J. Sep. Sci. 43, 2981-2988 (2020). HPTLC of citicoline (1) and piracetam (2) in presence of their degradation products on silica gel with methanol - chloroform - ammonium chloride buffer 9:1:2. Quantitative determination by absorbance measurement at 230 nm. The hRF values for (1) and (2) were 15 and 85, respectively. Linearity was between 0.2 and 4 µg/zone for both (1) and (2). Intermediate precision was below 2 % (n=3). The LOD and LOQ were 56 and 180 ng/zone for (1) and 53 and 170 ng/zone for (2), respectively. Average recovery was 100.9 % for (1) and 99.8 % for (2).

J. Planar Chromatogr. 33, 219-229 (2020). HPTLC of carbamazepine (1) and its degradation product iminostilbene (2) on silica gel with petroleum ether - acetone 7:3. Quantitative determination by absorbance measurement at 230 nm. The hRF values for (1) and (2) were 12 and 63, respectively. Linearity was between 0.1 and 1.4 µg/zone for (1) and 0.1 and 1.2 µg/zone for (2). Intermediate precision was below 2 % (n=3). The LOD and LOQ were 0.03 and 0.09 µg/zone for (1) and 0.03 and 0.09 µg/zone for (2), respectively. Average recovery was  99.7 % for (1) and 99.7 % for (2).

Food Control. 22, 1154-1157 (2011). TLC of histamine in fish and fishery products on cellulose with ammonia - ethanol 1:3. Detection by spraying with Pauly's reagent (equal mixture of 20 mM sulfanilic acid in a 1 M HCl solution and 200 mM sodium nitrite solution, followed by adding 10 % anhydrous sodium carbonate in a 5 % ethanol solution). Color intensity was recorded using a digital camera, followed by imaging processing. Linearity was between 30 and 1000 ng/zone for histamine. Intermediate precision was below 5 % (n=3). The LOD was 20 ppm (2 mg/100 g). Recovery rate was between 93 and 98 %.

Food Control. 103, 111-118 (2019). Thin layer chromatography in tandem with surface-enhanced Raman scattering (TLC-SERS) of histamine in tuna samples on diatomaceous earth plates with ethanol - ammonia 3:1. Detection by spraying with Pauly's reagent (equal mixture of 20 mM sulfanilic acid in a 1 M HCl solution and 200 mM sodium nitrite solution, followed by adding 10 % anhydrous sodium carbonate in a 5 % ethanol solution). Gold nanoparticles were deposited on the plate zone and measurements were performed using a Raman spectrometer with an excitation laser wavelength of 785 nm.

J. Ethnopharmacol. 235, 361-374 (2019). HPTLC of colchicine (1) and withaferin A (2) in the polyherbal ayurvedic formulation Peedantak Vati (PV) on silica gel with chloroform - 
methanol - water - formic acid 140:13:2:4. Quantitative determination by absorbance measurement at 218 nm. The hRF values for (1) and (2) were 22 and 28, respectively. LOD and LOQ were 40 and 120 ng/zone for (1) and 120 and 240 ng/zone for (2), respectively.  

J. Chromatogr. A 1432, 140-144 (2016). 2-Aminoacetophenone (AAP) is closely correlated with the appearance of the sensory phenomenon of untypical aging off-flavor (UTA) in wine and is generally analyzed by GC/MS after being extracted from wines by liquid-liquid, solid-liquid or solid phase microextraction. Presentation of a rapid, selective and sensitive method for the determination of AAP in wine by HPTLC of the extracts, obtained by liquid-liquid extraction with t-butyl methyl ether followed by a basic cleanup, on amino layer with methylene chloride – toluene 7:3. Detection by dipping into n-hexane-paraffin solution and quantification by densitometry at 366/>400 nm using 2-amino-4-methoxyacetophenone as internal standard. The LOD and LOQ were 0.1 and 0.3 μg/L, respectively. The recovery was near 100 % for model, white and red wines, while AAP concentrations were >0.5 μg/L in UTA. The results indicated that the method enables the analysis of AAP in wines clearly below the odor thresholds and represents a rapid and convenient screening alternative to existing GC/MS methods.

(Hungarian). (Dehydrogenation accompanied decomposition of pyrido-pyrimidine carboxamide). TLC of 1,6-dimethyl-4-ox-1,6,7,8,9,9a-hexahydropyrido- (1,2a)-pyrimidine-3-carboxamide on silica with chloroform - methanol 92:8. Detection by UV. Photometry after elution.

J. Agric. Food Chem. 38, 1877-1880 (1990). One- and two-dimensional TLC on silica with dichloromethane - methanol 9:1, hexane - benzene - acetone 7:3:1; GC/MS after elution with methanol. Visualization under UV and by autoradiography.