1. Surfactants & Formulations
Physical Pharmacy 2
4/1/2017
Surfactants & Formulations
Kausar Ahmad
Kulliyyah of Pharmacy, IIUM
Physical Pharmacy 2
KBA

2. Choice of surfactants HLB PIT H/L numbering Water absorbing method
Applicable for simple phase emulsions but not for complex phase materials.
Normally based on trial and error
Physical Pharmacy 2

3. Characteristics of Emulsifiers
Combination of anionic and nonionic to give excellent emulsion stability and viscosity control
Examples of nonionic fatty acid monoglycerides, sorbitan fatty acid esters, sugar esters, derivatives of polyoxyethylene fatty alcohol ethers/fatty acid esters/sorbitan fatty acid esters/hydrogenated castor oil
Examples of anionic fatty acid soaps, fatty alcohol sulfates
Physical Pharmacy 2

4. Fatty acid monoglycerides w/o vanishing creams/lotions
Surfactants
Application
Advantages
Fatty acid monoglycerides
w/o vanishing creams/lotions
Not sticky, excellent thickening
Sugar esters
Cosmetic formulation
Not efficient but complete safety
POE fatty acid esters & hydrophobic
Creams & milky
lotions
Great thickening BUT hydrolysis
Fatty acid soaps & nonionic
creams
Excellent chemical stability, gloss and viscosity BUT alkaline
Alkyl sulfate
& nonionic
Low foaming BUT skin irritation
Physical Pharmacy 2

5. Surfactants in Cosmetics
Determine appearance, chemical & physical properties, usage and storage conditions
From soaps changed to nonionic surfactants – less toxic
Emulsifiers should satisfy the following:
No toxicity and skin irritation
Chemically and physically stable (expiry?)
Surfactants should not affect other ingredients – too many ingredients!
Physical Pharmacy 2

6. Formulation Examples of Creams and Ointments
O/W COLD CREAM
Stearic acid
Liquid paraffin
Vaseline
Cetyl stearyl alcohol
POE polyol f.a. esters
Glycerine
TEA
Deionised water
Methyl paraben
perfume
Physical Pharmacy 2

7. Cosmetic Bases Fats and oils Waxes Hydrocarbons Fatty acids Alcohols
esters
Requirement
Low toxicity and skin irritation
No harmful effect on dermo-physiology
Physical and chemical stability
No propagation of bacteria
Physical Pharmacy 2

8. Shampoos Surfactants Anionic POE alkyl ether sulfate
Amphoteric imidazoline (low iritant)
nonionic fatty acid alkalonamides
Requirement
Satisfactory cleansing power
Easy rinsing – no scum
Soft & good manageability
Luster
Low irritation to skin & eyes
Physical Pharmacy 2

9. Additives for Shampoo Preservatives benzoic/salicylic acid
Thickening agents cellulose
Anti-oxidant BHT
Ultraviolet rays absorbent benzophenone
Conditioning agent fats/oils, cationic surfactant
Anti-dandruff agent selenium disulfide
Opacifier mica, polystyrene
Physical Pharmacy 2

10. Example of Shampoo Formulation
Refer YOUR actual shampoo formulation!
Physical Pharmacy 2

11. Cream Rinse and Conditioner
Primary ingredient is cationic surfactant ca. 1-5% e.g. dialkyl dimethyl ammonium salt; the longer the alkyl chain, the greater the softening effect (thick conditioner?)
E.g. of nonionic POE sorbitan fatty acid ester
Physical Pharmacy 2

12. Ingredients other than surfactants
Fats & oils
Solvent and humectant
Thickener
Physical Pharmacy 2

13. Dentrifices
Pastes blended suspension of liquid paste thickened with binders
Gels
Powders
Liquids
Physical Pharmacy 2

14. Ingredients and Composition of Toothpaste
Polishing agents: sodium metaphosphate
25-60
Humectants: glycerine
10-30
Foaming agent: sodium alkyl sulfate
0.5-2
Binder: carrageenan
Flavour: peppermint
0.5-3
Sweetener: sodium saccharine
0.1-1
Preservative
Therapeutic agent: neem, gamat?
water
To 100%
Physical Pharmacy 2

15. Surfactants in Toothpaste
Provide the expected foaming
Reduce surface tension
Penetrate and loosen surface deposits
Emulsify and suspend debris which toothpaste removes from surface of teeth
E.g sodium lauryl sulfate, sodium coconut monoglyceride sulfonate
Physical Pharmacy 2

16. Exercise Identify surfactants in What are their specific functions?
Hair shampoo
Mouth wash
What are their specific functions?
Physical Pharmacy 2