1. INTRODUCTION ON HPTLC PRINCIPLE
HPTLC is a well known and versatile separation method which shows a lot of advantages and options in comparison to other separation techniques.
The method is fast and inexpensive. It does not require time consuming pretreatments.
The basic difference between conventional TLC and HPTLC is only in particle and pore size of the sorbents.
HPTLC is an entire concept that includes a widely standardized methodology based on scientific facts as well as the use of validated methods for qualitative and quantitative analysis.
PRINCIPLE
Principle Same theoretical principle of TLC.
The principle of separation is adsorption.

2. ADVANTAGES
High resolution of zones due to higher number of theoretical plates.
Shorter developing times
Less solvent consumption
Enormous flexibility
Parallel separation of many samples with minimal time requirement
Simplified sample preparation due to single use of the stationary phase.

3. Major difference between TLC and HPTLC
Parameter TLC HPTLC
Mean particle size µm µm
Distribution µm µm
Layer thickness µm µm
Plate height µm µm
Separation time min min
Sample volume µL µL

4. Slurry preparation Coating the plate Drying the plate
Preparation of plate for HPTLC
Slurry preparation
Coating the plate
Drying the plate

5. BINDERS TO BIND THE SILICA GEL TO THE TLC PLATE GYPSUM
USE
TO BIND THE SILICA GEL TO THE TLC PLATE
STRONGEST BINDERS
GYPSUM
PLASTER OF PARIS
SUPPORT
FOR EXTRA STRENGTH, POLYVINYL ALCOHOL OR PYRROLIDONE IS USED

6. INSTRUMENTATION OF HPTLC
1. Plate coaters
2. Drying racks
3. Plate cutters
4. Immersion device
5. Plate heater
6. Sample application
7. Development chamber
8. Derivatization devices
9. Scanning densitometer

7. Flow diagram of HPTLC Instrumentation:

8. Semi Automatic Sample Applicator
Usual concentration of applied samples 0.1 to 1 µg / µl for
qualitative Analysis. Applicators use spray on or touch and deliver technique for application.
The instrument is suitable for routine use for
medium sample throughout . In contrast to the
Automatic TLC sampler , changing the sample
the Linomat requires presence of an operator.
With the linomat , samples are sprayed onto
the chromatographic layer in the form of
narrow bands.
During the spraying the solvent of the sample
evaporates almost entirely concentrating the sample
Into a narrow band of selectable length.

9. TWIN TROUGH OR DEVELOPMENT CHAMBER
Low solvent consumption: 20 mL of solvent is sufficient for the
development of a 20x20cm plate.
This not only saves solvent , but also reduces
the waste disposal problem
Reproducible pre –equilibrium with
Solvent vapor: For pre-equilibration, the
TLC plate is placed in the empty trough
opposite the trough which contains
the pre-conditioning solvent. Equilibration
can be performed with any liquid and
for any period of time.
Start of development : It is started
only when developing solvent is introduced
into the trough with the plate.

10. Reasons for Derivatization:
Changing non-absorbing substance into detectable
derivatives.
Improving the detectability and induce fluoroscence
Detecting all sample components.
Selectivity detecting certain substance.
DERIVATIZATION DEVICE
Spraying
Drying
Derivatization through gas phase

11. Photo documentation
Detection under UV light is first choice - non destructive . WINCATS Is used for it.
Spots of fluorescent compounds can be seen at 254 nm (short wave length) or at 366 nm (long wave length) 
Spots of non fluorescent compounds can be seen - fluorescent stationary phase is used - silica gel GF

12. Scanning densitometer
The scanner is connected to a computer.
The scanner features three light sources ,a deuterium lamp , a tungsten lamp and a high pressure mercury lamp.
The scanning speed is selectable between 1 and 100 mm/s

13. EXPERIMENT STEP 1:The tracks made by the sample applicator
STEP 2: Drying in the hot air oven at 100 degree C.
STEP 3:The plate in the development chamber.

14. STEP 4: The sample is kept in the chamber for photo documentation
STEP 4: The sample is kept in the chamber for photo documentation . The result is obtained under 254 nm of light
STEP 5: Then it is kept in the scanner and according to the spots we get the peaks in the WINCAT SOFTWARE.

15. APPLICATIONS. Food analysis. Pharmaceutical industry
APPLICATIONS * Food analysis * Pharmaceutical industry * Clinical applications * Industrial applications * Forensic *cosmetics

16. AAS DETECTORS FUTURE PLANS
Principle of atomic absorption spectrophotometer
Working
AAS
Principle of various detectors used in GC
Their flow diagrams
DETECTORS