Transdermal Nanoparticles
— How Nanostructured Delivery Systems Can Transport Active Ingredients Deeper into the Skin
Liposomes, solid lipid nanoparticles, and transfersomes promise what classic emulsions often fail to deliver: bringing active ingredients precisely where they are needed. What science says about transdermal nanocarrier systems.
Nanoscale transdermal drug delivery systems are among the most intensely researched fields in modern cosmetic science. The underlying idea is fundamental: conventional formulations often fail because active substances do not penetrate the stratum corneum barrier in sufficient concentration—nanostructured delivery systems aim to address precisely this limitation.
In scientific literature, various nanoparticle architectures are discussed, including liposomes, niosomes, solid lipid nanoparticles (SLN), polymeric nanoparticles, and transfersomes. Each of these platforms exhibits specific physicochemical properties that can influence penetration behavior and active ingredient release kinetics differently. For the next generation of facial care, controlled, depth-selective active ingredient delivery is considered one of the decisive differentiating parameters.
Mechanism of Action
Nanoparticles interact with the skin via several, sometimes parallel, pathways. Research distinguishes intercellular, transcellular, and follicular penetration routes—the latter being particularly relevant for particles in the 20–200 nm range. The interplay of particle size, surface charge, lipophilicity, and carrier matrix determines which pathway dominates and at what depth the active ingredient is released.
Hair follicles and sebaceous gland openings represent so-called "shunt pathways" that reach deeper into the dermis than transepidermal diffusion. Nanoparticles with a diameter of approx. 20–200 nm can preferentially utilize these channels, as shown by studies with fluorescently labeled liposomes. This mechanism is particularly relevant for regions with high follicular density—such as the face—and can serve as a depot mechanism for delayed release.
Lipid-based nanoparticles—especially liposomes and solid lipid nanoparticles—can fuse with the lipid lamellae of the stratum corneum or temporarily alter their packing density. This fluidization of barrier lipids can be described in the literature as a "thermodynamic enhancer effect": the encapsulated active ingredient achieves a higher concentration gradient at the barrier interface and thus diffuses more efficiently. At the same time, the reversibility of this interaction is a crucial safety aspect that distinguishes nanoliposomes from more aggressive chemical penetration enhancers.
A central advantage of nanostructured carrier systems lies in programmable active ingredient release. By varying the shell materials—such as PLA, PLGA, or chitosan—the release period can be adjusted from a few hours to several days. This opens up possibilities for chronobiologically oriented formulations, where active ingredients are released time-of-day or pH-dependently—an approach that is gaining increasing scientific attention in the context of skin chronobiology and is conceptually adopted by NATURFACTOR® in time-controlled active ingredient delivery.
Forms of Appearance
The penetration depth of an active ingredient does not depend solely on its concentration in the formulation—the physicochemical compatibility between the carrier system and the skin barrier is crucial. Even highly concentrated raw materials can remain at the stratum corneum interface without an adequate carrier matrix. The combination of particle size, surface charge, and lipid composition determines whether an active ingredient acts where it should—and for how long.
What This Means for Skincare
- Formulations with lipid-compatible carrier systems that do not permanently destabilize the stratum corneum lipid matrix
- Sequential application: lighter, aqueous textures before richer emulsions to optimize penetration order
- Evening application of nanocarrier systems, as nighttime cell renewal rate and increased skin temperature can promote absorption
- Overlapping multiple penetration-enhancing systems simultaneously, which can overload barrier function
- Mechanical over-rubbing during massage, which can destabilize nanostructured vesicles and disrupt controlled release
- Combination with strongly alkaline or acidic cleansers immediately before application, as pH extremes affect particle stability
The NATURFACTOR® Porcelain Skin Serum supports the skin's active daytime phase with the Bioactive Infusion Complex™—an approach aimed at targeted, layer-by-layer active ingredient delivery and integrating lipid-compatible carrier structures to guide active ingredients to relevant skin depths without compromising the natural skin barrier. For the night, when the skin's regeneration rate reaches its daily peak and barrier permeability is slightly increased, NATURFACTOR® formulates the Blue Crystal Drops as a night care product, adapted to the skin's chronobiologically altered receptiveness according to the principle of Chrono-Peptide formulation.
For specific skin concerns – such as persistent irritation or hypersensitivity reactions after using nano-based products – a specialist dermatological assessment should be sought.
Frequently Asked Questions
Are nanoparticles in cosmetics safe for daily use?
The safety of cosmetic nanoparticles is regulated by EU Cosmetic Regulation 1223/2009, which mandates notification for nanomaterials. The SCCS (Scientific Committee on Consumer Safety) evaluates nanomaterials individually within safety assessments. Current research suggests that most topically applied nanoparticles—especially liposomes and SLN—do not systemically permeate intact skin. Different conditions may apply to compromised skin barriers, which is why caution is advised for eczema or active dermatitis.
Which active ingredients particularly benefit from nanostructured carriers?
Unstable or poorly penetrating active ingredients show the greatest benefit from nanoencapsulation. These include retinol and its plant-based alternatives like bakuchiol, oxidation-sensitive antioxidants, lipophilic ceramides, and certain peptides that can hydrolyze on the surface without a carrier. Active ingredients like ectoin or ferulic acid can also benefit from a stabilizing carrier matrix that preserves their biological activity until they reach the target structure.
How do I know if a product really contains nanostructured carrier systems?
In the EU, nanomaterials must be declared in the INCI list with the addition "[nano]" after the active ingredient name. Furthermore, terms such as "liposomes," "niosomes," "SLN," "nanocapsule," or "encapsulated" in product communication indicate corresponding carrier architectures. Independent certified laboratory analyses—such as DLS measurements (dynamic light scattering) for particle size determination—offer the most precise verification. Seriousness is also indicated when manufacturers communicate about ingredient integrity and formulation transparency.
Can the order of application influence the effect of nanocarriers?
Yes, and this aspect is often underestimated in formulation science. Double cleansing before application removes sebum and creates a more even surface for active ingredient penetration. The application of a balancing toner can shift the skin surface pH to a range more favorable for nanoparticle stability. Subsequently, nanocarrier-based serums should be applied before thicker emulsions, as occlusive layers can affect downstream penetration kinetics. Further information can be found in the Application Guide.
- Müller, R. H., Radtke, M. & Wissing, S. A. (2002). Solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) in cosmetic and dermatological preparations. Advanced Drug Delivery Reviews, 54(Suppl 1), S131–S155.
- Prow, T. W., Grice, J. E., Lin, L. L., Faye, R., Butler, M., Becker, W., Wurm, E. M. T., Yoong, C., Robertson, T. A., Soyer, H. P. & Roberts, M. S. (2011). Nanoparticles and microparticles for skin drug delivery. Advanced Drug Delivery Reviews, 63(6), 470–491.
- Escobar-Chávez, J. J., Merino-Sanjuán, V., López-Cervantes, M., Urban-Morlan, Z., Piñón-Segundo, E., Quintanar-Guerrero, D. & Ganem-Quintanar, A. (2008). The tape-stripping technique as a method for drug quantification in skin. Journal of Pharmacy & Pharmaceutical Sciences, 11(1), 104–130.
- Lademann, J., Richter, H., Teichmann, A., Otberg, N., Blume-Peytavi, U., Luengo, J., Weiß, B., Schaefer, U. F., Lehr, C.-M., Wepf, R. & Sterry, W. (2007). Nanoparticles — An efficient carrier for drug delivery into the hair follicles. European Journal of Pharmaceutics and Biopharmaceutics, 66(2), 159–164.
- Benson, H. A. E. (2006). Transfersomes for transdermal drug delivery. Expert Opinion on Drug Delivery, 3(6), 727–737.
This article is for informational purposes only and does not constitute medical advice. For specific skin concerns, we recommend consulting a dermatologist.
