奈米科技是目前最熱門的技術之一，隨著奈米技術的興起，也為傳統化妝品技術帶來革命性的變化。長久以來，無論局部外用藥物或化妝品，一直努力尋求更有效的皮膚傳輸方式，同時也致力於提高某些不穩定或易氧化成份的穩定性。有些文獻指出奈米技術的開發，如微脂粒技術、奈米乳化技術或奈米膠囊化技術等，可以克服過去活性物質不穩定或油性成份黏膩不易吸收等問題。同時由於活性成份粒子微小化之後，更容易穿透皮膚，使其達到更好的吸收效果。有些研究指出，奈米化後之安定性受奧士瓦熟成（Ostwald Ripening）及凡得瓦爾力（Van der Waals force）影響甚鉅，其可能造成產品絮凝（Flocculation），分層（Creaming）、聚結(Coalescence)等不安定因素，以及奈米乳化高壓過程中可能造成成份分解破壞，皆須考量。本研究利用高壓均質方式將含美白成分之配方奈米乳化為前提，針對製備方法及其性質做一探討，再藉由儀器測試其安定性、安全性及有效弁鄔妗禲A藉此研究來確認是否達到我們研究的目標。
本研究利用奈米技術所研發的化妝品，主要是將化妝品基劑，如氨基酸、硬脂酸酯、鮫鯊烷、三甘油酯、荷荷葩油、醇類、純水及有效成分如α-熊果素(α-Arbutin )、神經醯胺( Ceramide)、輔酶Q10、維他命C酯等、以高壓均質方式，壓力控制50~100Mpa，加工次數2~8次處理成為奈米結構，其中壓力大小、乳化劑及油脂選擇、及加工數等，皆會影響其粒徑大小及安定性。
配方篩選後，其粒徑大小約在60~100nm之間，此外亦發現高壓均質的配方，不易孳生細菌，達到物理性防腐的目的，將可使奈米化的附加價值更加提升至不含防腐劑的訴求。再則因為利用高壓製程的關係，研究以HPLC計算回收率，不管有沒有經過高壓均質的產物回收率在98~104%，均在合乎規定的範圍之間。再搭配耐受性測試，目標以-10℃、25℃、45℃三種溫度測試，測其安定性，以目測結果並無分層及嚴重霧化現象，以3000 rpm，離心15分鐘亦無分層現象。藉由膠體粒子穩定測試及電導度，測試其轉相法（PIT法）與高壓均質法之奈米穩定性，比較其差異性，其相圖在溫度與電壓值倒數（1/V）或與電導度值間有明顯差異，轉相法在轉相溫度以上時，會有明顯不安定現象，高壓均質法對溫度則相對安定。在MTT細胞毒性研究中，我們發現傳統製程與奈米製程之產品，在相同濃度時對B16黑色素細胞之毒性相當，顯示並不會因劑型差異，而使毒性增高。微生物驗證其劑型差異是否會明顯提高微生物增生率，結果發現傳統製程較易受微生物污染，奈米劑型有其一定的抗微生物污染性。在經皮吸收實驗過程研究發現，奈米乳化製品中之活性物質穿透人工皮膚細胞之速率遠高於傳統製品。以Lab色度系統測試美白效能方面，雖然測試時間較短，但比起美白精華液略有較好之成效。 Nano-science is the one of the most popular know-how at present. With the nanotechnology rise and development, it brings the revolutionary change for traditional cosmetics technology. No matter the localized medicine for external use and cosmetics has been looking for more effective delivery systems. In the meantime, the stability of cosmetic ingredients was improved. The development of nanotechnology from some searches shows the liposome、nanoemulsion or nanocapsule could overcome the difficulties of the unstability and unabsorbability of active material and oil ingredient sticky . It will approach the best absorb effect after the particle was miniaturized and absorbable easily by skin. Some researches show that Ostwald Ripening and Van der Waals force significantly affected the stability of nanoemulsion. It must be considered that the unstable elements of flocculation、creaming、coalescence, and ingredients could be destroyed and breakdown in the process of nanoemulsion by high pressure. To evaluation preparation method and characteristics of nanoemulsion cosmetics, we prepare some cosmetics containing whitening ingredient using high pressure homogenizer .To confirm the goal of our research, the stability, safety and effectively of nanoemulsion product were evaluated by relative instruments.
The nanoemulsion product, having basis ingredients such as amino acid、stearate ester、squalane、triglycerides、jojoba oil、alcohols、aqua and other effective materials such as ?arbutin、ceramide、Q10、vitamin C ester, is manufactured by optimum condition (50~100Mpa and 2~8 times)using high pressure by high homogenizer. Pressure、emulsifying agent、oil type and times of procedure will influence the particle size and stability.
The bacteria are not multiplied in the nanoemulsion product when the particle size of oil droplet falls in between 60nm and 100nm. It has additional value of preservative function. To evaluate the recovery of the ingredient content of cosmetics obtained through high-pressure homogenizer, we use HPLC to determine the active material content. It is found that the recovery rate of active material is 98~104%.
The stabilities of nanoemulsion products are carried out by three different temperatures （-10℃、25℃、45℃）and the result is satisfied （without stratification and nebulization）. Colloidal particle stability and conductance tests were used to compare the differences of nanoemulsion products obtained through PIT or high-pressure methods. PIT method has obvious unstable state when the phase inverse temperature is arrived but the product of high-pressure method is stable for temperature. Both of conventional emulsion and nanoemulsion products also show similar toxicity to B16 melanin cells using MTT assay. It is also found that conventional emulsion product is polluted by microorganism easier than nanoemulsion product. In percutaneous absorption experiment, we found that the quantity of active material of nanoemulsion product is higher than that of convention emulsion product crossing artificial skin within the same period. LAB chrominance instrument was used to assess the whitening efficiency. As a result of short term, we found that the effect of nanoemulsion product is better than that of convention whitening essence fluid.
