Densitometric Scanning
Definition
The HPTLC quantitation step. After the developed plate dries, a Camag TLC Scanner 4 sweeps a narrow slit of UV or visible light across each track and records the absorbance or fluorescence at every position. The scan converts a visual band pattern into a chromatogram with peak areas that calibrate against standards.
- Technique
- HPTLC quantitation step
- Instrument example
- Camag TLC Scanner 4
- Measures
- UV or visible absorbance/fluorescence
- Output
- Chromatogram with calibrated peak areas
Common questions
Why is densitometric scanning needed after an HPTLC plate is developed?+
Without it, the plate only shows a visual pattern of separated bands; the scanner converts that pattern into a numeric chromatogram whose peak areas can be measured and compared against calibration standards for quantitation.
Can densitometric scanning detect compounds that are not visible to the eye?+
Yes, scanning in UV or with fluorescence mode can register bands too faint or colourless for visual inspection, extending detection beyond what a simple visual read of the plate would catch.
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