sebumeter, corneometer,tewl, m.pharm analysis, pharmaceutical analysis, food analysis, cosmetic analysis and evaluation, modern bio analytical techniques, advanced pharmaceutical analysis, phamaceutical validation

1. SEBUMETER,CORNEOMETER,TRANS-
EPIDERMAL WATER LOSS
SUBMITTED TO:
Mrs. MANJU S.V, M PHARM
PROFESSOR
DEPT. OF PHARMACEUTICAL ANALYSIS
KARNATAKA COLLEGE OF PHARMACY
BANGALORE
SUBMITTED BY:
S.GOKULRAJ
M PHARM 2nd SEMESTER
DEPT.OF PHARMACEUTICAL ANALYSIS
KARNATAKA COLLEGE OF PHARMACY
BANGALORE
SUBJECT: COSMETIC SCIENCE AND EVALUATION
1
KARNATAKA COLLEGE OF PHARMACY

2. CONTENT
 SEBUMETER
 CORNEOMETER
 TEWL (TRANS EPIDERMAL WATER LOSS)
2
KARNATAKA COLLEGE OF PHARMACY

3. SEBUM
 Excess oiliness or excess dryness affects cosmetic
appearance of the skin.
 Hence, estimation of oiliness is important to decide on
the correct regimen to achieve cosmesis.
 Sebum is an oily secretion from the sebaceous gland.
Sebum waterproofs and lubricates the skin and hair of
mammals. Sebum affects the permeability of skin and
absorptivity of water.
 It protects skin against bacteria, fungi. It limits
evaporation, permeation of pharmaceutical
preparation and other active and non-active substances
3
KARNATAKA COLLEGE OF PHARMACY
SEBUM

4. SEBUMETER
 Sebumeter is a device by which sebum can be
quantified from any area of skin in an objective
manner.
 It was invented by Antoine Kawam, who patented it
in the year 1992.
4
KARNATAKA COLLEGE OF PHARMACY

5. PRINCIPLES OF SEBUMETER
 The measurement is based on the principle of grease
spot photometry.
 The measuring head of the cassette with its special
tape is placed on the skin.
 It is then inserted into a slot of the device, where the
transparency is measured by a light source passing
through the tape.
 A photocell measures the transparency.
 A microprocessor calculates the result, which is
shown on the display in mg sebum/cm2 of the skin.
5
KARNATAKA COLLEGE OF PHARMACY

6. Sebumeter Probe (Cartridge)
 The measuring head of the Cartridge exposes a 64 mm²
measuring section of the tape.
 For a measurement the tape is transported forward by a
trigger at the side of the Cartridge to expose a new section of
the tape. The used tape is rewound inside the cassette.
 One Cartridge can be used for approx. 450 measurements.
 The scale from 1-0 on the trigger shows how much of the tape
is still unused.
 For hygienic reasons when exhausted, the Cartridge is simply
replaced.
 The instrument has an accuracy of ±5%.
 The reading of sebum may be displayed as a number or as
type of skin i.e. dry; dry/normal; normal; normal/oily; oily.
6
KARNATAKA COLLEGE OF PHARMACY

7. Mechanism of Sebumeter
 It is based on the principle that when
sebum is deposited on a translucent
element, such as a frosted glass or plastic
plate or strip, the element becomes
increasingly transparent.
 Greater the amount of sebum applied, the
greater is the transparency produced.
 The measuring head of the cassette with its
special tape is placed on the skin.
 It is then inserted into a slot of the device.
 Light passing through this sebum covered
translucent element is then measured
using a photoelectric receiver.
 A microprocessor calculates the result,
which is shown on the display in mg
sebum/cm2 of the skin.
7
KARNATAKA COLLEGE OF PHARMACY

8. Measurement of sebum
 Sebum is an oily secretion from the sebaceous gland.
 Sebum waterproofs and lubricates the skin and hair of
mammals.
 Sebum affects the permeability of skin and absorptivity
of water.
 Protects skin against bacteria, fungi.
 Sebaceous glands often go into overdrive during
puberty, and the excess sebum can cause oily skin,
odors, and acne.
 There are a number of disorders associated with sebum
and the sebaceous glands.
 Hence measurement of natural presence of sebum is of
particular interest to dermatologists and cosmeticians.
8
KARNATAKA COLLEGE OF PHARMACY

9.  Lipids are synthesized at a constant rate in sebaceous
glands and secreted onto skin surface an average of 8
days after synthesis.
 As a result measurement of the sebum content of a skin
specimen of known surface area should allow
calculation of the sebum production rate which has
been occurring in vivo.
 Average sebum production rate of scalp is
1.45mg/10sq.cm/3hr
9
KARNATAKA COLLEGE OF PHARMACY

10. 10
KARNATAKA COLLEGE OF PHARMACY

11. Advantages of the Sebumeter
 Quick and very easy measurements
 Zero calibration
 Probe is small and lightweight
 The accuracy of the device can be easily checked
 Constant pressure on the skin
11
KARNATAKA COLLEGE OF PHARMACY

12. Applications
 Used in dermatological
 It is important for claim support and efficacy testing
of all kinds of cosmetic and pharmaceutical products.
 Determining the sebum level of the skin surface as
well as on scalp and hair
12
KARNATAKA COLLEGE OF PHARMACY

13. CORNEOMETER
 The World's Most Popular Skin Hydration Measurement
Instrument.
 For more than 30 years the Corneometer has provided the
worldwide most used method to reproducibly and
accurately determine the hydration level of the skin
surface (stratum corneum).
 This is documented by the numerous scientific literature
in which the terms "corneometry" and skin hydration
measurements are inseparable
13
KARNATAKA COLLEGE OF PHARMACY

14. MEASUREMENT PRINCIPLE
 The measurement is based on capacitance measurement of a
dielectric medium.
 The corneometer measures the change in dielectric constant due
to skin surface hydration changing the capacitance of precision
capacitor.
 The measurement can detect even slight changes in the hydration
level.
 The corneometer measures in arbitrary units from 0 to 120.
14
KARNATAKA COLLEGE OF PHARMACY

15. Advantages of the Corneometer
 very quick measurement (1 s)
 Continuous measurements
 Substances on the skin (e.g. salts or residues of topical
applied products) have only minimal influence due to
capacitance measurement.
 The measurement depth is very small (10-20 μm of the
stratum corneum) (e.g. from the blood vessels).
 The probe is small and lightweight for easy handling
and measurement on all body sites (e.g. lips etc.).
 The spring in the probe head ensures constant pressure
on the skin enabling exact, reproducible measurements
15
KARNATAKA COLLEGE OF PHARMACY

16.  The accuracy of the Corneometer probe and the
penetration depth of the scatter field can be checked
easily anytime.
 The probe head can quickly be cleaned
 Worldwide established as "corneometry" with a broad
range of studies.
 The Corneometer had been used to determine the state
of the skin of the astronauts on board of the
International Space Station (ISS).*
 The Corneometer is explicitly recommended is the
latest guideline for skin water measurements by the
experts of EEMCO (European group on efficacy
measurement and evaluation of cosmetics and other
products)
16
KARNATAKA COLLEGE OF PHARMACY

17. 17
KARNATAKA COLLEGE OF PHARMACY

18. Application
 The basic measurement for all bio-medical and cosmetic
applications.
 Ideal instrument for formulation, claim support and efficacy
& safety testing of all cosmetics & skin care products raw
materials, pharmaceuticals, household products,
detergents, food and food supplements and many more
 Typical claims (examples) substantiated with the
Corneometer: hydrating/moisturizing, against dry skin, for
sensitive skin, protecting, restoring/repairing, supports
healing, soothing, normalizing, vitalising, and many more.
 Used as standard in dermatological basis research in
humans and animals.
 Occupational health assesses this parameter to underline
the importance of skin protection measures
18
KARNATAKA COLLEGE OF PHARMACY

19. TEWL (Trans Epidermal Water Loss)
Definition:
 The measurement of quantity of water that passes from
inside a body through the epidermal layer to
surrounding atmosphere via diffusion and evaporation
processes.
 Measurement of TEWL
 Identifying skin damage
 Environmental factors
 Moisture content
19
KARNATAKA COLLEGE OF PHARMACY

20. The instrument used to measure TEWL
(Tewameter)
Measurement Principle
 A certain evaporation of water from the skin takes always place as
part of the normal skin metabolism.
 However, as soon as the barrier function of the skin is slightly
damaged, the water loss will increase.
 Therefore this measurement is a basis for all cosmetic and
dermatological research.
 The Tewameter probe measures the density gradient of the water
evaporation from the skin indirectly by the two pairs of sensors
(temperature and relative humidity) inside the hollow cylinder.
 This is an "open chamber" measurement.
 This method is the only to assess the TEWL continuously without
influencing its micro environment. The measured values express the
evaporation rate in g/h/m².
20
KARNATAKA COLLEGE OF PHARMACY

21. 21
KARNATAKA COLLEGE OF PHARMACY

22. dm/dt = - D . A . dp/dx
 A= surface [m2]
 m = water transported [g]
 t = time [h]
 D= diffusion constant [= 0.0877g / m * (h(mmHg)) ]
 p = vapour pressure of the atmosphere [mm Hg]
 x = distance from skin surface to point of
measurement [m]
22
KARNATAKA COLLEGE OF PHARMACY

23. Advantages
 Extremely accurate and quick
 Small size of the probe head minimizes the influence
of air
 Easy to handling
 No waiting time between the measurements
 Display of RH and °C separately
 Special calculation i.e SSWL (skin surface water loss)
 Accuracy of the probe can be checked anytime
23
KARNATAKA COLLEGE OF PHARMACY

24. Application
 Scalp, lip, hair measurements
 Sweat studies
 Used in vitro testing
 Used for dermatological research
 Veterinary dermatology and zoology
 Used for textile/food/paper/tissue industry
24
KARNATAKA COLLEGE OF PHARMACY

25. THANK YOU
25
KARNATAKA COLLEGE OF PHARMACY