.

vitro findings with consumer experience. In doing so, the cost and time associated with running consumer panels can be saved and allow for a more agile and successful development process of lipsticks. From the overview of lip surface biophysical properties, there are significant lessons about how lipstick products may interact with the lip surface. Surface properties, such as the ceramide profile of the lip, provide important fundamental knowledge about lip care products aimed at restoration of lip barrier function, while also meeting challenges associated with consumer comfort. Lip biophysical properties, like Young’s modulus and lip extension/contraction during motion, are important considerations for lipstick products that enhance product durability and acceptance. Existing test methods, such as adhesion tests, can be utilized to achieve these goals and act as a better predictive model through the use of appropriate substrates. Factoring in the mechanical properties of both the keratinous layer of the lips and the formulation would assist in enhancing the adhesion whilst also ensuring consumer comfort. Additionally, further investigation into the chemistry of a ceramide based surface will help optimize formulations while opening the possibility to incorporate additional benefits. In turn, these developments will be able to provide further insight into current lipstick formulations whilst also elucidating the benefits of new product innovations.

Acknowledgements

      A special thank you to Jody Ebanks and Frances San George for assisting with technical knowledge and to Qian Zheng and Charbel Bouez for their continued guidance and support.

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