Abstract The purpose of the study was to prepare a stable multiple emulsion system containing two skin antiaging agents using a natural oil vitamin C, known to be a very unstable ingredient and is decomposed in the presence of oxygen, was entrapped in the internal aqueous phase of w/o/w multiple emulsion. In this way, vitamin C is expected to exhibit slow release and the effect of vitamin C can be improved as it has been protected from the external environment. The other ingredient, which is a product of wheat protein was also used as an antiaging agent. Both of the ingredients increase the synthesis of collagen fibers in the dermis. Therefore, a synergystic effect can be produced by using the two ingredients in one formulation. In this study, multiple emulsions were prepared by the two-step emulsification method. Basic formulation containing no active material and a formulation containing vitamin C in the internal aqueous phase and wheat protein in the oily phase were prepared. The oil selected was macadamia nut oil since it contains a high quantity of palmitoleic acid which is the natural ingredient of the young skin. Basic formulation as well as the formulation containing active ingredients were stored at different accelerated conditions for six months and characterized. Globule size, pH, viscosity and physical changes were tested to characterize the emulsion systems. Basic emulsion was found to be more stable at all the different conditions than the formulation containing the active ingredients. Özet Bu çalismanin amaci, dogal bir yag kullanarak, iki farkli cilt yaslanmasini geciktirici madde içeren kararli emülsiyon sistemini hazirlamaktir. Çok kararsiz ve oksijen varliginda yapisinin parçalandigi bilinen vitamin C, s/y/s çoklu emülsiyonun iç fazina katilmistir. Bu sekilde, vitamin C’nin yavas salim göstermesi ve çevresel etkenlerden korundugu için etkisinin iyilestirilmesi beklenebilir. Yaslanmayi geciktirici olarak kullanilan diger madde bugday proteini ürünüdür. Her iki madde de dermis’deki kolajen liflerinin sentezini arttirir. Dolayisiyla, tek formülasyonda iki maddeyi kullanarak sinerjik etki olusturulabilir. Bu çalismada, çoklu emülsiyonlar iki-basamakli emülsiyon olusturma yöntemi ile hazirlanmistir. Hazirlanan emülsiyonlar etkin madde içermeyen temel formülasyon ve iç fazinda vitamin C, dis fazinda ise bugday proteini içeren formülasyonlardir. Seçilen yag, genç cildin dogal bileseni olan ve palmitoleik asiti yüksek miktarda içeren makademia findik yagidir. Temel formülasyon ve etkin maddeleri içeren formülasyon, farkli hizlandirilmis kosullarda 6 ay saklanmis ve özellikleri belirlenmistir. Emülsiyon sistemlerin özelliklerini belirlemek için damlacik boyutu, pH, viskozite ve fiziksel degisimler test edilmistir. Temel emülsiyonun tüm kosullarda etkin maddeleri içeren formülasyondan daha kararli oldugu bulunmustur.

Keywords: multiple emulsion, vitamin C, wheat protein, physical properties