TY - JOUR
T1 - A novel ionic liquid-in-oil microemulsion composed of biologically acceptable components
T2 - An excitation wavelength dependent fluorescence resonance energy transfer study
AU - Mandal, Sarthak
AU - Ghosh, Surajit
AU - Banerjee, Chiranjib
AU - Kuchlyan, Jagannath
AU - Banik, Debasis
AU - Sarkar, Nilmoni
PY - 2013/3/21
Y1 - 2013/3/21
N2 - In this work we have reported the formulation of a novel ionic liquid-in-oil (IL/O) microemulsion where the polar core of the ionic liquid, 1-ethyl-3-methylimidazolium n-butylsulfate ([C2mim][C 4SO4]), is stabilized by a mixture of two nontoxic nonionic surfactants, polyoxyethylene sorbitan monooleate (Tween-80) and sorbitan laurate (Span-20), in a biological oil phase of isopropyl myristate (IPM). The formation of the microemulsion droplets has been confirmed from the dynamic light scattering (DLS) and phase behavior study. To assess the dynamic heterogeneity of this tween-based IL/O microemulsion, we have performed an excitation wavelength dependent fluorescence resonance energy transfer (FRET) from coumarin 480 (C480) to rhodamine 6G (R6G). The multiple donor-acceptor (D-A) distances, ∼15, 30, and 45 Å, obtained from the rise times of the acceptor emission in the presence of a donor can be rationalized from the varying distribution of the donor, C480, in the different regions of the microemulsion system. With increasing the excitation wavelength from 375 to 408 nm, the contribution of the rise component of ∼240 ps which results the D-A distance of ∼30 Å increases significantly due to the enhanced contribution of the C480 probe molecules closer to the acceptor in the ionic liquid pool of the microemulsion.
AB - In this work we have reported the formulation of a novel ionic liquid-in-oil (IL/O) microemulsion where the polar core of the ionic liquid, 1-ethyl-3-methylimidazolium n-butylsulfate ([C2mim][C 4SO4]), is stabilized by a mixture of two nontoxic nonionic surfactants, polyoxyethylene sorbitan monooleate (Tween-80) and sorbitan laurate (Span-20), in a biological oil phase of isopropyl myristate (IPM). The formation of the microemulsion droplets has been confirmed from the dynamic light scattering (DLS) and phase behavior study. To assess the dynamic heterogeneity of this tween-based IL/O microemulsion, we have performed an excitation wavelength dependent fluorescence resonance energy transfer (FRET) from coumarin 480 (C480) to rhodamine 6G (R6G). The multiple donor-acceptor (D-A) distances, ∼15, 30, and 45 Å, obtained from the rise times of the acceptor emission in the presence of a donor can be rationalized from the varying distribution of the donor, C480, in the different regions of the microemulsion system. With increasing the excitation wavelength from 375 to 408 nm, the contribution of the rise component of ∼240 ps which results the D-A distance of ∼30 Å increases significantly due to the enhanced contribution of the C480 probe molecules closer to the acceptor in the ionic liquid pool of the microemulsion.
UR - http://www.scopus.com/inward/record.url?scp=84875438405&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84875438405&partnerID=8YFLogxK
U2 - 10.1021/jp4009515
DO - 10.1021/jp4009515
M3 - Article
C2 - 23445434
AN - SCOPUS:84875438405
SN - 1520-6106
VL - 117
SP - 3221
EP - 3231
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 11
ER -