SalSphere®

Sub-micron spheres (1-3 microns) are typically used to stabilize ingredients, suspend active ingredients in water, and enable flawless formulation and cost-effective production.  SalSphere® technology is a solution for many natural extracts that are sensitive to oxidation, tend to change color, degrade over time, and generally are not water-soluble.

Purpose

These lipid-based microspheres facilitate skin deposition and slow release. For example, SalSphere® with Salicylic Acid (BHA) is used effectively to suspend Salicylic Acid in water and for skin exfoliation, even for sensitive skin, reduction of excess sebum,  and delivering antiseptic properties.  Spheres with relatively smaller particles can enhance the efficacy of encapsulated active ingredients by reaching the lower layers of the epidermis, where they are needed the most.

Overall, SalSphere® allows slow release and reduces the impact of applying all the payload at once on the skin.

Structure

Micro suspension of solid spheres, structured with a core and a shell. The core is solid and made of a hydrophobic blend of materials, and a hydrophilic coating surrounds the core. The core functions as a reservoir for the encapsulated active. The spheres are suspended in water to form a homogeneous suspension.

The hydrophobic core is typically made of natural ingredients, such as waxes and lipids. The core composition varies from product to product; it’s optimized to offer high compatibility between the core and active, optimal payload, and meet the required release characteristics.  

The hydrophilic shell prompts the suspension of the SalSphere® microspheres in water.  The charge of the shell may be cationic or non-ionic. The hydrophobic properties of the core, combined with cationic surface charge, can further enhance the adhesion of the microspheres to skin or hair.

Mechanism

Three main conditions can trigger the release of actives from SalSpheres® (video). 

1. Gentle rubbing of the skin.
   The lipid core can dissolve into the skin's lipid domains and slowly discharges the load.
2. Heat.
   Exposure of the spheres to an external heat source, typically at a temperature above the spheres’ melting point (i.e., hair styling and drying equipment, such as air blower, curling, and ironing), can melt the core and trigger the release.   It's possible to design and manufacture a system to trigger the release at a predetermined temperature.
3. Skin proteolytic enzymes.
   In certain cases (i.e., Acne), there is an elevated activity of endogenous proteolytic enzymes, such as protease, lipase, etc. The activity of these enzymes is a natural response in case of inflammation.  These enzymes can trigger the release of active therapeutic from SalSphere® microspheres at the location (i.e., inflamed pimples), resulting in localized release.  The proteolytic enzymes can digest the core, made with lipids and proteins, and cause erosion of the core while releasing the payload.

Examples of Applications

1. Enable formulation.  
   SalSphere® encapsulation is a technique used in skincare and cosmetic formulations to enable the effective delivery of insoluble or poorly soluble active ingredients into the skin. Insoluble ingredients do not easily dissolve in water or other solvents. Encapsulation helps improve the stability, bioavailability and targeted delivery of these ingredients.   
   
   SalSphere® can help overcome compatibility issues that insoluble actives might have with the base formulation. Formulators can create a stable and uniform product by encapsulating the active ingredient without worrying about potential ingredient separation or inconsistencies.
2. Reduce irritation by slow, time-release.
   SalSphere® microspheres are designed to release their contents at specific locations within the skin. This targeted delivery can help ensure that the active ingredient reaches the layers most needed for its intended effect, such as stimulating collagen production or addressing inflammation. Many consumers have sensitive skin and thus can’t use traditional but effective exfoliating agents, such as Acids (i.e., AHA, BHA).  SalSphere® technology allows treating the skin with the full dosage but releasing it in small doses over a longer time. The slow release enables the skin to buffer the acid and reduce the signs of irritation. 
3. Accelerate anti-aging processes.
   The penetration of active ingredients into the skin is effective for anti-aging due to several reasons related to the physiological processes of the skin and the mechanisms of these active ingredients.
   The key factors:
   
   1. Targeting the Source of Aging: Active ingredients in anti-aging products are formulated to address specific causes of aging, such as collagen breakdown, oxidative stress, and reduced cell turnover. For these ingredients to work effectively, they need to penetrate the outermost layer of the skin (epidermis) and reach the deeper layers (dermis) where these aging processes occur.
   2. Stimulation of Collagen Production: Many anti-aging ingredients, like retinoids and peptides, stimulate collagen production. Collagen is a structural protein that provides firmness and elasticity to the skin. These ingredients need to reach the dermal layer, where collagen synthesis takes place.
   3. Repairing DNA and Cellular Damage: Some active ingredients, such as antioxidants (e.g., vitamin C, vitamin E), help protect the skin from free radicals and oxidative stress that damage DNA and cellular structures. These antioxidants must penetrate the skin to neutralize harmful molecules deep within the skin layers.
   4. Enhancing Cell Turnover: Active ingredients like alpha hydroxy acids (AHAs) promote the turnover of new, healthy cells. For these ingredients to work effectively, they must penetrate the skin and reach the basal layer, where new cells are formed.
   5. Moisturization and Barrier Repair: Ceramides are often used in anti-aging products to improve skin hydration and strengthen the skin's barrier function. These ingredients must penetrate the skin's outer layer to provide moisture and support barrier repair.
   6. Reducing Inflammation: Some active ingredients have anti-inflammatory properties that can help soothe irritated skin and reduce redness associated with aging. These ingredients need to reach the inflamed areas in the deeper skin layers.