LEARNING OUTCOMES
The aim of the course is to teach students the physicochemical methods used to evaluate the effectiveness of cosmetic products and their correlation with the proof of the claims made on cosmetic products.
The aim of the course is to acquaint students with the main biophysical methods used to evaluate the effectiveness of cosmetic products and to enable them to prepare protocols, conduct and evaluate effectiveness studies – claim substantiation according to international clinical practice and international guidelines.
Learning Outcomes:
After the end of the course students will be able to:
- know the basic principles of designing and conducting cosmetic efficacy studies in volunteers in accordance with the international clinical practice (GCP).
- know the basic principles of the methods (sensory and biophysical) used for the evaluation of the effectiveness of cosmetic products with emphasis on the evaluation studies of the skin protection from ultraviolet radiation and the intra / transdermal absorption studies.
- know the physicochemical methods for quantification of the biophysical parameters of the skin such as elasticity, hydration of stratum corneum, etc.
- Evaluate the results of effectiveness studies
- Compare the effectiveness of products that “carry” the same claim of action.
- Compare effectiveness evaluation methods for the same action
- Design, organize and conduct studies on the effectiveness of cosmetic products with sensory and biophysical methods, in vivo, in vitro and ex vivo in accordance with international good practice.
SYLLABUS
Theory
1. Effectiveness study assays-Study design and organization. Efficacy study writing. Proof of claims. Legislation to substantiate claims in the European Union. Sensorial and biophysical studies. In vivo, in vitro and ex vivo efficacy studies.
2. Analysis of skin surface topography-Analysis of lines, pores, texture. (Optical and Laser Profilometry). Applications and comparison of imaging methods with each other. Evaluation of cell-promoting substances and anti-aging cosmetics.
3. Determination of stratum corneum hydration-Efficiency of moisturizing products. Electrical methods, Absorption of infrared radiation.
4. Determination of transdermal water loss- Evaluation of moisturizing products but also of products that damage the lipid-epidermal barrier. Open and closed chamber method.
5. Physicochemical principles of the sebum determination method of the skin and scalp – Evaluation of sebum regulating products.
6. In vivo methods for the determination of skin melanin. Spectrophotometry in the determination of melanin. Evaluation of whitening cosmetics and dermatological products for vitiligo. In vitro methods for the evaluation of skin whiteners. Biophysical methods for evaluating erythema and effectiveness of anti-inflammatory cosmetics.
7. Skin pH quantification. Effect of cosmetic cleansers on skin pH. Evaluation of cleaning products. Model SPM (Sebum-pollution model, SPM).
8. Physicochemical principles of the method for determining skin elasticity. Evaluation of topical healing products and anti-aging treatments.
9. Use of ultrasound in the evaluation of products to increase skin collagen (anti-aging and healing) and skin hydration. Use of ultrasound to evaluate nail strengthening products.
10. Evaluation of exfoliating products. Dansyl chloride method- keratinocyte collection strips – UV lamp.
11. Electron permeability (TEM) and scanning (SEM) electron microscopy, spectroscopic and mechanical methods for evaluating the effectiveness of hair cosmetics. Differential scan calorimetry for hair repair products. Angular photometry for the evaluation of brightness and color.
12. In vivo evaluation of the effectiveness of a sunscreen product for ultraviolet B radiation: Method of measurement using a solar simulator of the Sun Protection Factor, SPF. In vitro methods
13. Evaluation of the effectiveness of a sunscreen product for ultraviolet A radiation (UVA protection factor). In vivo and in vitro methods. Critical wavelength method.
14. Evaluation of effectiveness of antiperspirants and deodorants. High performance liquid chromatography and gas chromatography applications in combination with mass spectroscopy.
15. In vitro and in vivo methods for the evaluation of transdermal absorption of the ingredients contained in cosmetic and topical products. Structure-action relations. Effect of lipophilicity. In silico models of the effect of lipophilicity on percutaneous absorption. Methods for the determination of lipophilicity of bioactive ingredients and excipients.
16. Skin equivalents and application in the evaluation of the effectiveness of cosmetics and dermal products.
Laboratory exercises
1. Measurement of transdermal water loss by the closed chamber method after the use of degreasing agent. Diagram construction-interpretation.
2. Measurement of transdermal water loss by the closed chamber method after the use
of a factor that strengthens the lipid-epidermal barrier. Diagram construction-interpretation.
3. Determination of skin color (Pigment darkening-Evaluation of whitening products after two months of application).
4. Determination of skin hydration after a certain time of application of O / W and W / O cosmetic cream. (Evaluation of moisturizing products). Diagram construction-interpretation-comparison.
5. Measurement of skin sebum with a sebumeter (Evaluation of sebum regulating products). Skin sebum measurement using sebum collection strips. Recording and evaluation of results.
6. Scalp sebum measurement with a sebumeter (Evaluation of sebum regulating shampoos).
7. Identification and imaging of skin exfoliation (Evaluation of moisturizing products). Measurement and imaging of scalp exfoliation (Evaluation of anti-dandruff products). Use of keratinocyte collection films – UVA photography.
8. Skin pH measurement. Effect of cleansing soap and liquid cleanser on skin pH. Measurement of pH at regular intervals after application. Diagram construction. Comparison.
9. Determination of skin elasticity. Evaluation of anti-aging products. Evaluation of healing products.
10. Measurement and imaging of skin microtopography with the method of optical permeability profilometry. 3D copy making. (Evaluation of anti-wrinkle products).
11. Measurement and imaging of skin microtopography with the method of UVA scanning (Evaluation of anti-wrinkle products).
12. Measurement of the Sun Protection Factor (SPF) and critical wavelength in vitro with ultraviolet spectrophotometer (Evaluation of sunscreen products).
13. Determination of lipophilicity of a mixture of preservatives (parabens) with high performance liquid chromatography. In silico prediction of percutaneous absorption.
14. Determination of lipophilicity of a mixture of preservatives (parabens) by the shake flask method in an octanol-water system. In silico prediction of percutaneous absorption.
15. Determination of percutaneous absorption by Franz cells and high performance liquid chromatography. Use of skin equivalents.