J. Cosmet. Sci., 54, 113-118 (March/April 2003)
Potentiometric/turbidometric titration of antiperspirant
actives
CLIFFORD T. JOHNSTON, STANLEY L. HEM, ERIC GUENIN, JAIRAJH
MATTAI, and JOHN AFFLITO, Departments of Agronomy (C.T.J.) and
Industrial and Physical Pharmacy (S.L.H.), Purdue University,
West Lafayette, IN 47907, and Colgate-Palmolive Company, Piscataway,
NJ 08854 (E.G., J.M., J.A.).
Accepted for publication August 19, 2002.
Synopsis
A titration procedure that simultaneously monitors the pH and
turbidity of an antiperspirant solution during neutralization
with sodium hydroxide was developed to characterize antiperspirant
actives. Aluminum chloride, aluminum chlorohydrate (ACH), and
aluminum zirconium glycine complex (AZG) gave distinctive pH/turbidity
profiles. The activated forms of aluminum chlorohydrate (ACH_)
and aluminum zirconium glycine complex (AZG_) produced more
turbidity than the non-activated forms. On an equimolar basis,
AZG_ produced more turbidity than any of the antiperspirant
actives tested. 113
J. Cosmet. Sci., 54, 119-131 (March/April 2003)
Penetration studies of vitamin E acetate applied
from cosmetic formulations to the stratum corneum of an in vitro
model using quantification by tape stripping, UV spectroscopy,
and HPLC
P. LAMPEN, W. PITTERMANN, H. M. HEISE, M. SCHMITT, H. JUNGMANN,
and M. KIETZMANN, Institute of Spectrochemistry and Applied
Spectroscopy, D-44013 Dortmund (P.L., H.M.H.), Henkel KGaA,
D-40191 Du¨sseldorf (W.P., M.S.), MBR Messtechnik GmbH, D-45896
Gelsenkirchen (H.J.), and Institute for Pharmacology, Toxicology
and Pharmacy, Veterinary School Hannover, D-30559 Hannover (M.K.),
Germany.
Accepted for publication September 6, 2002. Presented in
part at the Conference on Stratum Corneum III, Basel, Switzerland,
September 12-14, 2001, and in Proceedings of the Conference
Stratum Corneum, R. Marks, J.-C. Le´veˆque, and R. Voegeli,
Eds. (Martin Dunitz Ltd., London, 2002).
Synopsis
The skin activation and penetration capability of vitamin
E acetate as an ingredient in a basic o/w cream (lamellar type),
in liposomes (Rovisome_) and microparticles (Roviparts_), was
investigated under in vitro conditions (BUS model) by the adhesive
stripping method. The aim of the study was to compare the analytical
results obtained by UV spectroscopy (transmission) and the conventional
HPLC method. For the quantitative spectrometric assay, a classical
least-squares evaluation of the spectra between 265 and 350
nm, based on the constituent spectra, was used. UV spectroscopy
is an economic analytical method for evaluating a large population
of samples of the horny layer taken by the adhesive tape stripping
method, which is an established tool for depth profiling of
substances within the stratum corneum. With regard to the irritation
test, no cytotoxicity was recorded for all formulations tested.
However, the Roviparts_ and Rovisome_ cream formulations induced
a considerable activation of the epidermal cells that may contribute
to the penetration efficiency of Rovisome_-formulated vitamin
E acetate. The Rovisome_- formulated cream delivered a maximum
amount of vitamin E acetate into the horny layer compared to
the other formulations tested. The difference can be explained
by an alteration of the plasticity of the horny layer inducing
a strong reservoir capacity and an activation of upper epidermal
cells. Moreover, the opening of the potential pathway for a
follicular penetration may be part of the increased reservoir
capacity. 119
J. Cosmet. Sci., 54, 133-142 (March/April 2003)
Inhibitory effects of Ramulus mori extracts
on melanogenesis
KANG TAE LEE, KWANG SIK LEE, JI HEAN JEONG, BYOUNG KEE JO,
MOON YOUNG HEO, and HYUN PYO KIM, Coreana Cosmetics Co., 204-1
JeongchonRi, Senggeoeup, Cheonansi, 330-830 (K.T.L., K.S.L.,
J.H.J., B.K.J.), and College of Pharmacy, Kangwon National University,
200-701 (M.Y.H., H.P.K.), Korea
Accepted for publication December 18, 2002.
Synopsis
To develop an active agent for skin whitening, the inhibitory
effects of 285 plant extracts on tyrosinase activity were examined,
and one plant extract having tyrosinase inhibition activity
was chosen. Ramulus mori (young twigs of Morus alba L.) extracts
showed inhibition activity in tyrosinase and melanin synthesis
in B-16 melanoma cells. To clarify the mechanism of its inhibition
on melanogenesis, the effect of R. mori extracts on tyrosinase
activity, synthesis, and gene expression was evaluated. R. mori
extracts showed tyrosinase inhibition activity by competitive
method, and there was no suppression of tyrosinase synthesis
and gene expression. Further, to evaluate the inhibitory activity
of R. mori in vivo, its effect on melanin production in UV-induced
brown guinea pigs was examined, where a decrease of melanin
production in the guinea pig model was observed. Also, R. mori
extracts showed no toxicity in animal tests such as the acute
toxicity test, the skin irritation test, the eye irritation
test, the skin sensitization test, and the acute oral toxicity
test, and no toxicity in the human skin irritation test. A single
compound from R. mori extracts was purified using various column
chromatography and recrystallization, and its chemical structure
was identifed using mass chromatography, IR spectroscopy, and
NMR analysis. The chemical structure was that of 2,3_,4,5_-tetrahydroxystilbene(2-oxyresveratrol)
and showed inhibition activity on tyrosinase (IC50 = 0.23 µg/ml).
Also, R. mori extracts inhibited tyrosinase activity in a competitive
manner (Ki = 1.5 × 10-6 M) when L-tyrosine was used as a substrate.
133
J. Cosmet. Sci., 54, 143-159 (March/April 2003)
Penetration of mixed micelles into the epidermis:
Effect of mixing sodium dodecyl sulfate with dodecyl hexa(ethylene
oxide)
PETER N. MOORE, ANAT SHILOACH, SUDHAKAR PUVVADA, and DANIEL
BLANKSCHTEIN, Department of Chemical Engineering, Massachusetts
Institute of Technology, Cambridge, MA 02139 (P.N.M., D.B.)
and Unilever Home and Personal Care NA, Trumbull, CT 06611 (A.S.,
S.P.).
Accepted for publication November 15, 2002.
Synopsis
The penetration of the anionic surfactant sodium dodecyl sulfate
(SDS) into the epidermis from contacting solutions of SDS and
the nonionic surfactant dodecyl hexa(ethylene oxide) (C12E6)
was measured for three SDS concentrations (25 mM, 50 mM, and
100 mM) and three SDS solution compositions (1, 0.83, and 0.50).
The addition of C12E6
to the SDS solutions was found to decrease the amount of SDS
penetrating into the epidermis. The observed decrease occurred
via two plausible mechanisms: (i) the addition of C12E6
decreased the SDS monomer concentration, thus reducing the driving
force for the penetration of monomeric SDS into the epidermis,
and (ii) the addition of C12E6
reduced, or prevented, the penetration of micellar SDS into
the epidermis. Using dynamic light scattering, the hydrodynamic
radii of the SDS/C12E6
micelles were determined to be 20 Å, for the _m = 1 micelles,
24 Å for the _m = 0.83 micelles, and 27 Å for the _m = 0.50
micelles (where _m denotes the SDS micelle composition). A comparison
with typical stratum corneum aqueous pore radii reported in
the literature (10-28 Å) suggests that the _m = 1 (pure SDS)
micelles are able to penetrate into the epidermis, while the
_m = 0.83 and the _m = 0.50 SDS/C12E6
mixed micelles are sterically hindered from doing so due to
their larger sizes. The observed reduced penetration of SDS
into the epidermis upon the addition of C12E6
could lead to a reduction in the skin irritation potential of
SDS, provided that there is a relationship between the concentration
of SDS in the epidermis and the skin irritation induced by SDS.
143
J. Cosmet. Sci., 54, 161-174 (March/April 2003)
Effect of formulation on the topical delivery
of _-tocopherol
MEERA RANGARAJAN and JOEL L. ZATZ, Organon USA, 375 Mt. Pleasant
Avenue, West Orange, NJ 07052 (M.R.), and Laboratory of Cancer
Research, Rutgers University, 41-D Gordon Road, Piscataway,
NJ 08854 (J.L.Z.).
Accepted for publication August 19, 2002.
Synopsis
The objective of this research was to investigate the effect
of concentration and delivery system on skin permeation of _-tocopherol
(_-T). Also, the addition of sunscreens and oleic acid on _-T
permeation was studied using an in vitro micro-Yucatan pig skin
model. Various delivery systems of _-T (1%) were formulated,
which included simple solution, gels, emulsions, and microemulsions.
The experimental design chosen for this study was a statistical
randomized complete block design. _-T delivery was proportional
to its concentration. The hydroalcoholic gel delivered significantly
higher amounts of _-T into the receptor than the other gels
used. A microemulsion containing isopropyl myristate emerged
as the best delivery system for _-T among all the systems studied.
Pig skin is a suitable in vitro model for studying the permeation
of _-T and possibly other antioxidants, though in vivo experiments
in humans are required to further corroborate the data. 161
J. Cosmet. Sci., 54, 175-192 (March/April 2003)
Effect of mineral oil, sunflower oil, and coconut
oil on prevention of hair damage
AARTI S. RELE and R. B. MOHILE, Research and Development Department,
Nature Care Division, Marico Industries Ltd., Mumbai, India.
Accepted for publication April 29, 2002.
Synopsis
Previously published results showed that both in vitro and
in vivo coconut oil (CNO) treatments prevented combing damage
of various hair types. Using the same methodology, an attempt
was made to study the properties of mineral oil and sunflower
oil on hair. Mineral oil (MO) was selected because it is extensively
used in hair oil formulations in India, because it is non-greasy
in nature, and because it is cheaper than vegetable oils like
coconut and sunflower oils. The study was extended to sunflower
oil (SFO) because it is the second most utilized base oil in
the hair oil industry on account of its non-freezing property
and its odorlessness at ambient temperature. As the aim was
to cover different treatments, and the effect of these treatments
on various hair types using the above oils, the number of experiments
to be conducted was a very high number and a technique termed
as the Taguchi Design of Experimentation was used. The findings
clearly indicate the strong impact that coconut oil application
has to hair as compared to application of both sunflower and
mineral oils. Among three oils, coconut oil was the only oil
found to reduce the protein loss remarkably for both undamaged
and damaged hair when used as a pre-wash and post-wash grooming
product. Both sunflower and mineral oils do not help at all
in reducing the protein loss from hair. This difference in results
could arise from the composition of each of these oils. Coconut
oil, being a triglyceride of lauric acid (principal fatty acid),
has a high affinity for hair proteins and, because of its low
molecular weight and straight linear chain, is able to penetrate
inside the hair shaft. Mineral oil, being a hydrocarbon, has
no affinity for proteins and therefore is not able to penetrate
and yield better results. In the case of sunflower oil, although
it is a triglyceride of linoleic acid, because of its bulky
structure due to the presence of double bonds, it does not penetrate
the fiber, consequently resulting in no favorable impact on
protein loss. 175
J. Cosmet. Sci., 54, 193-205 (March/April 2003)
Beyond rheology modification: Hydrophilically
modified silicone elastomers provide new benefits
MICHAEL S. STARCH, JEAN E. FIORI, and ZUCHEN LIN, Dow Corning
Corporation, P.O. Box 994, Midland, MI 48686-0994.
Accepted for publication July 24, 2002. Presented at the
Annual Scientific Meeting of the Society of Cosmetic Chemists,
New York, December 7-8, 2000.
Synopsis
The development of silicone elastomers with hydrophilic functionality
in the form of PEG substituents provides benefits beyond the
rheology modification (thickening) that can be achieved with
silicone elastomers that lack functional substituents. We have
shown that PEG-modified dimethicone crosspolymer (PEG-DCP) is
an effective emulsifier for water-in-silicone (w/s) emulsions
where the continuous phase is cyclopentasiloxane. The utility
of PEG-DCP for producing simple antiperspirant gels and also
multiple emulsions (w/s/w) was demonstrated. Additional benefits
for PEG-DCP such as improved compatibility with polar organic
oils and reduced syneresis in anhydrous antiperspirants were
also shown to be associated with the addition of hydrophilic
groups to the silicone elastomer. The performance and physical
properties of a series of PEG-DCP samples from a two-level factorial
design were evaluated. The variables studied were the level
of PEG substitution, the length of the PEG chains, and crosslink
density. All of the PEG-DCP samples were synthesized and tested
in the form of dispersions in cyclopentasiloxane. Variations
in the composition of PEG-DCP such as the level of PEG substitution
and the length of the PEG chain were shown to have a significant
effect on the viscosity of the PEG-DCP and its emulsification
performance in a simple w/s emulsion. Variation of a process
parameter that affects the crosslink density of the elastomer
also changed the emulsification properties of the PEG-DCP. 193
J. Cosmet. Sci., 54, 207-227 (March/Arpil 2003)
Papers Presented at the 2002 Annual Scientific
Meeting and Technology Showcase (Friday's Program)
December 5-6, 2002 New York Hilton New York, NY 207
BACK