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Natural Jojoba Oil Enhances Skin Permeation of Retinol

A new study published in Clinical, Cosmetic and Investigational Dermatology looks at the potential of jojoba oil to enhance retinol penetration in skin.

Sebastien Massard, Vantage Specialty Chemicals04.21.23

Figure 1: Comparison of typical chemical structures of key components of jojoba oil, human sebum and vegetable oil.

Figure 2: Graph of Area Under the Curve (AUC) units for Formulations 1-3 eluted through the PAMPA.

Retinol is one of the most well-known topical skin care active ingredients. However, retinol can have a dehydrating effect on the skin which, over time, may lead to increased skin erythema and flaking. Technologies that enhance the skin permeability of retinol may allow formulators who use retinol to lower the active concentration of the molecule which can help to mitigate the skin dehydrating effects.

The skin’s stratum corneum is comprised of keratin proteins (corneocytes) that act somewhat like bricks sitting inside a lipid matrix (mortar) that acts like the cement in a wall. To effectively improve the delivery of active ingredients, it is critical to have technologies that can soften the lipid mortar to allow actives to slip around the keratin-based “bricks.” Jojoba oil wax esters share very common similarity to the skin’s sebaceous lipids. As such, jojoba oil can enhance the passive penetration of lipophilic active ingredients allowing for improved penetration of solubilized actives.

A recently published paper by Vantage Specialty Chemicals (Vantage), using a well-established skin testing model called skin-PAMPA (which creates an artificial skin-like model of the skin’s lipid barrier for testing purposes), demonstrated that jojoba oil can improve the skin penetration of retinol.¹ When ingredients soften the lipids in the testing model, enhancement of skin permeation of skin care actives, like retinol, are improved and measured. In the work published by Vantage, three formulations were tested: the first was formulated with 10% jojoba oil without retinol, the second was formulated with 1% retinol and 9% soybean oil and the third was formulated with 1% retinol and 9% jojoba oil.

The amount of retinol that could permeate through the skin-PAMPA testing model was determined via HPLC analysis by measuring the area under the curve.

Natural jojoba oil, formulated into creams containing 1.0% retinol, showed an improvement in skin permeation of retinol by 40-fold compared to similar formulations containing retinol that did not contain jojoba oil. Studies also indicated that a typical vegetable triglyceride oil, in this case soybean oil, did not have this same skin permeation-improving feature. This comparison demonstrates that jojoba oil aids in active delivery, whereas typical vegetable oils do not demonstrate this behavior.

It is believed that this similarity to human sebum is one principal reason the jojoba oil can improve the delivery of retinol into the skin. By improving the ability to deliver retinol to the skin, formulators using natural jojoba oil may reduce the amount of formulated retinol. Aside from its very well-known skin benefits, retinol is known to have skin dehydrating effects. Combined further with the previously known benefits for skin moisturization that jojoba oil provides, jojoba oil is proving to be a more versatile component of finished formulations than previously known.

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