Page 532 - Book Hosokawa Nanoparticle Technology Handbook

APPLICATIONS 21 DEVELOPMENT OF FUNCTIONAL SKINCARE COSMETICS

Epidermis

Without VC-IP loaded PLGA NS
administration
UV-A irradiation at 200J/cm 2 Non irradiation
Epidermis

Without
administration VC-IP loaded PLGA NS
UV-B irradiation at 2J/cm 2 Non irradiation
(Evaluation : Prefectural University of Hiroshima/Miwa lab.)
Human skin biopsies : Ear of 47-year-old woman
Figure 21.4
Effect of VC-IP loaded PLGA nanospheres on DNA double strand under UV irradiation.

areas were the damaged DNA strands. The skin sam- (NanoCrysphere) on the melanin production. These
ples treated with the VC-IP encapsulated PLGA human melanin-producing cells as shown in Fig. 21.5a
nanospheres closely resembled the un-irradiated skin can produce more melanin if treated with theophylline
samples. This demonstrated that the VC-IP encapsu- (a caffeine-like substance found in tea leaves). After
lated PLGA nanospheres have effectively reduced the being treated with theophylline, the cells turned to
DNA breakage due to the antioxidation effect of the have brownish-black color as shown in Fig. 21.5b,
reduced vitamin C, efficiently delivered and protected which confirmed the production of melanin. To
by the PLGA nanospheres. explore its effect on the melanin production, the func-
tional beauty essence (0.1 l/ml) was applied to the
3. Functional cosmetics using PLGA nanospheres cells 4 h before the theophylline treatment. Fig. 21.5c
shows that the functional beauty essence suppressed
As stated previously, because we were able to verify the melanin production that could have increased due
the benefits of applying vitamin encapsulated PLGA to the theophylline treatment. This result was attrib-
nanospheres, we developed skincare products mani- uted to the sustained release of vitamins encapsulated
festing skin whitening and anti-aging capabilities as PLGA nanospheres in the beauty essence.
shown in Figs. 21.5 and 21.6 (Hosokawa Micron
Cosmetics and NanoCrysphere Prime Serum (func- (2) Anti-aging effect of functional cosmetics
tional beauty essence)). PLGA nanospheres in these It takes more than several decades to develop wrinkles
products encapsulate, in addition to VC-IP, vitamin E on the skin. Therefore, it is not easy to evaluate the effi-
derivative (tocopherol acetate) and vitamin A deriva- cacy of wrinkle prevention agents in a short time for
tive (retinyl palmitate). They are mixed with beauty new product development. However, using the high-
essence at the time of use. Applying our proprietary speed artificial wrinkle formation system developed by
manufacturing process, the encapsulated PLGA Miwa et al., accelerated test results can be obtained.
nanospheres are compounded with water-soluble vita- The wrinkle formation system intermittently irradi-
min C derivatives and sugar alcohol to form nanocom- ates human skin biopsies with a critical dose of UV
posite powder with improved storage stability and rays while keeping the skin cells alive. By this way,
redispersibility in beauty essence. The efficacy of artificial wrinkles can be formed in a short time to
these products were evaluated and described below. evaluate the efficacy of wrinkle prevention agents.
Fig. 21.6 showed skin samples and their wrinkle-line
(1) Whitening effect of functional cosmetics [4] histograms. The skin samples were prepared by
We used human HMV-II melanin-producing cells to evenly dividing a human skin biopsy (from the ear of a
evaluate the effect of functional beauty essence 55-year-old woman), cultured in a modified Bronaugh

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