TY - JOUR
T1 - Formation and potential application of micelles composed of biocompatible N-lauroyl-amino acid ionic liquids surfactant
AU - Moshikur, Rahman Md
AU - Ali, Md Korban
AU - Wakabayashi, Rie
AU - Moniruzzaman, Muhammad
AU - Goto, Masahiro
N1 - Funding Information:
This study was supported by the Japan Society for the Promotion of Science (JSPS) (KAKENHI No. JP19H05518 ). The authors thank Hiroki Obayashi for help with TEM and Dr. M. Watanabe for facility support for NMR, TGA and DSC. We also thank Renee Mosi, PhD, from Edanz Group ( https://en-author-services.edanzgroup.com/ ) for editing a draft of this manuscript.
Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2020/12/15
Y1 - 2020/12/15
N2 - Surface-active ionic liquid (SAIL) surfactants have attracted attention as promising alternatives to conventional surfactants because of their tailor-made and tunable properties. SAILs also address the limitations associated with conventional surfactants including toxicity and formation of unstable micelles. Here, we investigated the aggregation behavior of three biocompatible choline N-lauroyl-amino acid (NLAA)-based ILs with different amino acid side chains in aqueous solutions. The micellar behaviors of NLAA-ILs were investigated using surface tensiometry, conductometry, dynamic light scattering (DLS) and transmission electron microscopy (TEM). The critical micellar concentration (CMC) of the NLAA-ILs was found to be 2 to 4-fold lower compared with the conventional surfactant sodium dodecyl sulfate (SDS). The thermodynamic behavior confirmed that the micelle formation of NLAA-ILs was stable, spontaneous and entropy driven at room temperature. DLS and TEM studies revealed that the size and shape of the micelles depended on the presence of an N‑hydrogen group in the head group of the anion. Choline N-lauroyl glycinate ([Cho][NLG]) and dicholine N-lauroyl aspartate ([Cho]2[NLA]) were predominantly produced as unilamellar vesicles in water whereas choline N-lauroyl sarcosinate ([Cho][NLS]) formed small spherical micelles. Importantly, SAIL [Cho][NLG] showed lower toxicity toward mammalian cells compared with the analogous ILs or the conventional surfactant SDS and similar toxicity to the conventional surfactant Tween 80. SAIL [Cho][NLG] was more efficient at forming hydrophobic ion pairs with the macromolecular drug heparin compared with SAIL [Cho][NLS]. These results clearly suggest that the biocompatible NLAA-ILs represent promising potential substitutes for conventional surfactants in various biomedical applications.
AB - Surface-active ionic liquid (SAIL) surfactants have attracted attention as promising alternatives to conventional surfactants because of their tailor-made and tunable properties. SAILs also address the limitations associated with conventional surfactants including toxicity and formation of unstable micelles. Here, we investigated the aggregation behavior of three biocompatible choline N-lauroyl-amino acid (NLAA)-based ILs with different amino acid side chains in aqueous solutions. The micellar behaviors of NLAA-ILs were investigated using surface tensiometry, conductometry, dynamic light scattering (DLS) and transmission electron microscopy (TEM). The critical micellar concentration (CMC) of the NLAA-ILs was found to be 2 to 4-fold lower compared with the conventional surfactant sodium dodecyl sulfate (SDS). The thermodynamic behavior confirmed that the micelle formation of NLAA-ILs was stable, spontaneous and entropy driven at room temperature. DLS and TEM studies revealed that the size and shape of the micelles depended on the presence of an N‑hydrogen group in the head group of the anion. Choline N-lauroyl glycinate ([Cho][NLG]) and dicholine N-lauroyl aspartate ([Cho]2[NLA]) were predominantly produced as unilamellar vesicles in water whereas choline N-lauroyl sarcosinate ([Cho][NLS]) formed small spherical micelles. Importantly, SAIL [Cho][NLG] showed lower toxicity toward mammalian cells compared with the analogous ILs or the conventional surfactant SDS and similar toxicity to the conventional surfactant Tween 80. SAIL [Cho][NLG] was more efficient at forming hydrophobic ion pairs with the macromolecular drug heparin compared with SAIL [Cho][NLS]. These results clearly suggest that the biocompatible NLAA-ILs represent promising potential substitutes for conventional surfactants in various biomedical applications.
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U2 - 10.1016/j.molliq.2020.114424
DO - 10.1016/j.molliq.2020.114424
M3 - Article
AN - SCOPUS:85092062921
SN - 0167-7322
VL - 320
JO - Journal of Molecular Liquids
JF - Journal of Molecular Liquids
M1 - 114424
ER -