INSTRUMENTAL ANALYSIS

Instrumental Tests: Verification of Product Efficacy Through Objective and Scientific Methods

Instrumental tests play a critical role in objectively and scientifically proving the claims of products in the cosmetic, personal care, pharmaceutical, and similar industries. These tests are carried out using non-destructive testing equipment on human subjects under controlled conditions and generally under the supervision of a dermatologist (or a physician specialized in the relevant field). Instrumental tests complement the subjective data obtained from application tests and provide objective, measurable, and reproducible data on product performance.

Application Areas and Importance of Instrumental Tests:

Instrumental tests are widely used, especially in the following areas:

• Cosmetic and Personal Care Products: Moisturizers, anti-aging creams, sunscreens, skin lighteners, anti-acne products, hair care products, etc.

• Dermatological Products: Topical products used in the treatment of skin conditions such as eczema and psoriasis.

• Medical Devices: Wound dressings, topical antiseptics, medical devices that come into contact with the skin.
  
  

Through these tests:

• The efficacy of products is objectively proven.

• The safety is evaluated.

• The claims are supported by scientific data.

• Quality control processes are improved.

• Product development efforts are guided.

Non-Destructive Testing Equipment and Measurable Parameters in Instrumental Tests:

In instrumental tests, non-invasive methods and devices are used to measure various characteristics of the skin, hair, and other tissues. Here are the most commonly used parameters and related devices:

1. Skin Hydration Measurement (Stratum Corneum Hydration):

• Device: Corneometer (e.g., Corneometer® CM 825, Courage + Khazaka electronic GmbH)

• Principle: Capacitance measurement. The device measures the dielectric constant of the stratum corneum (the outermost layer of the skin), which is correlated with its water content.

• Measurement Unit: Corneometer Unit (C.U.)

• Evaluation: Higher values indicate higher skin hydration.
  
  

2. Skin Water Loss Measurement (Transepidermal Water Loss - TEWL):

• Device: Tewameter (e.g., Tewameter® TM 300, Courage + Khazaka electronic GmbH)

• Principle: Open chamber principle or closed chamber principle. The device measures the amount of water evaporating from the skin surface.

• Measurement Unit: g/m²/h

• Evaluation: Low TEWL values indicate a healthy skin barrier function. High values indicate a damaged barrier function and increased water loss.
  
  

3. Sebum Measurement (Skin Oiliness):

• Device: Sebumeter (e.g., Sebumeter® SM 815, Courage + Khazaka electronic GmbH)

• Principle: Photometry. A special tape absorbs sebum from the skin surface, and its light transmittance is measured.

• Measurement Unit: µg/cm²

• Evaluation: Used to determine oily, normal, and dry skin types and to evaluate the efficacy of products that affect sebum production.
  
  

4. Skin pH Measurement:

• Device: Skin-pH-Meter (e.g., Skin-pH-Meter® PH 905, Courage + Khazaka electronic GmbH)

• Principle: Potentiometric measurement with a glass electrode.

• Measurement Unit: pH

• Evaluation: Used to evaluate whether the acid mantle of the skin is healthy. Normal skin pH is slightly acidic (between 4.5 and 5.5).
  
  

5. Skin Color Measurement (Skin Tone and Pigmentation):

• Device: Mexameter (e.g., Mexameter® MX 18, Courage + Khazaka electronic GmbH) or Chromameter (e.g., CR-400, Konica Minolta)

• Principle: Spectrophotometry or Chromametry. The device analyzes the light reflected from the skin to determine melanin and hemoglobin concentrations.

• Measurement Unit: Melanin index (M.I.), Erythema index (E.I.), or Lab* color system values.

• Evaluation: Used to evaluate skin tone, pigmentation disorders, the efficacy of skin-lightening products, and sun damage.

6. Skin Redness Measurement (Erythema):

• Device: Mexameter (e.g., Mexameter® MX 18, Courage + Khazaka electronic GmbH)

• Principle: Spectrophotometry. The device analyzes the light reflected from the skin to determine hemoglobin concentration.

• Measurement Unit: Erythema index (E.I.)

• Evaluation: Used to evaluate skin redness, inflammation, and irritation.
  
  

7. Skin Elasticity Measurement (Elasticity):

• Device: Cutometer (e.g., Cutometer® dual MPA 580, Courage + Khazaka electronic GmbH) or ElastiMeter

• Principle: Suction or torsion method. The device applies a controlled vacuum or torsion to the skin and measures its deformation and ability to return to its original state.

• Measurement Unit: Various parameters such as R parameters (R0-R9) and U parameters (Uv, Ue, Uf, Ur, Ua) are used.

• Evaluation: Used to evaluate the elasticity, firmness, and biomechanical properties of the skin. Important in evaluating the efficacy of anti-aging products.
  
  

8. Skin Wrinkle Measurement (Topography):

• Device: Visioline (e.g., Visioline® VL 650, Courage + Khazaka electronic GmbH) or Primos

• Principle: Optical profilometry or fringe projection. The device creates a three-dimensional image of the skin surface and measures the depth, length, and volume of wrinkles.

• Measurement Unit: µm, mm, mm³

• Evaluation: Used to evaluate the appearance of wrinkles and fine lines and to prove the efficacy of anti-aging products.
  
  

9. Skin Surface Structure (Roughness):

• Device: Visioscan (e.g., Visioscan® VC 20plus, Courage + Khazaka electronic GmbH) or Skin-Visiometer

• Principle: Imaging and analysis method. The device takes high-resolution images of the skin surface and analyzes roughness parameters.

• Measurement Unit: Parameters such as SEr (Surface evaluation roughness) and SEsm (Surface evaluation smoothness) are used.

• Evaluation: Used to evaluate skin roughness, texture, and micro-relief.
  
  

10. Skin Pore Assessment:

• Device: Visiopor (e.g., Visiopor® PP 34, Courage + Khazaka electronic GmbH) or Visioscan

• Principle: Imaging and analysis method. The device takes high-resolution images of the skin surface and analyzes the number, size, and area of pores.

• Measurement Unit: Number of pores, pore area (mm²)

• Evaluation: Used to evaluate the appearance of pores and to prove the efficacy of pore-minimizing products.
  
  

Presentation of Test Results:

Instrumental test results are presented in a comprehensive report that includes graphs, charts, statistical data, before/after photographs, and expert interpretations, depending on the device used and the parameter measured.