JAOAC Int. 84, 1265-1276 (2001). Within the process of the International Conference on Harmonization (ICH), 2 guidelines were released containing a standardized terminology, a verified model of requirements for the validation of analytical procedures, and some guidance in the practical aspects of conducting validation studies in pharmaceutical analysis. For planar chromatographic procedures, which may be used at different levels either in qualitative identity testing, assays, semiquantitative limit tests, or quantitative determination of impurities, it was tried to transfer these formal requirements into practical approaches for validation. Topics like prevalidation considerations and validation (identification, testing for impurities with the limit test, testing for impurities by using quantitative procedures, robustness, quality assurance in routine work) were discussed.

J. Planar Chromatogr. 28, 106-114 (2015). An overview of adsorption characteristics of 3-cyanopropylsiloxane-bonded silica gel, and its application as sorbent are presented. Due to the unique characteristics caused by the presence of both hydrophilic and hydrophobic parts on its surface, 3-cyanopropylsiloxane-bonded silica gel can be used for the separation of various classes of substances in both normal- and reversed-phase chromatography.

Symp. on Advances in Liq. Chromatogr. Szeged, Hungary 1982. Considerable interest in the role of the specific surface area of the adsorbent in thin-layer chromatography is due to the growing importance of this method as a pilot technique for determing the optimum conditions of mixture separation on both analytical and preparative scales.

J. Chromatogr. 287, 385-390 (1984). Study to compare the reversed-phase thin-layer chromatography behaviour of some barbituric acid derivatives on various chemically bonded reversed-phases with different eluents.

J. Planar Chromatogr. 2, 180-189 (1989). Properties of the sample and matrix effects, that affect quantitative TLC using scanning densitometry are discussed. The sorbent matrix influences the shape of calibration curves, and impurity gradients, resulting from contamination of the layer or application of derivatizing reagents are common sources of baseline instability. Chemical reactions catalyzed by the sorbent layer, which may also involve oxygen or light, are a source of sample instability. Fluorescence quenching and fluorescence enhancement effects can influence the reliability of quantification in the fluorescence mode. Some practical examples of the effects are discussed. Comparison of HPLC and TLC.

CLB Chemie in Labor und Biotechnik 2, 55-60 (1999). A comparison between a TLC Scanner and a video-system as tools in quantitative evaluations of HPTLC chromatograms. Discussion of the advantages and disadvantages of both systems.

Abstract No. 9923, IHCB (2009). HPTLC of several herbal formulations (tablets extracted with methanol) on silica gel with toluene - ethyl acetate 19:1. The fingerprint method was suitable for correct identification and for routine quality control of the herbal extracts.

Detection by spraying with 0.01 % dithizone in trichloromethane.