Pickering Emulsion Composition for Stable Surfactant-Free Topical Delivery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing emulsions for topical drug delivery are thermodynamically unstable, leading to creaming and inhomogeneity, and often require synthetic surfactants that cause skin irritation and environmental issues.
Innovation Solution
A biodegradable and biocompatible oil-in-water Pickering emulsion stabilized by polyester nanoparticles and hyaluronan, which prevents coalescence and creaming, eliminating the need for surfactants and providing improved stability and skin compatibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If synthetic surfactants are used to stabilize emulsions, then emulsion stability is improved, but skin irritation and environmental toxicity increase
Solution Approach 1:
The patent uses solid particles (nanoparticles of hydrophilic polymers such as chitosan, gelatin, or albumin) as intermediary stabilizers at the oil-water interface, replacing synthetic surfactants. These biocompatible particles form a physical barrier that prevents coalescence without causing skin irritation or environmental toxicity, thus resolving the contradiction between stability and harmful effects.
Solution Approach 2:
The patent changes the stabilization mechanism from chemical (synthetic surfactants) to physical (solid particle adsorption at interface). By using nanoparticles with specific surface properties that adsorb at the oil-water interface, the system achieves thermodynamic stability through a different physical-chemical parameter regime that is inherently biocompatible.
2Stability of the object's composition
If solid particles are used to stabilize emulsions (Pickering emulsions), then long-term stability is improved, but creaming tendency increases
Solution Approach 1:
The patent applies local quality by using a combination of different types of solid particles with complementary properties. Hydrophilic particles stabilize the external aqueous phase while hydrophobic particles stabilize the internal oil phase, creating localized stabilization at different regions of the emulsion structure that prevents overall creaming.
Solution Approach 2:
The patent employs composite stabilization systems using multiple types of nanoparticles (e.g., chitosan nanoparticles combined with gelatin nanoparticles, or albumin nanoparticles with other biopolymers). This composite approach creates a synergistic effect where different particle types work together to prevent both coalescence and creaming, achieving long-term stability without the creaming tendency of single-particle systems.
3Reliability
If multiple therapeutic agents are delivered separately, then treatment efficacy is improved, but patient compliance and application complexity increase
Solution Approach 1:
The patent merges multiple therapeutic agents (e.g., anti-inflammatory agents like corticosteroids and immunosuppressive agents like calcineurin inhibitors) into a single emulsion formulation. Different agents are encapsulated in different phases (oil phase, aqueous phase, or within nanoparticles), allowing simultaneous delivery through one application, thereby maintaining treatment efficacy while significantly improving patient compliance.
Solution Approach 2:
The emulsion system is designed as a universal delivery platform that can accommodate multiple types of therapeutic agents with different solubilities and stability requirements. The multi-phase structure with nanoparticle stabilization provides a universal mechanism for protecting and delivering various drugs (hydrophobic, hydrophilic, and amphiphilic) simultaneously, making the formulation adaptable to different treatment protocols.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The emulsion maintains stability for at least 24 hours, enhances skin penetration and hydration, and offers superior therapeutic efficacy with a pleasant texture, making it effective for treating dermatologic pathologies like psoriasis.
Implementation Method 1
These emulsions are called Pickering emulsions and were described more than a century ago by Pickering and Ramsden. They exhibit a long-term stability thanks to solid particles that create a physical barrier against destabilization phenomena, e.g. coalescence.
Implementation Method 2
In this range, hyaluronan is predominantly in the ionized form (e.g. as sodium hyaluronate) and therefore provides its thickening effect the most efficiently.
Implementation Method 3
In the herein disclosed emulsion, one role of the nanoparticles is to stabilize the emulsion by preventing or slowing down coalescence of the oil droplets and/or Ostwald ripening.
Implementation Method 4
an improved dermal penetration of drugs
Data Source
AI summary
Oil-in-water Pickering emulsion comprising: an oil phase comprising a first therapeutic agent, an aqueous phase, polyester nanoparticles comprising a second therapeutic agent, wherein the oil phase is in the form of droplets and is dispersed in a continuous aqueous phase, and wherein at least a portion of the nanoparticles are localized at an interface between the oil phase and the aqueous phase, characterized in that the aqueous phase comprises hyaluronan. This new emulsion allows the topical treatment of inflammatory dermatoses such as psoriasis, atopic dermatitis or prurigo, benign skin inflammations such as inflammatory acne, scalp pathologies such asalopecia, dermo-cosmetic conditions, such as very dry irritable skin, tumor pathologies such as mycosis fungoides (indolent cutaneous T lymphoma) or cutaneous mastocytosis (accumulation and abnormal proliferation of mast cells in the dermis, with intense pruritus), and fibrosing pathologies such as keloids (raised, pruritic dystrophic scars, which have the particularity of not regressing spontaneously and of being able to extend beyond the traumatic/injured area).