Colloid & Surface Phenomena
Loition
Jason Ashbery
Jonathan Danner
Haohao Huang
Leigh Vorreuter
I. Product Design Considerations
• Customer Needs
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Heals dry skin
Prevents dry skin
Non-greasy
Fast absorbing
Non-irritating
Non-scented or Scented
Contains sun screen
Prevent further aging of the skin
Long lasting
Product Design Considerations
• Different Types of Lotion
• For Dry Skin
• For Extra Dry Skin
• For Sensative Skin
• Manufacturers
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Bath & Body Works
Suave
Keri
Bristol Meyer Squibb
Clairol
Product Design Considerations
• Product Specifications
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Shelf life
Duration
Consistency
Viscous properties
Fragrance
Color
Absorption
Delivery systems of alpha hydroxide, sunscreen,
moisturizing agents
II.
Components and Composition
Common Components Present in Different Brands of Moisturing Lotion*
Suave
Bath & Body
Bristol
The Andrew
Works
Meyers
Jergens Co.
Body Benefits
Water
X
X
X
X
X
Glycerin
X
X
X
X
X
(Tetra, Tri, or Di-) sodium EDTA
X
X
X
Dimethicone
X
X
X
Carbomer
X
X
X
X
X
Tocopheryl Acetate (Vitamin E)
Aloe gel
X
X
Petrolatum
X
X
Glyceryl Stearate
X
Sodium Hydroxide
X
DM DM Hydantoin
X
Benzyl Alcohol
X
Propylparaben
X
Mineral Oil
X
X
X
X
X
X
X
X
X
X
X
Magnesium Aluminum Silicate
X
X
X
Methylparaben
X
X
X
X
Isopropyl palmitate
X
X
X
Cetyl Alcohol
X
X
Cetearyl Alcohol
X
X
Ceteareth-20
X
X
* Components present in only 1 of the 5 lotions are not listed here.
Approximate Composition of a Lotion Patented by
The Andrew Jergens Company (U.S. Patent# 6,017,548)
Chart #
Components
Approx. % Weight
1
Water
93.2
2
Glycerin
2.4
3
Dimethyl Distearyl Ammonium Chloride
4
Petrolatum
0.8
5
Lactic Acid
0.6
6
Isopropyl palmitate
0.6
7
Cetyl Alcohol
0.5
8
Glycolic Acid
0.4
9
Dimethicone
0.3
10
Ammonium Hydroxide
0.2
11
Methylparaben
0.02
12
Propylparaben
0.008
1
Approximate Percent Weights
1
2
3
4
5
6
7
8
9
10
11
12
III. Colloids and Surface
Interactions
• Functions of colloids in Moisturizing Lotion
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Diluent
Humectant
Smoothing aid
Emollient
Surfactant
KERI FRAGRANCE FREE LOTION
Component
Basic Function
Water
diluent
Glycerin
humectant
Dimethicone *
emollient, smoothing aid
Petrolatum *
occlusive emollient
Disodium EDTA
chelating agent
Carbomer *
thickening agent, emulsifying agent
Quaternium-15 *
cationic surfactant, cationic emulsifier
Cetyl Alcohol *
emollient, emulsion modifier, coupling agent
Tocopheryl Acetate (Vitamin E) *
nutrient
Steareth-2 *
emulsifier, wetting agent
Aloe gel
nutrient
Benzyl Alcohol
antimicrobial
Laureth-23 *
emulsifier, wetting agent
Magnesium Aluminum Silicate
thickening agent
Sodium Hydroxide
alkalizer, pH adjuster
* = "colloidal" sized molecules
Liquid/ Liquid Emulsion
• An emulsion is formed when a mixture of two
immiscible liquids are separated by a surfactant
molecule.
• Oil-in-Water (O/W)
• Water-in-Oil (W/O)
O/W and W/O Emulsion
Phase Inversion of Emulsion
• Inversion from W/O to O/W
• Variables which lead to phase inversion
• Temperature – Ethoxylate emulsifiers
• Surfactant composition – Hydrophilic emulsifier
concentration
• Water concentration – Andrew Jergens Co.
Effect of Amphiphiles on
Delivery to the Skin
• Cationic Surfactants
• Effect of Temperature and Salt on micelle stability
• Effect of Temperature on delivery
• Pemulen® Polymeric emulsifiers
• Triggered release mechanism upon contact with
electrical charge of skin
Traditional Surfactant Emulsion
Pemulen ® Polymeric Emulsifiers
IV. Product Attributes
• Shelf Life
– Emulsion stability is what determines the product’s
shelf like
– If the emulsion becomes unstable the lotion will
separate
– Adjusting the hyrophilic and lipophile balance of the
emulsifier achieves the emulsions stability
– The emulsions are thermodynamically unstable due to
its positive interfacial energy
– When the emulsion tries to reach it thermodynamic
equilibrium it causes the emulsion to break up back to
its component phase
Product Attributes
• Shelf Life
– The delay of the component break up can be
accomplished by adding specific mixed emulsions
compiled of non-ionic and ionic surfactants and
combined with fatty amphiphiles
• Examples can be found in Table 3
– Previously blended emulsifying wax into the the
formulation can also help prevent the decay of the
emulsions
• Examples can be found in Table 4
Product Attributes
Table 3
Fatty amphiphiles
Cetostearyl alcohol
Cetyl alcohol
Stearyl alcohol
Glyceryl monostearate
Stearic acid
Phosphatidylcholine
Surfactants
Sodium lauryl sulphate
Cetrimide
Cetomacrogol 1000
PEG 1000 monostearate
Triethanolamine stearate
Sodium stearate
Table 4
Emulsifying wax
Component
Emulsifying wax BP
Cetostearyl alcohol, sodium lauryl sulphate
Emulsifying wax USNF
Cetyl alcohol, polysorbate
Cationic emulsifying was BPC
Cetostearyl alcohol, cetrimide
Glyceryl monostearate S.E.
Glyceryl monostearate, sodium stearate
Cetomacrogol emulsifying wax BPC Cetostearyl alcohol, cetomacrogol 1000
Polawax
Cetyl alcohol, non-ionic surfactant
Product Attributes
• Shelf Life
– The gel network theory of emulsion stability is
why both emulsifiers and mixed wax help the
shelf life period
– The emulsifiers stabilize the oil droplets by the
formation of an interfacial film
Product Attributes
• Consistency
– It is related to swelling properties and concentration of
the α-crystalline gel phase
– When the α-crystalline form is in presence of very
small quantities of ionic surfactants and a fatty aclohol
and is dispersed in water the amount of swelling
increases
– This leads to the swelling of the α-crystalline gel phase
– The water is in between the bilayers of the gel phase
and when it swells the volume ratio of dispersed phase
to the free continuous phase water increases
Product Attributes
• Evaporation and Absorption
– When lotion is rubbed into the skin water
evaporates and the oil droplets coalesce
• Coalescence occurs when the interfacial energy
between substrates and adatoms is small
– The clusters can detach themselves from any given
location on the surface and diffuse as entities over the
surface
– The clusters behave more like liquid than solid crystallites
Product Attributes
• Evaporation and Absorption
– After the application of the lotion the
composition changes as the water and other
other volatiles solvents evaporate
– A film stays on the skin as a protector and the
nutrients are absorbed
– Absorption capacity increases with decreasing
viscosity
Product Attributes
• Viscosity
– Emulsion size and concentration determines the
viscous properties
– At the same shear stress and droplet
concentrations the viscosity of concentrated
emulsions containing smaller droplets was
significantly greater
– This suggests that electrostatic repulsion plays
an important role in determining the rheology
of concentrated emulsions
Product Attributes
• Viscosity
– The droplets become closely packed causing
the emulsions to be come rigid at lower
concentrations for smaller droplets because of
their effective volume fraction is greater
– This explains why low emulsifier
concentrations are good for structured lotions
– Lotions are not suppose to be very thick and
viscous
Product Attributes
• Fragrance
– Fragrances are applied by collodial systems like
emulsions
– The lipid part of the stratum corneum is organized in
lamellar structures
– The lamellar liquid crystals in lotions contain the
fragrance molecules
– The similarity of the configuration of the crystals in
lotion compared to the stratum corneum is why it easy
for the fragrance to be absorbed into the skin
– The location of the interlayer spacings and the
geometrical characteristics play a big role on where the
location of the fragrance is
Product Attributes
• Improvements made to the skin
– Liposomes have positive effects on the appearance of
the skin
– Improve cutaneous hydration, skin structure, depths of wrinkles
– Liposomes are spherical vesicles that have an aqueous
cavity at their center
– They are used to carry water-soluble molecules and
hydrophobic molecules
– Liposomes have been evaluated as delivery systems for
drugs, vitamins and cosmetic materials
Product Attributes
• Delivery Systems
– Particulate systems are very small particles that
range from micrometers to millimeter
– These particles deliver essential active
ingredients such as amino acids, plant extracts,
minerals, vitamins, antioxidants, and UV
protectants
– They also prolong the time during which the
ingredient remains on the skin
V. HAOHAO
VI. Manufacturing Process
• The objective is to disperse one liquid
within another in an extremely fine form to
make certain that separation due to settling
either does not occur or takes place very
slowly.
• Does not normally involve any extraction or
chemical reaction.
A Few Parameters that may influence
liquid-liquid emulsion formation
• Shear rate
• Sufficient stabilizers need to be present to
maintain the smallest droplet size produced for
long periods of time.
• Blend time and standard deviation of circulation
time.
• These along with many other parameters make it
difficult to specify a mixing process based on
desired droplet size. Most predictions are based
on existing data.
Pilot Scale Manufacturing Process (US Patent# 6,017,548)
Federal Rules and Regulations
• CGMP’s – Primary objective is to ensure that
manufacturers provide consumers with safe and
effective products.
• Parts 210 and 211 apply to manufacturing of drugs
and finished pharmaceuticals.
• Part 210 contains a basic overview and some
definitions that are used in Part 211.
Part 211
• Gives a description of responsibilities of the
quality control unit.
• States that proper training procedures must be in
place.
• Buildings and Facility requirements
• Cleaning requirements- Rooms and Equipment
• Proper labeling and storage of materials
• Batch Records
Marketing Considerations
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Packaging aesthetics
Fragrance
Color of Lotion
Shelf Location