Many different substances can increase skin permeability, allowing other molecules to pass through more easily. These substances enhance the skin's ability to absorb compounds.
Substances that Enhance Skin Permeability
According to research, over 350 molecules can enhance skin permeability through different mechanisms. These molecules fall into several categories:
- Fatty Acids and Fatty Alcohols: These are lipid-based molecules that can disrupt the skin's natural barrier, allowing better penetration.
- Alcohols and Glycols: These compounds can also disrupt the skin’s lipid layer, facilitating the passage of other molecules. Examples include ethanol and propylene glycol.
- Terpenes: These are natural compounds found in plants, some of which can increase skin permeability by affecting the skin's structure.
- Sulphoxides: Known for their ability to penetrate biological membranes, these compounds assist in delivering other substances into the skin.
- Laurocapram: This is a synthetic molecule that is highly effective at enhancing skin penetration.
- Pyrrolidones: These molecules can improve the permeation of various substances through the skin.
- Surfactants: Surfactants reduce the surface tension of liquids and can disrupt the skin’s barrier, facilitating enhanced absorption.
- Urea: This common ingredient in skincare products can also increase skin permeability.
Mechanisms of Increased Permeability
The substances listed above affect the skin barrier in different ways. Common mechanisms include:
- Disrupting the Lipid Structure: Many of these compounds, especially fatty acids, alcohols, and surfactants, can disrupt the lipid bilayer structure in the stratum corneum (the outermost layer of skin), making it less resistant to penetration.
- Increasing Hydration: Some molecules, like urea and glycols, can increase the hydration of the stratum corneum, making it more permeable.
- Interacting with Skin Proteins: Some substances might interact with proteins in the skin, altering their structure and facilitating increased permeability.
Examples of Permeability Enhancers in Products
Many products use these enhancers to help active ingredients penetrate the skin:
- Skincare Products: Many lotions and creams use fatty acids and alcohols to help moisturizers and other ingredients penetrate deeper.
- Transdermal Patches: Patches delivering medications often contain enhancers like sulphoxides or laurocapram to deliver the medication effectively.
- Topical Medications: Ointments and creams may include surfactants or urea to help active pharmaceutical ingredients reach the target site.
| Enhancer Type | Examples | Mechanism |
|---|---|---|
| Fatty acids/Fatty alcohols | Oleic acid, Cetyl alcohol | Disrupts lipid bilayer |
| Alcohols/Glycols | Ethanol, Propylene glycol | Disrupts lipid bilayer; increases hydration |
| Terpenes | Limonene, Menthol | Modifies skin structure |
| Sulphoxides | DMSO | Facilitates membrane penetration |
| Laurocapram | Azone | Highly effective penetration enhancer |
| Pyrrolidones | N-methyl-2-pyrrolidone | Improves permeation |
| Surfactants | Sodium lauryl sulfate | Reduces surface tension; disrupts skin barrier |
| Urea | Increases skin hydration |
These substances play a crucial role in skincare and medicine, allowing active ingredients to be delivered effectively through the skin.
