J. Chromatogr. A 1182 (2), 219-225 (2008). UV imaging of spots on TLC plates while still wet with solvent. Imaging of spots of benzophenone during and after development by using a charge-coupled device camera. The limit of detection was 5 ng on a wetted plate and 3 ng on a dry plate. The relationship between peak area and sample loading was linear in the low nanogram range over an order of magnitude for both wet and dry modes. It was shown that UV measurements on wet glass plates suffer from low sensitivity; however, increased sensitivity was achieved by using aluminium plates. The separation process can be monitored by measurement of UV absorbance during TLC development on aluminium-backed plates.

J. Liq. Chromatogr. Relat. Technol. 39, 242-248 (2016). Review of the application of multivariate TLC retention data, the theory of hierarchical cluster analysis, principal component analysis and parallel factor analysis. Different applications such as exploring retention, lipophilicity analysis, quantitative structure–activity relationship modeling, solvent selection and comparison with other techniques were described.

J.Liquid Chromatogr. 8, 2875-2926 (1985). Discussion of optimization of instrumental parameters that influence resolution and signal-to-noise ratios in the recording of thin-layer chroMatograms by scanning densitometry. Proposition of a standardized method of determining sensitivity and detectability (used to evaluate the performance of a Shimadzu CS-910 scanning densitometer). Discussion of fluorescence enhancement reagents as a method of improving sample detectability in fluorescence mode as well as influence of the sorbent on position and intensity of the fluorescence emission signal.

Anal. Biochem. 171, 248-255 (1988). TLC of lipids on silica with methanol - ethanol - chloroform - NH3 1:49:6:6 or chloroform - methanol - acetic acid - water 60:45:5:3. Visualization by exposing to iodine vapor, by spraying with ninhydrin or molybdate. Chromatograms photocopied on transparent sheets, which are quantified by densitometry.

J. Planar Chromatogr. 2, 378-381 (1989). Reciprocal enrichment of two developing directions in instrumental TLC by optimization of separation applying Soczewinski’s principle. Identification with diffuse reflectance electronic spectra recorded directly from the spots of the separated substances, shown with diphenyl ether derivatives as examples.

J. Planar Chromatogr. 3, 104-110 (1990). Comparison of scanning by electro-mechanical means, which is standard in most of today’s densitometers, with electronic methods of scanning. The main advantage of the latter is much higher speed of data acquisition, which results in a higher throughput of the instrument. Electronic scanning also promises lower cost and simpler design because of the absence of moving elements.

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.