J. Chromatogr. Sci. 33, 316-320 (1995). Use of the addition of a-, b-, g-, and hydroxypropyl-b-cyclodextrins to aqueous mobile phases to enhance the migration of p-nitroanilines and their analogues on TLC. Determination of the equilibrium binding constants for the solute-cyclodextrin complexes formed in the mobile phase. Comparison of the results obtained using silica gel and polyamide plates. Urea, which is used to solubilize the cyclodextrins in aqueous solutions, is also found to increase the migration of the compounds.

J. Chromatogr. A 803, 235-239 (1998). Modeling of ion-pair HPLC separations by using continuous OPLC. Study of the distribution of several cationic ion-pairing reagents on the layer with mobile phases containing different quaternary ammonium salts, which volumes varied between 4.5 to 67.5 cm3 equivalent to a 1 to 15 bed volume of the given layer. Measurement of the concentration of the reagents after chromatography in 10 samples of the stationary phase used.

Chromatographia 54 (9/10), 669-672 (2001). 2D-TLC of a mixture of saponins obtained from the roots of Medicago sativa with a sorbent gradient, first development on RP-18 and in the perpendicular direction on silica gel. Comparison of the results obtained with those acquired by 2D-TLC on the same monolayer stationary phase. The saponin mixture consisting of 18 components could be separated into 17 individual saponins by conventional 2D-TLC. When using sorbent gradient the spots were spread over a larger surface area of the silica gel plate.

J. Liq. Chrom. & Rel. Technol. 26, 2611-2627 (2003). A new OPLC separation procedure has been developed for single- and multi-channel separation using a non-segmented sorbent bed and flowing eluent wall (FEW) for operating segmentation. The FEW detaches the sorbent bed into active and non-active parts regarding separation during the process. Only mobile phase is introduced into the non-active part, while, for the active part, eluent and also the sample can be admitted, thus the non-homogeneous part of the sorbent is excluded from the separation process. OPLC of ascorbigen, cabbage extract and a dye mixture on silica gel with e.g. chloroform - methanol - acetic acid 90:10:1 resp. toluene. Detection under UV 285 nm.

Phytochem. Anal. 20, 154-158 (2009). TLC of the purgative constituents of rhubarb (sennoside A and sennoside B) on silica gel with 1-propanol - ethyl acetate - water - acetic acid 40:40:30:1. After drying detection by spraying with 10 % sulfuric acid and heating. For the eastern blotting assay the developed TLC plate was dried and sprayed with isopropanol - methanol - water 1:4:16. Transfer by using a PVDF membrane sheet for further treatment.

J. Chromatogr. A 1577, 101-108 (2018). In order to overcome the difficulty of the interpretation of the MS signals present at a low intensity for unknown degradation products or impurities, a new strategy and open-source software called eicCluster was developed. It offered unsupervised machine learning algorithms and powerful interactive visualization tools that made data processing fast and intuitive. The low-intensity HPTLC-HRMS signals were highlighted in a stressed formulation by using eicCluster. Thus, even compound ions present at low intensities were separated in subclusters from background signals (in silico highlighting). The respective preprocessing led to intensity-agnostic signals and the t-SNE algorithm clustered mass signals based on their similarity. The resulting 2D maps allowed a new view on the data set to such low-intensity target molecules in complex mixtures. Moreover, the targeted on-surface synthesis of degradation products (in situ highlighting) was shown to support a fast structure elucidation, when standards are not commercially available. It allowed a better understanding of the proposed degradation reactions in the formulation. Comparison with the results of stressed samples as well as the proposed degradation products of on-surface synthesis proved that in silico and in situ signal highlighting substantially eased structure elucidation and data processing.

for thin-layer chromatography). TLC of herbal constituents, isopimaric acid, sesamin, paulownin, curolione, curcumo, artemether, emodin, artemisinin, gossypol and gallic acid. Detection by spraying with 1 % vanillin in 60% sulphuric acid. Pharmaceutical research, Chinese herbal medicines.

Part 2. Chromatographic applications. Anal. Chim. Acta 227, 155-163 (1989). TLC of coumarin-6-sulphonyl chloride derivatized amino acids on silica with chloroform – ethyl acetate – methanol – acetic acid 20:20:9:1. Detection by absorbance at 320 nm, or by spraying with ethanol, by fluorescence 366/>500 nm at 77°K. Detection limits in the ng level of analyte for both procedures.