly, a biomimicking system of negatively charged unilamellar liposomes was used in order to study the effect of the ILs on biomembranes. Changes in the mechanical properties of adsorbed liposomes were determined by quartz crystal microbalance (QCM) measurements with silica coated quartz crystal sensors featuring a polycation layer. The results confirmed that both ILs were able to incorporate and alter the biomembrane structure. The membrane disrupting effect was emphasized with an increasing concentration and alkyl chain length of the ILs. In the extreme case, the phospholipid membrane integrity was completely compromised.
AB - The worldwide use of ionic liquids (ILs) is steadily increasing, and even though they are often referred to as "green solvents" they have been reported to be toxic, especially toward aquatic organisms. In this work, we thoroughly study two phosphonium ILs; octyltributylphosphonium chloride ([P8444]Cl) and tributyl(tetradecyl)phosphonium chloride ([P14444]Cl). Firstly, the critical micelle concentrations (CMCs) of the ILs were determined with fluorescence spectroscopy and the optical pendant drop method in order to gain an understanding of the aggregation behavior of the ILs. Secondly, a biomimicking system of negatively charged unilamellar liposomes was used in order to study the effect of the ILs on biomembranes. Changes in the mechanical properties of adsorbed liposomes were determined by quartz crystal microbalance (QCM) measurements with silica coated quartz crystal sensors featuring a polycation layer. The results confirmed that both ILs were able to incorporate and alter the biomembrane structure. The membrane disrupting effect was emphasized with an increasing concentration and alkyl chain length of the ILs. In the extreme case, the phospholipid membrane integrity was completely compromised.
KW - Critical micelle concentration
KW - Ionic liquids
KW - Liposomes
KW - Polybrene
KW - Quartz crystal microbalance
KW - Toxicity
UR - http://www.scopus.com/inward/record.url?scp=84943616692&partnerID=8YFLogxK
U2 - 10.1016/j.colsurfb.2015.09.059
DO - 10.1016/j.colsurfb.2015.09.059
M3 - Article
C2 - 26454056
AN - SCOPUS:84943616692
SN - 0927-7765
VL - 136
SP - 496
EP - 505
JO - Colloids and Surfaces B: Biointerfaces
JF - Colloids and Surfaces B: Biointerfaces
ER -