One of the most common questions I receive is, “What is the best way to choose a product line for my skin?” It can be a complicated and expensive process, especially when faced with the hundreds of product lines available in the professional market.
This new column will address specific areas of cosmetic chemistry, along with questions you should ask when choosing a product line. You will also see definitions the US Food and Drug Administration (FDA) may use when looking at the difference between a cosmetic and a drug.
We’ll begin with delivery systems; this is the part of the formulation that makes the difference for a results-oriented product.
WHAT ARE COSMETIC DELIVERY SYSTEMS?
A cosmetic delivery system is designed to create a desired result within the skin by delivering active ingredients to a specific biological target. This can be anything from enhancing cell communication to direct delivery into a layer of skin. There are additional benefits of delivery systems beyond getting the ingredients past the stratum corneum; some delivery systems will help protect antioxidants from oxidation and discoloration.
Since there is an extensive number of proprietary systems, and each works differently within a formulation, it is important to understand the overall concept of delivery systems before getting technical with your manufacturer.
The best way to look at delivery systems is to identify the difference between the two categories: vehicles and encapsulation.
Vehicles
A vehicle is the formulation of the product that contains active ingredients. Some common vehicles are solutions, emulsions, gels, hydrolipid dispersions, and suspensions. These formulas can improve the skin as a whole or deliver actives that dissolve into the stratum corneum when applied to the skin.
Encapsulation
Encapsulation is the delivery form most estheticians are aware of. This category of delivery system is also commonly referred to as an ingredient carrier. You will recognize these carriers under some common names such as liposomes, microsponges, nanosomes, and nanospheres.
Generally, the inner part of the capsulation contains the active ingredients, while the outer portion either maintains stability and adheres to the skin surface or dissolves to release the active ingredients. The most popular systems use ingredients that mimic the skin’s lipids for best absorption within the skin. Liposomes are an example of this.
HOW DO ACTIVE INGREDIENTS WORK?
Understanding skin physiology and structure is essential; when you can identify the makeup of the skin’s acid mantle and lipid bilayers, you will see how an encapsulated delivery system begins to work within the epidermis.
Let’s take a look at how one of the most widely used delivery systems, liposomes, work within the skin.
- After the product is applied to the skin, the outer shell of the encapsulated carrier binds to the stratum corneum.
- The carrier begins to dissolve through the lipid bilayers; phospholipids are a main component of liposomes and are accepted by the skin’s bilayers, while the water portion of the formulation is delivered past the stratum corneum. 3. The active ingredients are released as the delivery system melts into the epidermis. These actives then can perform based on what they are and how they are designed to react on the skin.
The effectiveness of these delivery systems is based on the health of the skin barrier, concentration of the active ingredients, temperature of the skin, and overall composition of the formulation, including pH.
Beatrice Smith | becspink.com
It is also important to note that many of the benefits manufacturers cite about their active ingredients are dependent on reaching a live cell. This may or may not be possible, depending on the overall formulation.
Since many of the delivery systems used in cosmetics also have a role in drug delivery, cosmetic chemists must be careful to formulate a cosmetic that can not be classified by the FDA as a drug. This can be an issue if the marketing claims a product can affect the structure and function of the skin.
The term cosmeceutical is an example of an attempt to bridge the gap between cosmetics and drugs, but it is not a term that is recognized by the FDA. These cosmeceuticals are examples of advanced delivery systems.
In Summary:
- Delivery of active ingredients can be achieved by the overall formulation or encapsulated carriers such as liposomes.
- Manufacturer claims must be cosmetic in nature to avoid being classified as a drug by the FDA.
- Understanding skin structure and function is essential to understanding how formulas work. • It’s not just the ingredient that makes the difference in whether or not a product is effective—it’s the overall formula, delivery system, and how the product is used.
References:
- Abdullaeva, Z. (2017). Nanomaterials in Health care and Cosmetics. In Nanomaterials in Daily Life (pp. 47-65). Springer, Cham.
- Choi, C. M., & Berson, D. S. (2006, September). Cosmeceuticals. In Seminars in cutaneous medicine and surgery (Vol. 25, No. 3, pp. 163-168).
- Casanova, F., & Santos, L. (2016). Encapsulation of cosmetic active ingredients for topical application–a review. Journal of microencapsulation, 33(1), 1-17.
- Rosen, M. (2005). Delivery system handbook for personal care and cosmetic products: technology, applications and formulations. William Andrew.
- Weiner, N., Lieb, L., Niemiec, S., Ramachandran, C., Hu, Z., & Egbaria, K. (1994). Liposomes: a novel topical delivery system for pharmaceutical and cosmetic applications. Journal of drug targeting, 2(5), 405-410.
