• The laboratory for dermatological applications (LDA) is concerned with testing of developed cosmetic raw-materials at different levels and with utilisation of various experimental models. The most important are then in vivo safety testing of topical product applications, as well as testing of their protective and biological activity after the applications to the skin of human volunteers. The raw-material efficiencies are evaluated according to their ability to increase or decrease the activities of epidermal enzymes, to stimulate or inhibit the production of structural and signal proteins, and to influence the gene expressions of markers involved in the key biochemical processes. Finally, the harmony of partial results on molecular levels is verified by macroscopic skin parameter measurements such as hydration, colour, elasticity and wrinkle depth, as well as its barrier function.
• Furthermore, the laboratory develops the final cosmetic applications for our raw-materials including the stable typical formulations and technological recommendations, verifies the compatibilities of the final product components and provide our customers with the advisory servis.

Methods being used in the cosmetological laboratory

• In vivo evaluation of moisturising effect on stratum corneum (Corneometer CM 820, Courage+Khazaka)
• In vivo evaluation of sebum content on the skin surface (Sebumeter SM 810, Courage+Khazaka)
• Skin pH measurement (Skin-pH-meter PH 900, Courage+Khazaka)
• Evaluation of the skin elasticity (Cutometer SEM 474, Courage+Khazaka)
• Skin colour measurement, evaluation of erythema and melanin index (Spectrocam 75 RE, Spectrostar)
• In vivo evaluation of human skin barrier function, TEWL measurement (Dermalab, Cortex Technology)
• In vivo skin irritancy test
• Evaluation of the sodium hydroxide-extractable proteins in the epidermal material collected by the tape stripping method (D-Squame, CuDerm corp.)
• In vivo prevention of corneocyte desquamation after SDS treatment
• Evaluation of the enzyme activity (acid phosphatase, ?-glucocerebrosidase, ?-glucuronidase, esterase, phospholipase A2, catalase, trypsin, chymotrypsin) in the epidermal material collected by the tape stripping method (D-Squame, CuDerm corp.)
• IL-1?, IL-1?, IL-4, IL-6, IL-8, IL-10, IL-12, IL-16, IL-18, TNF-? evaluation in the epidermal material collected by the tape stripping method (ELISA)
• Digital photography (Nicon Coolpix 4500, Nicon )
• Evaluation of skin profilometry on human skin
• Evaluation of the in vitro protective effect on the OH radical-induced phospholipid peroxidation
• Evaluation of the in vitro protective effect on the UV-induced phospholipid peroxidation in the presence of titandioxide
• In vitro fluorimetric (DPPP) evaluation of hydroperoxides in the lipidic specimens
• In vitro spectrophotometric or fluorimetric evaluation of thiobarbituric acid reactive substances (TBARS) in the lipidic specimens
• In vitro DPPH quenching test
• Reduced glutathione (GSH) content evaluation in the epidermal material collected by the tape stripping method
• Oxidized glutathione (GSSG) content evaluation in the epidermal material collected by the tape stripping method
• Glutathione peroxidase, glutathione reductase activities evaluation in the biological specimens
• Evaluation of the lipid hydroperoxides on the skin surface after UVA irradiation in vivo
• Evaluation of the spontaneous hydrogen peroxide formation in the polyphenol solutions
• Evaluation of the in vitro protective effect on the AAPH-induced albumin carbonylation
• Evaluation of the in vitro protective effect on the UV-induced albumin carbonylation
• In vivo evaluation of SC turnover by the measurement of spectral reflectance of dihydroxyacetone-stained skin
• In vivo evaluation of non-labelled hyaluronic acid penetration into the stratum corneum by the tape stripping method
• In vivo evaluation of size distributions of corneocyte aggregates