Exploring The Mechanisms Of The Olive Oil Microemulsion Area Increased By Vitamin E Succinate And Application It In Cosmetic

Objective:It was unexpectedly found that the microemulsion area of olive oil was significantly increased after loading vitamin E succinate,menthol,chlorhexidine acetate,and propylene glycol into microemulsion in the process of designing a kind of olive oil bacteriostatic body lotion.The purpose of this paper is to find the ingredients which increased the olive oil microemulsion area and to reveal its mechanism and to develop a microemulsion carrier with low surfactant amount to improve its safety.Then it was used as a carrier for preparing microemulsion body lotion and sunscreen.Methods:?1?Through single factor examination,the components that increased the microemulsion area of olive oil were investigated;and its mechanisms were revealed by determination of oil-water interfacial tension and physicochemical properties of microemulsion,which is to design a kind of olive oil microemulsion carrier with low surfactant amount for the development of cosmetics;the microemulsion carrier was characterized by measuring appearance,pH,particle size,zeta potential,viscosity,turbidity and observing the Transmission Electron Micrographs;the type of microemulsion carrier was judged by the results of conductivity and staining.?2?A moisturizing and antibacterial body lotion was prepared with olive oil/vitamin E succinate microemulsion as carrier.It was characterized by measuring pH,particle size,zeta potential,viscosity and observing the Transmission Electron Micrographs,then its stability and safety were investigated;its moisturizing effect was evaluated against commercially available vitamin E anti-cracking and anti-bacterial olive oil;With the chlorhexidine acetate water solution as reference group,E.coli and S.aureus were selected to evaluate the influence of microemulsion carrier on the antibacterial effect of chlorhexidine acetate.?3?We prepared a TiO₂ sunscreen lotion with olive oil/vitamin E succinate microemulsion as carrier.Firstly,we evaluated the physicochemical properties and safety of homemade sunscreen lotion.Secondly,we evaluated the ultraviolet protection effect of TiO₂ and homemade TiO₂ sunscreen lotion by designing a method for determining the ultraviolet shielding effect of granular TiO₂ with gel dispersion method.Finally,with Japan Dr line whitening physical sunscreen cream and Olay oil water nourishing sunscreen whitening cream as acommercial reference groups,and common cream-type sunscreen as the carrier reference group,the sensory evaluation test of 15 indicators in homemade microemulsion sunscreen lotion was conducted by fuzzy evaluation method.Results:?1?Vitamin E succinate was the factor that increased the microemulsion area of olive oil.It combined with olive oil by directely inserting oleic acid,which is the main component of olive oil.This increased the polar region of oil phase,so lowered the oil-water interfacial tension,increased the zeta potential and improved microemulsion interfacial stability,and then increased the oil-water microemulsion area.The best compounded ratio of olive oil and vitamin E succinate was 6:1.The microemulsion carrier formulation was 3.43%olive oil,0.57%vitamin E succinate,5%polyoxyethylene 40 hydrogenated castor oil,1%Span 80,and 90%water.Its microemulsion type was oil-in-water type;its particle size was less than 100 nm;PDI was less than 0.2;viscosity was less than 100 mPa·s;and the particles were rounded under electron microscope,which were consistent with microemulsion characteristics.The appearance of this product was clear and transparent;the pH?6.00±0.05?was slightly acidic and suitable for human skin pH environment;so it can be used as a carrier for the development of cosmetics.?2?The moisturizing antibacterial body lotion used olive oil/vitamin E succinate microemulsion as carrier,and its formulation was 3.43%olive oil,0.57%vitamin E succinate,5%polyoxyethylene 40 hydrogenated castor oil,1%Span 80,0.08%chlorhexidine acetate,0.2%menthol,5%glycerin,0.1%phenoxyethanol,2%carbomer,82.62%water.Its viscosity was?26.71±0.26?Pa·s,which was easy to apply to the skin;the pH?6.23±0.06?was suitable for skin pH environment;the Zeta potential?-19.2±0.52mV?showed a certain double electricity Layer stability;the particles were rounded under electron microscope and the particle size was?41.26±0.58?nm.All of these were consistent with the characteristics of microemulsion.The results of Guinea pig test and human patch test showed that the body lotion was safe;the results of room temperature,high-low temperature tests showed that it was stable;compared with the effect of commercially available vitamin E anti-cracking and antibacterial olive oil,the moisturizing effect of self-made body lotion was not lower than the commercial body lotion.The self-made body lotion can inhibit both S.aureus and E.coli,the minimum inhibitory concentration for them were 7.33×10^-4 mg·ml^-1 and2.93×10^-3 mg·ml^-1,which was 50.14%and 50%less than that of the water solution,respectively.All of these showed the microemulsion carrier can promote the antibacterial effect of chlorhexidine acetate.?3?The TiO₂ sunscreen lotion used olive oil/vitamin E succinate microemulsion as carrier and its formulation was 3.43%olive oil,0.57%vitamin E succinate,5%polyoxyethylene 40 hydrogenated castor oil,1%Span 80,0.1%phenoxyethanol,0.5%carbomer,0.5%sodium hyaluronate,0.5%sodium alginate,1%TiO₂,87.4%water.The viscosity was?10.93±0.08?Pa·s,which was easy to apply to the skin;the pH?5.68±0.08?was milder and suitable for Human skin pH environment;safety test result was negative;UV absorption spectra of TiO₂ and TiO₂ sunscreen lotion showed that homemade sunscreen lotion can achieve full-frequency protection in both UVA and UVB bands.The TiO₂ sunscreen lotion was lighter and easier to be absorbed than common cream-type sunscreen and commercially available physical sunscreen,and it had the advantages of good moisture retention and being easy to remove makeup.This result indicated that the microemulsion carrier can effectively improve the shortcomings of the physical sunscreen being thick and difficult to absorb.Conclusion:Vitamin E succinate can significantly increase the microemulsion area of olive oil.This discovery can greatly reduce the amount of surfactant in olive oil microemulsion,and solve the bottleneck problem of using mass surfactant,when microemulsion is used as the carrier of cosmetic and transdermal drug.Meanwhile it can promote the application of microemulsion products in the market.