J. Planar Chromatogr. 34, 203-209 (2021). HPTLC of triclosan in toothpaste on silica gel with n-heptane - methyl tert-butyl ether - acetic acid 920:80:1. Detection by spraying with 2,6-dichloroquinone-4-chloroimide in 50 mL methanol, followed by spraying with an aqueous sodium carbonate solution (1 g/10 mL). Plates were scanned using a flatbed scanner. The hRF value for triclosan was 22. Linearity was between 100 and 1000 ng/zone. The LOD and LOQ were 46 and 91 ng/zone, respectively. Average recovery was 93.2 %.

J. AOAC Int. 103, 1167-1172 (2020). HPTLC of aminexil (1), niacinamide (2) and pyridoxine HCl (3) on silica gel with propanol - toluene - 33 % ammonia solution
20:30:1. Quantitative determination by absorbance measurement at 270 nm. Linearity was between 0.25 and 1.25 µg/zone for (1), 2 and 7 µg/zone for (2) and 3 and 7 µg/zone for (3). Intermediate precision was below 2 % (n=3). The LOD and LOQ were 20 and 60 ng/zone for (1), 180 and 540 ng/zone for (2) and 140 and 430 ng/zone for (3), respectively. Average recovery was 100.1 % for (1) and (2) and 101.1 % for (3). 

J. Chromatogr. A 1568, 188-196 (2018). Application of an advantageous combination, the desorption-based direct analysis in real time mass spectrometry (DART-MS) immediately after direct bioautography (DB), i.e., in the presence of microorganisms, bioassay medium and substrate reagent. The method offers a straightforward and efficient mass spectrometric detection of bioactive analytes within the bioautogram. It discriminated microorganism cells and highly polar bioassay medium ingredients which could otherwise stress the MS system. Investigation of DB-DART-MS for bioactive compounds in cosmetics using the Bacillus subtilis and Aliivibrio fischeri bioassays for detection of Gram-positive and Gram-negative antimicrobials, respectively, and the planar yeast estrogen screen for detection of estrogen-effective compounds. Study of the influences of three different bioassay matrices on the analyte response and DB-DART-MS performance on different layers (NP and RP) on the example of parabens in hand creams. Ion suppression was enhanced with increasing culture medium complexity. The mass spectrometric quantification by DB-DART-MS at the ng-level in situ each different bioautogram was verified by comparison to HPTLC-DART-MS. The total paraben content of hand creams 1 and 2 was 0.17–0.20% and 0.30–0.34%, respectively, depending on the method used. It proved that DB-DART-MS is a reliable qantitative bioanalytical hyphenation.

J. Planar Chromatogr. 20, 347-351 (2007). TLC of DTAB on soil, silica gel, alumina, and kieselguhr with fifteen mobile phases, such as aqueous solutions of ammonium sulfate and urea, with chamber saturation for 10 min. Detection by spraying with modified Dragendorff reagent. Among the systems studied the best system for selective separation of DTAB from multicomponent mixtures of other surfactants was kieselguhr - 0.1 M ammonium sulfate. Semi-quantitative determination by spot-area measurement.

J. Planar Chromatogr. 26, 119-124 (2013). HPTLC of methyl- (1), ethyl- (2), propyl- (3), and butylparaben (4) in cosmetics on cyanopropyl plates with water - acetonitrile - dioxane - ethanol 8:2:1:1+1 drop ammonia. Quantitative determination by absorbance measurement at 255 nm and by bioutographic analysis using Vibrio fischeri bacteria. LOD for (3) and (4) was 100 ng/zone, for (1) 80 ng/zone, and 69 ng/zone for (2). The LOQ for (3) and (4) was 120 ng/zone, for (1) 90 ng/zone, and 78 ng/zone for (2).

J. Liq. Chromatogr. Relat. Technol. 41, 73-82 (2018). Review of the applications of TLC for the analysis of both synthetic and natural sunscreens. The review contained a detailed description of techniques, materials and instruments of selected applications, including laboratory experiments for students, lipophilicity measurements, TLC-bioactivity detection, TLC-MS, separation and characterization of sunscreens, densitometric analysis of formulations, preparative layer chromatography, thin-layer radiochromatography, TLC of decomposition products and study of blood-barrier permeability. Future prospects were also discussed, including TLC–MS for sunscreen analysis.

J. Planar Chromatogr. 11, 94-99 (1998). Optimization of the mobile phase composition in HPTLC for rapid and economic determination of synthetic red pigments in cosmetics and medicines by use of the prisma systems and the super modified simplex (SMS) method. - HPTLC of six red pigments, C. I. 15850 pigment Red57, C. I. 15585 Red53 (Na), C. I. 15630 pigment Red49 (Na), C. I.15800 pigment Red64, C. I. 15880 pigment Red63 (Ca), and C. I. 15865 pigment Red48 on silica. Elution A) with butanol - formic acid 100:1; B) ethyl acetate, and C) tetrahydrofuran - water 9: 1. Optimum for prisma method A - B - C 50: 50: 99 and for SMS method A - B - C 50:72:103. Densitometry at 500 nm.

Pharmazie 62, 803-812 (2007). TLC of anthocyanins in aronia, blueberry and lingonberry extracts and the respective preparations (e.g. capsules, lozenges, granulate) on silica gel with ethyl acetate - water - anhydrous formic acid 10:3:2 and 10:4:1. Detection in white light prior and after spraying with iron(III)chloride solution or with vanillin phosphoric acid reagent.