Validation of quantitative TLC analysis of test dye samples using a Datacolor 3890 colour analyzer was performed. Chromatograms were recorded in the visible region and the results given were on-plate diffuse reflectance spectra of the chromatographic spot, its lightness, chromaticity and hue. The results showed low total R.D.S. for the detremination of reflectance and lightness of the chromatographic spots (0.1-2.8% for low concentration level) with negligible instrumental error (0.01-0.04%). The applicability of the proposed method was tested with quantitative TLC analysis of diffuse and distorted spots of amino acids obtained on non-homogenous laboratory-prepared plates. Validation of the results has been made by comparison with image analysis and salt-scanning densitometry. The best results (the lowest R.D.S., detection limit and limit of quantification) were obtained by measuring reflectance with the Datacolor system. Densitometry and image analysis resulted in a lower precision (R.D.S.>10%) and significant instrumental error.

Tekstilna tehnologija