Anal. Chem. 67, 3293-3299 (1995). Kinetic fluorescence detection (KFD) was employed to determine the concentration of two overlapped components after a TLC separation using two amino acids, glycine and glutamine as model analytes. Discussion of kinetic approach and the applicability and limitations of the direct trilinear decomposition (TLD) method using both synthetic and experimental data - TLC of glycine and glutamine on silica with 1-butanol - acetone - acetic acid - water 7:7:2:4 in a sandwich-chamber as mobile phase. After drying at 100 °C for 10 min the plate was dipped into a 0.05 % solution of o-phthalaldehyde in methanol, which contained 0.2 % 2-mercaptoethanol and 0.09 % Brij-35, immediately removed, visualization under UV 366 nm.

Anal. Sci. Vol. 13 Sup., 191-194 (1997). Study of the vertical concentration distribution of compounds on TLC plates by photoacoustic spectroscopy (PAS). Exhibition of irregular concentration profiles of the compounds in vertical direction under the given conditions, and tending to uppermost 61 mm thick layer. Discussion of the phenomenon in improving linearity of calibration curves compared to those obtained by reflectance densitometry.

J. Planar Chromatogr. 15, 204-209 (2002). Description of a new diode-array scanner in combination with a computer-controlled application system which meets all demands of modern HPTLC measurement, e.g. automatic application, simultaneous measurements at different wavelengths, and different linearization models enabling appropriate evaluation of all analytical questions. These aspects result in substantial improvement of in-situ quantitative densitometric analysis, and simultaneous recording at different wavelengths opens the way for chemometric evaluation, e. g. peak purity monitoring, which improves the accuracy and reliability of HPTLC analyses.

J. Chromatogr. Sci. 46 (6), 560-564 (2008). Quantitative TLC is performed with a digital imaging system with simple equipment and software. The method was used for the quantitative assay of cichoric acid in Echinacea purpurea. TLC on polyamide phase with chloroform - methanol - formic acid - water 3:6:1:1. Detection by spraying with 3 % aqueous aluminum chloride solution. Images of chromatograms were acquired with a standard digital camera under a UV lamp at 365 nm in a dark room. The three-dimensional grayscale digital image dataset (x, y, gray) was reduced to a two-dimensional dataset (distance, accumulative gray) and then plotted as a curve. For quantification the area under the curve (corresponding to cichoric acid) was integrated.

J. Chromatogr. Sci. 54 (4), 639-646 (2016). Presentation of a low-cost method for digital image analysis of the separation results of colorless analytes on TLC plates. Quantitative TLC-digital image analysis was performed using a universal staining reagent (iodine vapor), an office scanner and a commonly available software (Microsoft Paint) for analysis of red, green and blue colors (RGB values). Urinary creatinine is used as a model analyte to represent a sample in complicated biological matrices. TLC on silica gel with butanol – ammonia solution – water 4:1:5 up to 6 cm. Detection by exposure to iodine vapors for 30–60 min. The Green value offered the best results in the linear working range of 0.08 - 0.93 mg/mL. The precision (%RSD) was 2.0 % (n=10), and the LOD 0.24 µg per zone. Comparison of the urinary creatinine concentrations determined by TLC-digital image analysis using the green value calibration graph with results obtained by HPLC showed that both are well consistent.

Discussion of the selection of fitting functions, the determination of initial parameters, etc.

J. Chromatogr. 437, 97-107 (1988). Discussion of the advantages and disadvantages of using multi-element image sensors in densitometers versus conventional electromechanical TLC scanners. Consideration of both vacuum camera tubes of the video kind and semiconductor sensor. Semiconductor devices are deemed to be preferable to camera tubes.

J. Chromatogr. 466, 37-87 (1989). Review on application of liquid crystals in TLC with 7 references. Also, other applications.