Oleogel architecture: how it differs from hydrogels and lamellar emulsions

Any gel is a structured system in which a liquid phase is held within a three-dimensional gelling network.

• In hydrogels, which remain one of the most common forms in topical products, the network immobilizes water.
• In oleogels, the same principle works differently: the three-dimensional framework immobilizes liquid oil. That is why an oleogel belongs to anhydrous lipid systems and differs fundamentally from both hydrogels and ordinary creams.

For topical products, this distinction matters. Hydrogels hydrate and cool well, but they are poorly suited for lipophilic actives and do not create a strong occlusive barrier. Oleogels, by contrast, address exactly those needs: they can serve as a stable medium for essential oils, provide comfort during application, and at the same time reduce water loss from the skin surface.

It is also important not to confuse oleogels with lamellar emulsions. Although both systems can support skin barrier care, their architectures differ.

• A lamellar emulsion is an emulsion system, which means it necessarily contains both water and oil, and its defining feature is the organization of emulsifiers and lipids into plate-like, layered structures that partially mimic the lipid organization of the stratum corneum.
• An oleogel, however, contains no aqueous phase: the oil is retained not at the interface of two phases, but by its own gelling network. In other words, a lamellar emulsion is still an emulsion, not an oleogel.

These distinctions are clearly illustrated by the comprehensive study by Andres Zapata Betancur and colleagues from the University of Antioquia in Colombia, published in Gels in 2026 [1]. The authors described a rational formulation strategy for oleogels. They showed that they should be viewed not as accidental mixtures or balm-like forms, but as technologically managed platforms with predefined properties.

The internal architecture of an oleogel determines its density, plasticity, thermal stability, and ability to retain and release active compounds. That is why interest in this system is driven not only by texture and sensory feel, but also by the possibility of precisely tuning topical performance through the parameters of the gelling network.

Composition, structure, and physicochemical properties of oleogels

In this work, the authors used two carrier oils — almond oil and camellia oil — and compared their behavior in systems containing three structuring agents: 12-hydroxystearic acid, sunflower wax, and rice bran wax. It is important to understand that plant waxes are not oils in the usual sense; they are obtained during the refining process, specifically the winterization of sunflower oil and rice bran oil. Unlike liquid triglyceride oils, waxes consist of fatty acid esters and high-molecular-weight alcohols, which makes them solid at room temperature and allows them to function as the structural backbone of the lipid system.

The study showed that oleogel properties depend not only on the gelling agent itself, but also on the nature of the oil phase. The oil in such a system is not an inert solvent: it actively participates in shaping the crystal network microstructure. The authors found that camellia oil, which is richer in oleic acid, promoted the formation of stronger and more rigid networks. By contrast, almond oil, which contains a higher proportion of linoleic acid, produced softer and more pliable structures. Thus, the chemical composition of the oil phase determines not only the sensory profile but also the physicochemical stability of the entire system.

Clear differences also emerged among the gelling agents themselves. Rice bran wax formed the most rigid, needle-like, and thermally stable crystals. Sunflower wax, with its plate-like crystal morphology, occupied an intermediate position in terms of strength. 12-hydroxystearic acid formed a unique dynamic network of very fine fibrils that recovered almost immediately after deformation.

For practical skincare formulation, this means that by adjusting the combination of oil and wax, one can pre-program the base’s properties — from a dense protective barrier to a light, melt-on-application texture.

Modern methods for producing and optimizing oleogels

To find the ideal component ratio, the authors used a D-optimal mixture design. This mathematical experimental design approach enables high-precision calculations of how changes in the proportions of oil, wax, and active additives affect the final product properties. Instead of manually testing thousands of combinations, the researchers used an algorithm to build a composition–property model. This made it possible to identify formulas that were very close to a commercial benchmark in terms of texture: hardness, consistency, and structural recovery.

This approach shows that modern oleogel development has moved far beyond empirical trial-and-error. Mathematical modeling enables rational control of the system’s behavior, pre-setting the desired density and ease of use, making cosmetic formulation development more predictable and efficient.

This is crucial in practice. If a denser, more stable, balm-like texture is needed, the network can be strengthened by choosing a particular structuring agent and oil phase. If softness, good spreadability, and a gentler application feel are more important, another ingredient combination can be selected. In this sense, oleogels can be designed for a specific purpose, rather than used as a universal base.

Oleogels as a platform for delivering essential oils

Incorporating essential oils into topical products always comes with technological challenges. Because they are highly volatile and sensitive to external factors, they lose activity quickly, and high concentrations in direct contact with the skin may irritate the skin. One key idea in this paper was to use oleogels as an effective system for solving these problems.

The study examined the stability of a blend of essential oils from ginger, cinnamon, tea tree, and geranium within the lipid matrix. The authors showed that the oleogel acts as an intelligent reservoir: the three-dimensional gelling network physically retains volatile molecules, protecting them from premature evaporation and oxidation. This not only stabilizes the formula during storage but also creates conditions for controlled, prolonged release of the components.

Such uniform and dosed delivery makes essential oils more predictable and safer to use, reducing the risk of abrupt skin reactions. Importantly, the inclusion of the oil blend did not disrupt the lipid network's overall architecture, confirming that oleogels are robust, technologically sound platforms for complex natural actives that are difficult to stabilize in conventional carriers.

Biological effects and safety of oleogels loaded with essential oils

In this study, the biological tests were performed not on plain oleogels, but on oleogels loaded with an essential oil blend. This system showed pronounced bactericidal activity against Staphylococcus aureus and Pseudomonas aeruginosa: after 12 hours, bacterial viability decreased by more than 99%. Thus, the antimicrobial effect applies to the loaded oleogels, not to the base lipid matrix alone.

The authors also evaluated the effect of these oleogels with essential oils on keratinocytes. At low concentrations (1–5 µg/mL of the equivalent of the essential oil blend), they observed increased cell viability and proliferation, whereas higher doses entered the cytotoxic range. This points to a therapeutic window in which the biological effect remains favorable while the risk of cell damage stays low.

The authors also emphasized that the final response is influenced not only by the essential oil blend but also by the lipid system itself. Depending on the carrier composition and its microstructure, the oleogel may amplify or attenuate the biological activity of the loaded components. For that reason, the oleogel in this study should be viewed not as a passive base but as an active carrier that contributes to antimicrobial and cellular responses.

Perspectives and conclusions: oleogels as a modern skincare tool

The results of the study show that an oleogel is not simply thickened oil, but a flexible, high-tech lipid platform. For the skincare practitioner and product developer, this system is attractive because it combines two key qualities: excellent consumer properties and high functional performance

As a consumer-facing format, oleogels address the problem of oil fluidity by providing a pleasant texture, easy spreadability, and a clear skin-care feel without excessive greasiness. By varying the combination of gelling agent and carrier oil, it is possible to create either dense protective forms or lighter, more delicate compositions.

As a functional system, the oleogel opens new possibilities for working with complex lipophilic ingredients, especially essential oils. The lipid network retains these volatile substances, protecting them from oxidation and evaporation while ensuring their uniform, controlled delivery to the skin. This approach helps preserve the functional potential of natural ingredients while reducing the risk of unwanted effects.

Overall, the ability to design oleogels for specific purposes makes them among the most promising bases for modern topical products. Their ability to combine stability, sensory comfort, and technological control over active ingredients makes oleogels among the most valuable tools in modern cosmeceuticals and aesthetic medicine.

Reference

1. Zapata Betancur A., Forero Longas F., Pulido Diaz A. Oleogel dressings for skin therapy: physicochemical and bioactive properties of cosmetic oil-based systems enriched with essential oils. Gels. 2026; 12: 248. doi:10.3390/gels12030248.