1. Formulating for EfficacyTM
Copyright © 2014 ACT Solutions Corp. All rights reserved.

2. Why Formulate for Efficacy?
Actives are expensive
Claims substantiation is expensive
Advertising is expensive
Litigation is expensive
Getting new customers is expensive
Developing new products is expensive

3. Standard formulation design process
Clinical testing
Stable base
Concentration
Model activity
Intrinsic activity

4. How to increase skin delivery?
K = Partition coefficient (of active between formulation and skin)
The math bit…
D = Diffusion coefficient (of active into skin)
L= Path length (of active through skin)
Ficks’ 1st Law (~rate of active penetrating into skin):
J is from Ficks first law, for penetrant going through membrane. Two key things we can affect:
1) Initial concentration in formulation – flux is increased when this is increased
2) Partition coefficient K: in order to get active into skin, it must penetrate from formulation into stratum corneum, controlled by K, ratio of maximum solubilities. Therefore, the quantity of molecules penetrating into the stratum corneum can be increased by increasing the solubility of the penetrating molecule in the stratum corneum or by reducing its solubility in the formulation.
Rate of active penetrating into skin can be increased by maximizing the initial amount in the formulation

5. Categories of actives Insoluble Oil soluble/low polarity
Sparingly water soluble
Freely water soluble

6. Hansen solubility parameters
Solvency predictions
Dispersion forces
van der Waals forces
Polar forces
Dipolar intermolecular forces
Hydrogen bonding forces
Electromagnetic attractive interactions

7. Assessing other challenges to delivery posed by actives
Size
MolV (Molar Volume)
Difference in polarity with Stratum Corneum
ASG (Active Skin Gap)

8. Franz Diffusion Cell Data
3.5 fold increase 5 10 15
Formulation not
optimised for delivery
Delivery optimised
formulation
Dioic Acid Delivery ( μ
g/cm 2 )
Tapes
Stratum Corneum
Receptor fluid

9. Formulating for Efficacy™ Approach
Intrinsic activity
Model activity
Assess properties
Evaluate challenges
Design active phase for solubility and driving force

10. Dynamics of product on the skin
Application
Evaporation
Permeation

11. Impact of the Emulsifier
Stability (OK, that’s obvious)
Aesthetics (yes, but how much?)
Delivery (where does it fit with such approaches as Formulating for Efficacy™ ?)

12. Wiechers study shows that emulsifier selection controls:
74% of overall aesthetic quality of an emulsion
Nearly 100% of Appearance, Pick-up, and Rub-out characteristics
MESSAGE:
Change emulsifier to change aesthetics
Use emollient variation to adjust After-feel

13. Emulsion Stabilization Mechanisms
Steric
Charge
Pickering
Polymer
Liquid crystalline

14. Adaptive Approach to Aesthetic Design
Emulsifier
Appearance, Pick-up, Rub-out
Test with target audience
Emollient
Adjusting After-feel

15. Driving Development
Water, Polar Carriers and Humectants, Actives, Polymers
Emulsifiers
Emollients, Actives, Waxes

16. Enlightened Formulation Wheel
Actives
Emulsifiers
Polar carriers, humectants
Emollients
Fragrance
Preservative
Polymers and waxes

17. Further formulation design
Design emulsion for aesthetics
Design emulsion for delivery
Test with target audience
Clinical trials
Success !!

18. Contact information
Mark Chandler
President, ACT Solutions Corp
Research Instructor, Univ. of Toledo
Office:
Mobile:
550 S. College Ave., Suite 110
Newark, DE