How to formulate customisable skincare

Customisable skincare step 1: Formulate the base creams

Cosmetic brands can create customisable skincare for a very targeted market with one base cream formula; however, if your brand wants to broaden its scope and accommodate a larger target market, then you will typically need two base creams:

• Light base cream: ideal for younger, oilier skin types or Asian skin types, the light base cream will have a medium lipid input using light skin feel esters or silicones with only a touch of natural plant oils if desired. This product should feel instantly light to apply to suit these skin types.
• Rich base cream: created for dry, sensitive and mature age skin types, the rich base cream should be a much richer base formula with more lipids, medium-heavy skin feel esters, triglycerides and some plant oils to support a natural product story. It should have a lasting emolliency on the skin to suit those in need of more hydration.

Each base cream must also include essential stabilising ingredients that will accommodate a variety of active ingredient additions later, so they must not be affected electrolytes or extreme pH; and they must accommodate additions of liquid concentrates. This means making careful selections with:

• gums or polymers: essential to help ensure homogenous mixing of the active concentrates, gums or polymers chosen must be electrolyte tolerant and must readily mix with any additives. It is ideal if you can find a suitable gum/polymer with neutral charge, or at least one that is not impacted by the addition of charge.
• use non-ionic emulsifiers only: using emulsifiers that carry charge will leave your base cream at risk of electrolyte sensitivity and destabilisation. Choosing non-ionic emulsifiers also increases the mildness of your finished product.
• use non-oxidising lipids: lipid selection is crucial to suit the skin type of the user and whether it be the light or rich base cream. In addition, the more stable the lipids, the less oxidation risk your base cream formula has over time once actives are added. Plant oils can make a great addition to formulas for their fatty acid profiles and product story, but keep their input low so that they don’t impact stability of your base creams unnecessarily.  
• the preservative: choose a preservative that is compatible over a broad pH range so that it will suit the addition of various active concentrates. The preservative you choose should also be effective in the presence of various charge, strong in the presence of non-ionic emulsifiers (since that is what you will be using) and have minimal incompatibilities.
• antioxidant: mixed tocopherols will help provide antioxidant protection to the base formula as well as the skin; they make a great addition to your base cream no matter how it is formulated or what you will be adding in the active concentrates.

Customisable skincare step 2: Formulate the active concentrate

Your active concentrates should contain 1-2 key actives that address specific consumer wants and needs. As well as choosing the actives you want to use, you will also need to choose the packaging that holds the active concentrate, as it either needs to be extremely small for daily mixing, dispense in discrete quantities for daily mixing, or suit addition to the base cream jar for once-off mixing.

Once you have selected your actives and the packaging you will use for the actives, you can then determine the strength needed to suit the individual application, or final jar packaging. For example, if the efficacy data for your chosen active needs to be used in a face cream at 5% twice daily, you will need to make sure your dosage applicator from the concentrate enables a consumer to measure out what they need to mix with the base cream quickly and easily for daily use; or that your finished product jar will accommodate the addition of your active concentrate with room to be mixed. Remember essential rules for claims and evidence, when selecting your actives – watch this video.

Finally, it is a great idea to include some stable herbal extracts in your active concentrate that pair nicely with the key actives (if they are not a blend of herbal extracts themselves) to give a unique product story to your concentrate. If you are adding herbal extracts to boost consumer appeal and marketing story, choose stable extracts in a glycerin base for easy addition.

Here are some tips for addition, for example, where an active is needed at:

• 2%w/w in a finished product: 1%w/w of this active is needed per 50 grams (g) of base cream. A 10g serum containing 1g of active concentrate could be mixed into 40g of base cream in this example. The remaining 9g of serum could be a mixture of propanediol, glycerin-based extracts or another water-soluble active as desired.
• 5%w/w in a finished product: 2.5%w/w of this active is needed per 50g of base cream. Again, try to standardise your serum concentrates; in which case you would need 2.5g of active in a 10g package to be mixed with 40g of base cream. The remaining 7.5g could be a mixture of glycerin, extracts or other water-soluble actives.

Remember: your active concentrate may not need a preservative. Where the active is provided in a humectant only base, send it for available water testing; if there is low available water (Aw<0.6), micro-organisms growth is inhibited and a preservative is not needed.
 

Customisable skincare step 3: Check regulations, safety and stability

When preparing and selling active concentrates, you will need to carefully check local country regulations because those rules apply to the active concentrate also. You may need to add special seals or labelling statements to comply with regulations when packed in the active concentrate form.

Careful labelling is essential anyway, since the active concentrates could cause significant skin issues if not dispensed and diluted correctly. Unfortunately, some consumers think more is best, so there is potential for misuse. Make sure your active concentrates are labelled with clear mixing directions to avoid overuse and irritation issues.

Remember to check the stability of your base creams carefully first! They need to be tested under accelerated conditions with extreme ingredient additions, to ensure they are robust and will suit all active concentrates when mixed. If an open neck jar, be especially prudent with your preservative selection to avoid issues of consumer contamination once actives are added and mixed. See how stability testing is conducted, watch this video.
 

Customisable skincare on trend

There is no doubt customisable skincare is on trend and growing in popularity. It helps a consumer feel empowered by their skincare choices and makes your brand appealing from a scientific and efficacy-based perspective when you can give them active concentrates that suit consumer needs and wants. Its also a great way to really appeal to key consumer demographics based on results-oriented skincare trends.

Just remember to formulate those base creams carefully, stability test well, and provide clear directions for mixing, matching and using the actives with the base to ensure the best possible results.
 

Happy formulating!