In HPTLC, how is each band typically quantified?

In HPTLC, how is each band typically quantified?

• A. Mass spectrometer
• B. Densitometer
• C. Ruler
• D. Buiret protein assay

Answer: (B)

In HPTLC, bands are quantified by measuring the optical signal from each band with a densitometer or scanner. After development, the plate is scanned or illuminated and the amount of light absorbed or reflected by each band is recorded, producing a densitometric profile where each band appears as a peak. The height or, more commonly, the area under each peak is proportional to the amount of analyte in that band. By comparing these signal values to standards with known amounts, you convert the densitometric data into concentration or quantity for each band. This on-plate quantification works with the different detection modes used in HPTLC, such as color, UV absorbance, or fluorescence after derivatization. A ruler would only indicate band position or length, not how much substance is present, while mass spectrometry is not the typical on-plate quantification method for routine HPTLC, and a Biuret assay measures total protein in a solution rather than the amount in individual bands.

In HPTLC, bands are quantified by measuring the optical signal from each band with a densitometer or scanner. After development, the plate is scanned or illuminated and the amount of light absorbed or reflected by each band is recorded, producing a densitometric profile where each band appears as a peak. The height or, more commonly, the area under each peak is proportional to the amount of analyte in that band. By comparing these signal values to standards with known amounts, you convert the densitometric data into concentration or quantity for each band. This on-plate quantification works with the different detection modes used in HPTLC, such as color, UV absorbance, or fluorescence after derivatization. A ruler would only indicate band position or length, not how much substance is present, while mass spectrometry is not the typical on-plate quantification method for routine HPTLC, and a Biuret assay measures total protein in a solution rather than the amount in individual bands.