What is HPTLC?
HPTLC is the High-Performance version of Thin Layer Chromatography and a state-of-the art technique for plant analysis. It features significantly shorter developing times, lower solvent consumptions and improved resolution. Highly reproducible results and traceable records are achieved through a standardized methodology and the use of suitable instruments (typically controlled by software) for all steps of the analysis. A system suitability test is used to qualify results.
The stationary phase is a HPTLC glass plate or aluminum sheet coated with a uniform thin layer (typically 200 micron) of porous particles (2 – 10 μm) with an average particle size of 5 μm. The layer typically consists of silica gel with a pore size of 60 Angstroms, a polymeric binder and a so called fluorescence indicator (F254). The standard format of the plate is 20×10 cm.
The apparatus for HPTLC consist of
- A device suitable for application of samples as bands providing control of dimension and position of the application as well as applied sample volume
- A suitable chromatographic chamber (typically a twin trough chamber) providing control of saturation and developing distance
- A device suitable for controlling the activity of the stationary phase via relative humidity
- A device suitable for reproducible drying of the developed plate
- Suitable devices for reagent transfer and heating as part of the derivatization procedure
- A device suitable for electronic documentation of chromatograms under UV 254 nm, UV 366 nm, and white light
- For quantitative determinations a densitometer or image evaluation software