Abstract:

With the rapid development of the cosmetics market and the deep affection from Oriental women for “whitening”, whitening cosmetics have become the focus of consumers and cosmetics companies. With the development of science and technology and the release of the “Regulations on Supervision and Administration of Cosmetics” in 2020, efficacy evaluation has become one of the key links in the research and development and marketing of cosmetics. Melanocytes produce melanin, which is transfered from the dendrites of melanocytes to keratinocytes, and finally follows the movement of epidermal cells to the stratum corneum to form color spots or to affect the skin color. Based on the mechanism of melanin synthesis and transportation, the evaluation methods of whitening efficacy were summarized and its development trend was put forward. The evaluation methods of whitening efficacy can be divided into physicochemical method, biochemical method, cell biology method and in vivo experiment. The principle and characteristics of 3D skin model, multiphoton imaging technology and other cutting-edge technologies are emphatically introduced, as well as some improvements in the original whitening efficacy evaluation model or method. In general, the evaluation methods of whitening efficacy will develop towards the combination of biotechnology, computer technology, high-tech instruments and skin physiology that are not easily affected by individual differences in the future, and will develop from single to multiple methods guided by mechanism. In addition, cosmetic producers should also improve their own technology and innovate more products. In the future, more and more excellent technologies and models are also needed to be applied to the whitening efficacy evaluation, so as to create a good development environment for the whole industry.

Key words: whitening, whitening efficacy evaluation, melanin synthesis, melanin transport, regulations