SPECTROSCOPIC OF THE FORMATION OF ASSOCIATE BETWEEN IN MICRO Marta Szymula, Stanisław Radzki*, Department of Radiochemistry *Department of M. Curie-Skłodowska University,
Dec 25, 2015
SPECTROSCOPIC OF THE FORMATION
OF ASSOCIATE BETWEEN IN MICRO
Marta Szymula, Stanisław Radzki*, Department of Radiochemistry
*Department of M. Curie-Skłodowska University,
INVESTIGATION EQUILIBRIUM VITAMIN C AND VITAMIN EEMULSIONS
Edyta Mazur and Urszula Kubićand Colloid Chemistry Inorganic ChemistryM.C. Skłodowska Sq. 2, 20-031 Lublin, Poland
PURPOSE
The main purpose of our studies included examination of association of water-soluble antioxidant ascorbic acid (vitamin C, H2A, AA) and hydrophobic α-tocopherol (α-T) in microemulsions.
It was found that activity of antioxidants depends not only on their molecular structure but also on the reaction environment. We chose microemulsion as a medium of antioxidants activity studies, having in mind the fact that many substances of hydrophilic and hydrophobic character (e.g. antioxidants) can be solved or solubilized in such a systems.
We also took into account the idea that the design of microscopic molecular assemblies which mimic the microenvironment present in the biological systems can contribute a great deal to the understanding of naturally occurring processes.
REACTIVE FORMS OF OXYGEN (ROS)
Radiationion
Ultrasounds
Smoke of cigarette
NAME
SYMBOL
NAME
SYMBOL
Tlen singlet
21O
Radical alkoxy
RO
Ozon
3O
Radical peroxide
ROO
Radical hydroxyperoxide
(=radical anion hydroxyperoxide )
2OH
Peroxide (=hydroxyperoxide)
ROOH
Radical anion peroxide
O
2
Oxygen dioxide
22OH
Radical hydroxyl
OH The most reactive chemical creature
VITAMIN C OXIDATION REACTION
O
OH OH
H
O
CH2OHOHH
O
O O
H
O
CH2OHOHH
+2H+
-2H+
+2e-
-2e-
L-ascorbic acid
L-dehydroascorbic acid
The absorption spectrum of L-ascorbic acid dissolved in water at pH 2.0 reveals a λmax of 243nm (ε=10000 L mol-1 cm-1) which undergoes a red shift to 265nm (ε=16 500 L mol-1 cm-1) when pH goes up to 7.0 as a result of ionization of the C-3-OH proton.
-TOCOPHEROL, VITAMIN E FAT-SOLUBLE VITAMIN
O
OH
CH3
CH3
CH3
CH3
CH3
CH3CH3
CH3
The activity of the E-vitamers is associated with the phenolic hydroxy group, which readily undergoes oxidation.
-TOCOPHEROL OXIDATION REACTION
O
CH3
CH3
CH3
CH3
OH
R
O
CH3
CH3
CH3
CH3
O
R
O
CH3
CH3
CH3
OCH3
OH
R
+
Utlenianie
Redukcja
+H2O
-H2O
α-Tocopherol oxidation by strong oxidizers leads to chroman-5,6-chinon
α-Tocopherol oxidation by week oxidizers leads to α-tokopherylo-p-chinon
MEMBRANE CELL MODELSOLUBILIZATION
D. Chiras, Human
Biology
ZWIĄZEKZWIĄZEKPOLARNYPOLARNY
MICELE ODWRÓCONEMICELE ODWRÓCONE
ZWIĄZEK NIEJONOWYZWIĄZEK NIEJONOWY
MICELE NORMALNEMICELE NORMALNE
ZWIĄZEK AMFOFILOWYZWIĄZEK AMFOFILOWY
SOLUBILIZATION
Microemulsions and liquid crystals are the most popular delivery systems for functional cosmetics and pharmaceutical ingredients. Aggregated systems of self-assembling molecules are able to prevent chemical degradation of the active ingredient.
Solubilization – the bringing into solution of insoluble organic substances be surfactant solution above cmc. The process involves incorporation of solubilizate into the surfactant micelle.
ANTIOXIDANTS OF VARIOUS HYDROPHILIC/HYDROPHOBIC CHARAKTER
VITAMIN CH2O
H2O
H2O
H2O
H2O
H2O
H2O
VITAMIN E
OIL
L-Ascorbic acid is easily dissolved in the microemulsion region of SDS, pentanol, water system
CALCULATIONS OF EQUILIBRIUM CONSTANTS FOR α-TOCOPHEROL BINDING TO ASCORBIC ACID
nAAAAAAAA )T-(...)T-()T-(T- T-2
T-
]T-][)T-([
])T-([
1
n
nn AA
AAK
][]T-[......]T-[]T-[1
]T-[.........]T-[]T-[0
212
211
212
212110 AAKKKKKK
KKKKKKKA
nn
nnnn
A - absorbance 0 - molecular absorbance coefficient for the starting propyl gallate 1 and K1, 2 and K2, ... , etc. - molecular absorbance coefficient an association constants for complexes with stoichiometry 1:1, 1:2, ... , etc., respectively [AA0] and [-T] - analytical concentration of ascorbic acid and α-tocopherol
The values of the association constants K [L mol-1] for ascorbic acid with α-tocopherol associates in various microemulsions
Solution composition
System K [L·mol-1]
6% SDS, 1% pentanol 93% water O/W
λ 264 nm; 26 846±16%
λ 246 nm; 25 834±24%
6% SDS, 22% pentanol 72% water bicontinous
λ 264 nm; 26 773±37%
λ 250 nm; 26 420±30%
6% SDS, 77% pentanol 17% water W/O
λ 264 nm; 106 300±6%
λ 250 nm; 82 620±7%
CONCLUSIONS•α-Tocopherol forms 1:1 molecular complexes with ascorbic acid, which appears to be due to the hydrogen bond.
•The associate formed were decomposed with time.
•Evolution of absorption spectra during the study of molecular complex formation goes in three steps through well-defined isosbestic points.
•The association constants were calculated using the curve-fitting procedure.
Consuming more antioxidants helps provide the body with tools to neutralize harmful free radicals.
200 220 240 260 280 300 320 340
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
1% pentanol 6% SDS93% water
Wavelenght [nm]A
bso
rb
an
ce
Vitamin C + vitamin E
264 nm
292 nm
202-212 nm
200 220 240 260 280 300 320 340
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
22% pentanol 6% SDS 72% water
Wavelenght [nm]
Ab
so
rb
an
ce
Vitamin C + vitamin E
264 nm
292 nm
202- 230 nm
200 220 240 260 280 300 320 340
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
77% pentanol 6% SDS 17% water
Wavelenght [nm]
Ab
so
rb
an
ce
Vitamin C + vitamin E
264 nm
292 nm
202- 230 nm
Vitamin C + vitamin E
0 5 10 15 20 25
0.0
0.5
1.0
1.5
2.0
Vitamin E CM.
105
Ab
so
rb
an
ce
77% pentanol 6% SDS17% water
264 nmRsq = 0.991
K = 106300±6%
250 nmRsq = 0.999
K = 82020±7%
Vitamin C + vitamin E
0 5 10 15 20 25
0.0
0.5
1.0
1.5
2.0
Vitamin E CM.
105
Ab
so
rb
an
ce
1% pentanol 6% SDS93% water
264 nmRsq = 0.918
K = 26846±16%
246 nmRsq = 0.958
K = 25834±24%
Vitamin C + vitamin E
0 5 10 15 20 25
0.0
0.5
1.0
1.5
2.0
Vitamin E CM.
105
Ab
so
rb
an
ce
22% pentanol 6% SDS72% water
264 nmRsq = 0.842
K = 26773±37%
250 nmRsq = 0.883
K = 26420±30%
200 220 240 260 280 300 320 340
0
1
2
3
4
Wavelenght [nm]A
bso
rb
an
ce
1% pentanol 6% SDS 93% water
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Ab
so
rb
an
ce
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
220 nm, 0 h 264 nm, 0 h 292 nm, 0 h
De Job's plot for the vitamin C and vitamin E system
x vitamin E
200 220 240 260 280 300 320 340
0
1
2
3
4
Wavelength [nm]
Ab
so
rb
an
ce
22% pentanol 6% SDS 72% water
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Ab
so
rb
an
ce
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4 220 nm, 0 h 264 nm, 0 h 292 nm, 0 h
De Job's plot for the vitamin C and vitamin E system
x vitamin E
200 220 240 260 280 300 320 340
0
1
2
3
4
Wavelength [nm]
Ab
so
rb
an
ce
x vitamin E
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Ab
so
rb
an
ce
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
220 nm, 24 h264 nm, 24 h292 nm, 24 h
De Job's plot for the vitamin C and vitamin E system
77% pentanol 6% SDS 17% water
200 220 240 260 280 300 320 340
0
1
2
3
4
Wavelenght [nm]A
bso
rb
an
ce
1% pentanol 6% SDS 93% water
x vitamin E
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Ab
so
rb
an
ce
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
220 nm, 24 h264 nm, 24 h292 nm, 24 h
De Job's plot for the vitamin C and vitamin E system
200 220 240 260 280 300 320 340
0
1
2
3
4
Wavelength [nm]
Ab
so
rb
an
ce
x vitamin E
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Ab
so
rb
an
ce
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
220 nm, 24 h264 nm, 24 h292 nm, 24 h
De Job's plot for the vitamin C and vitamin E system
22% pentanol 6% SDS 72% water
200 220 240 260 280 300 320 340
0
1
2
3
4
Wavelength [nm]
Ab
so
rb
an
ce
x vitamin E
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Ab
so
rb
an
ce
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
220 nm, 24 h264 nm, 24 h292 nm, 24 h
De Job's plot for the vitamin C and vitamin E system
77% pentanol 6% SDS 17% water