SPECTROSCOPIC OF THE FORMATION OF ASSOCIATE BETWEEN IN MICRO

1. SPECTROSCOPICOF THE FORMATION OF ASSOCIATE BETWEEN IN MICRO Marta Szymula, Stanisław Radzki*, Department of Radiochemistry *Department of M. Curie-Skłodowska University,

2. INVESTIGATION EQUILIBRIUM VITAMIN C AND VITAMIN EEMULSIONS Edyta Mazur and Urszula Kubić and Colloid Chemistry Inorganic Chemistry M.C. Skłodowska Sq. 2,20-031 Lublin,Poland

3. 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 themicroenvironment present in the biological systems can contribute a great deal to the understanding of naturally occurring processes.

4. NAME SYMBOL NAME SYMBOL Tlen singlet Radical alkoxy 1 · O RO 2 Radical peroxide O · ROO Ozon 3 Radical Peroxide ROOH · OH - hydroxyperoxide (=hydroxyperoxide) 2 (=radical anion hydroxyperoxide ) Radical anion · O - peroxide 2 Oxygen dioxide H O 2 2 Radical hydroxyl · OH The most reactive chemical creature REACTIVE FORMS OF OXYGEN (ROS) Radiationion Ultrasounds Smoke of cigarette

5. VITAMIN C OXIDATION REACTION 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.

6. -TOCOPHEROL, VITAMIN E FAT-SOLUBLE VITAMIN The activity of the E-vitamers is associated with the phenolic hydroxy group, which readily undergoes oxidation.

7. -TOCOPHEROL OXIDATION REACTION α-Tocopherol oxidation by strong oxidizersleads tochroman-5,6-chinon α-Tocopherol oxidation byweek oxidizers leads to α-tokopherylo-p-chinon

8. MEMBRANE CELL MODELSOLUBILIZATION D. Chiras, Human Biology 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.

9. ANTIOXIDANTS OF VARIOUS HYDROPHILIC/HYDROPHOBIC CHARAKTER H2O H2O VITAMIN C H2O OIL H2O VITAMIN E H2O H2O H2O

10. L-Ascorbic acidis easily dissolved in themicroemulsion region of SDS, pentanol, water system

11. CALCULATIONS OF EQUILIBRIUM CONSTANTS FOR α-TOCOPHEROL BINDING TO ASCORBIC ACID

12. The values of the association constants K [L mol-1] for ascorbic acid withα-tocopherolassociates in various microemulsions

13. 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.

15. Consuming more antioxidants helps provide the body with tools to neutralize harmful free radicals.