Do you care about deep penetration? Your skin does.
That’s why Costhetics is excited about innovations in transdermal drug delivery systems. TDS allow dermal therapists to treat ageing skin in a different way. Devices and techniques have been created to send skin-healing ingredients beneath the surface, past the stratum corneum layer to the dermis and subcutaneous connective tissue layers beneath.
A recent action by the TGA regarding microneedling has brought TDS into the spotlight. Don’t let the negative publicity scare you off the subject of TDS. They’ve been around for a long time and have lots of research that support their use.
Here’s what you need to know…
You Can’t Treat What You Can’t Reach
Several factors can affect how well an ingredient penetrates your skin:
- The area of the body where the ingredient is applied (some areas of the skin are extra thick)
- The concentration of an ingredient in a formulation (the higher the concentration, the more will be absorbed)
- Skin hydration level
- Molecular size of the ingredient
- The water-solubility of the molecules within the ingredient
It’s all about the stratum corneum (SC) the outermost layer of your skin. Its primary function is to protect your health by keeping bacteria, fungi, chemicals, and other bad things from getting into your system. Unfortunately, it is also a barrier to good things, like certain skin care product ingredients.
- Topical skincare products have active ingredients designed to sit on top of the skin. They are effective for moisturising and protecting skin but have no power to penetrate the stratum corneum.
- Transdermal active ingredients have the power to penetrate the skin’s surface to impact living tissue and skin cells at a deeper level, resulting in improved benefits and longer lasting results.
“In a nutshell, just because a performance ingredient is in a formula does not guarantee it will penetrate the skin in any quantifiable amount to deliver the claimed benefits,” says Dr Shyam Gupta, PhD, author of the paper Topical Delivery of Skin Care Ingredients.
Should You Go Active or Passive for Skin Beauty
A variety of devices are used to defeat the protective powers of the stratum corneum. In the article Pharmaceutical Developments Based on Disruption of the Barrier Properties of the Stratum Corneum, study authors describe the various ways to achieve TDD, broken into two categories: active and passive.
Active methods involve the use of external energy to disrupt the stratum corneum in a safe way that facilitates treatment without harming surrounding skin. Techniques and devices include:
Thermal ablation – these non-invasive techniques use heat to increase skin permeability by removing small portions of the stratum corneum
Electric – these methods use short, high voltage non-thermal pulses to promote desquamation (the skin’s natural exfoliating process)
Mechanical – tiny needles delivered in a treatment called microneeding create micron-sized pathways to deliver healing ingredients directly to the epidermis or upper dermis where they can then directly go into the systemic circulation
- Dermal Injector – produces a focused stream that penetrates the stratum corneum to deliver medication into targeted skin tissues without needles.
Passive methods also modify the stratum corneum structure. They do so chemically, rather than physically:
- Optimisation of formulas
- Chemical enhancers
- Eutectic systems (used to reduce the melting point of an ingredient)
- Prodrugs (use to enhance delivery by reducing crystallisation, increasing skin partitioning and aqueous solubility)
Australia Goes Transdermal to Treat Acne Dots
The TDDS sector is growing and evolving. Recently, an Australian skin care company began using needles in a new way to achieve transdermal delivery of its ingredients. It has created a pimple-fighting hydrocolloid sticker patch with 24 micro-darts on its surface. The micro-darts dissolve over a two-hour period to “flood the epicentre of your early-stage zit with targeted ingredients” says their website. The idea is to disinfect and kill the pimple before it reaches the surface.
The manufacturer notes that only certain ingredients can be delivered via patch. For example, the company has avoided using traditional acne-fighting ingredient benzoyl peroxide. Though fine for topical use, benzoyl peroxide is irritating when used at a deeper skin level, leading the company to choose a peptide alternative.
The Future is Trans
The aesthetics industry is constantly focused on improving patient convenience and comfort. To meet their needs, pharmaceutical and medical device companies are continuously working to develop new devices that are:
- Side-effect free
Those are Costhetics three favourite words whenever we talk about healthy beauty. Make them yours, too, okay? Listen for them when you talk to your skin care therapist to keep yourself gorgeous…and safe!