under the supervision of Prof. M. R. Islam Dr. Sujit Kumar Ghosh Department of Chemistry Assam University Silchar-788011, by Hirak Chatterjee
Nov 03, 2014
under the supervision of
Prof. M. R. Islam
Dr. Sujit Kumar Ghosh
Department of Chemistry Assam University Silchar-788011, Assam INDIA
by
Hirak Chatterjee
• Molecules accumulate at the interface between air and solvent.
• Reduces surface tension of the liquid.
• Shape of aggregates changes according to surfactant conc. of
the system.
• Based on the electrostatic interaction between dye & surfactant molecules.
• The following equilibrium occurs: L (aqueous phase, CL) ↔ SLN
(surfactant phase, CS) in L-S solution
• Optical detection method.
• Dye adsorption occur at miceller core.
• Dyes show different adsorption & emission spectra based on surfactant
concentration.
• Applicable for premiceller concentration of surfactants also.
• Premiceller self assembly of dye-surfactant systems can be elucidated.
Dye molecules
Surfactant molecules
Solvent molecules
• Cetylammonium bromide (CTAB)
• CMC=8×10-3 mol/dm3.
N Me3 BrH3C
• Flourescein isothiocyanate (FITC) Two sugar analogues of FITC
• Flourescein isothicyanate-Dextran40S
(Molecular weight =40000g/mol)
• Flourescein isothicyanate-Dextran2000S
(Molecular weight = 2000000g/mol).
450 500 550
0.00
0.04
0.08
0.12A
bsor
banc
e
Wavelength (nm)
0 M
10-6 M
10-5 M
10-4 M
10-3 M
10-2 M
10-1 M
[CTAB]
Absorption spectra of FITC (50 μM) at different CTAB concentration
.
500 525 550 575 6000
200
400
600
800
1000
Flu
ores
cenc
e In
tens
ity
Wavelength (nm)
0.50 nM 0.75 nm 1.0 nM 2.5 nM 5.0 nM 7.5 nM 10.0 nM 25.0 nM
[FITC]
Fluorescence spectra of FITC in aqueous solution at different concentration of the dye molecules
0 5 10 15 20 25
0
200
400
600
800
1000
Flu
ores
cenc
e In
tens
ity (
at 5
20 n
m)
[FITC] (nM)
R2 = 0.9909
Fluorescence intensity as a function of FITC concentration
Emission peak appeared in between the CTAB concentration range 1 to 10 mM
500 520 540 560 580 600
0
50
100
150W
avel
engt
h (n
m)
Wavelength (nm)
0 M
10-6 M
10-5 M
10-4 M
10-3 M
10-2 M
10-1 M
[CTAB]
500 525 550 575 6000
40
80
120F
luor
esce
nce
Inte
nsity
Wavelength (nm)
2 mM 3 mM 4 mM 5 mM 6 mM 7 mM 8 mM 9 mM 10 mM
[CTAB]
• The peak obtained at the minimum CTAB concentration of 3.0 mM.
• The emission maxima was obtained at 526 nm.
• Intensity increases linearly with the CTAB concentration.
1*10-3 2*10-3 3*10-3 4*10-3 5*10-3 6*10-3 7*10-3 8*10-3 9*10-3
-20
0
20
40
60
80
100
120
Inte
nsity
(at
526
nm
)
CTAB concentration (mol/dm3)
500 520 540 560 580 6000
10
20
30F
luo
resc
en
ce I
nte
nsi
ty
Wavelength (nm)
0.3 mM 0.4 mM 0.5 mM 0.6 mM 0.7 mM 0.8 mM 0.9 mM 1.0 mM
[CTAB]
The spectra obtained show the peak at the minimum CTAB
concentration of 0.4 mM.
Maximum intensity of the emission peak corresponding to 0.4mM
CTAB concentration was found at 520 nm.
Intensity increment with CTAB concentration occurs in a non-
linear fashion.
Change in ionic atmosphere & self quenching of probes may be
attributed as the cause for non-linearity.
500 520 540 560 580 6000
10
20
30
Flu
ore
scen
ce I
nten
sity
Wavelength (nm)
1 mM 2 mM 3 mM 4 mM 5 mM
[CTAB]
• FITC-Dextran 40S was diluted 10 times of primary concentration. It was diluted to 0.5 nM.
• Stokes’s shift appeared at CTAB concentration of 2.0 mM.
• Maximum intensity obtained at 526 nm.
• Intensity increased linearly with the increment of CTAB concentration.
1*10-3 2*10-3 3*10-3 4*10-3 5*10-3
-5
0
5
10
15
20
25
30
Inte
nsi
ty [at 526 n
m]
CTAB concentration (mol/dm3)
500 520 540 560 580 6000
10
20
30
Flu
ores
cenc
e In
tens
ity
Wavelength (nm)
2 3 4 5 6
[CTAB]
The spectra obtained show the peak at the minimum CTAB concentration
of 3 μM.
Maximum intensity of the emission peak corresponding to 3 μM CTAB
concentration was found at 515 nm.
Intensity increment with CTAB concentration occurs in a non-linear
fashion.
Change in ionic atmosphere & self quenching of probes may be attributed
as the cause for non-linearity
500 525 550 575 6000
10
20
30
40F
luor
esce
nce
Inte
nsity
Wavelength (nm)
1 mM 2 mM 3 mM 4 mM 5 mM 6 mM 7 mM 8 mM
[CTAB]
• Involves dilution of 5nM FITC-Dextran(2000S) to thousand times,
i. e., 5 pM solution was taken.
• Stokes’s shift appeared at CTAB concentration of 2.0 mM.
• Maximum intensity obtained at 546 nm.
• Intensity increased linearly with the increment of CTAB concentration.
0 2 4 6 8 10
0
5
10
15
20
25
30
35
Inte
nsi
ty [at 546 n
m]
CTAB concentration (mM)
Solution System Variable
ComponentIntensity
Incrementλem λex
FITC +Water FITC concentration Linear 516 nm 490 nm
FITC + CTAB CTAB concentration
Linear 526 nm 490 nm
FITC D 40 S + CTABCTAB
concentrationNon-linear 523 nm 490 nm
FITC D 40 S + CTAB (BACK)
CTAB concentration
Linear 526 nm 490 nm
FITC D 2000S + CTABCTAB
concentrationNon-linear 515 nm 490 nm
FITC D 2000 S+ CTAB (BACK )
CTAB concentration
Linear 546 nm 490 nm
The minimum concentration at which CTAB & FITC forms
premiceller self-assembly was determined by spectrometric method ,and
effect of sugar bulk on the self assembly was determined by correlated
studies.
The dye-surfactant interaction below the CMC of CTAB has been
characterised by UV-vis and fluorescence emission spectroscopic studies.
This study has explored several features of miceller chemistry in one
hand and versatile behavior of interaction with the surfactant used with
a fluorescence probe with increasing its bulkiness in another.
1. Rosen, M. J. Surfactants and Interfacial phenomena ; 3rd edition;Wiley-Interscience (2004).2. Gohain, B.; Dutta,R. K., Premicellar and micelle formation behavior of dye-surfactant ion-pairs In aqueous solutions: Deprotonation of dye in ion pair micelles, J. Colloid Interface Sci. 2008, 323,395-402.3.Gao, H. W.; Zhou, D. Y. Langmuir Aggregation of Fluorescein Isothiocyanate (FITC) on Cetyl Trimethylammonium Bromide (CTAB) and Application to Determination of Anionic Detergent in Sewage, Bull. Korean Chem . Soc. 2002, 23, 29-34.4. Diaz Garcia, M. E.; Sanz-Medel, A. Dye-surfactant interactions: a review, Talanta 1986, 33, 255-264. 5. Acharya, S.; Rebery B. Fluorescence Spectrometric Study of Eosin Yellow Dye-Surfactant Interactions, Arabian J. Chem. 2009, 2, 11-19.6. Lakowicz, J. R. Principles of Fluorescence Spectroscopy: Plenum Press: NewYork(1983).7. TdB Consultancy AB, www.tdbcons.se, Version: FD010AA, Date: 12/2010.8. Garćia-verdugo, I., Śanchez-Barbero, F., Soldau, K., Tobias, P. K.; Casals,C. Interaction of SP-A (surfactant protein A) with bacterial rough lipopolysaccharide (Re-LPS), and effects of SP-A on the binding of Re-LPS to CD14 and LPS-binding protein, Biochem. J. 2005, 391, 115-124.9. Determana, A. S.; Trewyn, B.G.; Lin, V. S. -Y.; Hamilton, M. N-, Narasimhana, B., Encapsulation, stabilization, and release of BSA-FITC from poly anhydride microspheres, J. Controlled Release 2004,100, 97-109. 10. Garcia-Verdugo, I.; Tanfin, Z.; Dallot, E ; Leroy, M. J.; Breuiller-Fouché, M. Surfactant Protein A Signaling Pathways in Human Uterine Smooth Muscle Cells, Biol. Reproduct. 2008, 79, 348-355.
HOD, Chemistry
All Faculty Members
Non-Teaching Staff Members
Research Scholars
4th and 3rd Semester Students
Spervisor:Prof.M.R.Islam
Co-Supervisor: Dr. Sujit Kumar Ghosh