Expert consensus on the technical specifications of the in vitro skin penetration test of cosmetic product by Franz diffusion cell

Diffusion cell test is one of the most commonly used in vitro model to detect the percutaneous absorption of cosmetic ingredients. Although PRC State Administration of Quality Supervision and Quarantine has issued the guideline for the in vitro test method for the percutaneous absorption of drug molecules, there is still a lack of guideline for the percutaneous absorption test of cosmetic components. In order to improve the standardized level and make the in vitro percutaneous absorption test of cosmetic ingredients more comparable, based on the international and domestic experience, Transdermal Drug Delivery Committee of the World Federation of Chinese Medicine Societies organized the experts to discuss and formed this consensus as reference for the percutaneous absorption test of cosmetic components. To standardize the in vitro diffusion cell test technique for transdermal penetration of functional cosmetic ingredients, the Transdermal Drug Delivery Professional Committee of the World Federation of Societies of Traditional Chinese Medicine has organized many discussions among experts. The expert group established this expert consensus by integrating international requirements, domestic practice, and the experience of experts. This consensus provides technical operation recommendations for the detection of cosmetic percutaneous permeation in in vitro diffusion cells to reduce the differences between studies. Cosmetic formulations with different compositions and types may show different release kinetics, and this consensus does not cover all possible situations.