J. Chromatogr. A 1218 (19), 2775-2784 (2011). A multi-enzyme inhibition assay (HPTLC-EI) based on rabbit-liver esterase (RLE) and cutinase following HPTLC allows detection of thiophosphate pesticides. Because choline esterase inhibition is more effective after conversion of thiophosphate thions into their corresponding oxons, a pre-oxidation step was added to the HPTLC-EI assay by using bromine vapor. Bromine was more effective than iodine or UV irradiation for oxidation. It increased the inhibitory strength of parathion, parathion-methyl, chlorpyrifos, chlorpyrifos-methyl, and malathion by 2 orders of magnitude. In contrast, bromine oxidation of organophosphate and carbamate insecticides resulted in a slight reduction in their inhibition factors, due to partial bromination and degradation of the parent compounds. Bromine oxidation increased the inhibition factors for demeton-S-methyl and propoxur. The HPTLC-EI system was applied to the analysis of apple juice and water samples spiked with paraoxon (0.001 mg/L), parathion (0.05 mg/L), and chlorpyrifos (0.5 mg/L) and the mean recoveries were 95-106 % and 91- 102% for RLE and cutinase, respectively.

CBS 108, 4-5 (2012). HPTLC of human insulin recombinant and porcine and bovine pancreas insulin on ProteoChrom silica gel with 2-butanol - pyridine - 25 % ammonia - water 39:34:10:26 to 50 mm migration distance. Detection under UV 366 nm after spraying with 0.02 % fluorescamine in acetone. Elution with the TLC-MS Interface and MS analysis in ESI positive mode, the eluent was acetonitrile - water 1:1. The hRf value of human, porcine and bovine insulin was 50. All mass spectra could be clearly assigned to the different insulin samples.

Journal of Ethnopharmacology 163, 192-202 (2015). TLC of the aqueous extract (crude vs. after tannin removal on a polyamide column) of the kino (red hydrosoluble exudate) of Pterocarpus erinaceus on silica gel with s-butanol – water – acetic acid 14:5:5. Detection with vanillin-hydrochloric acid reagent revealed catechic tannins and related polyphenols as dark pink zones. These compounds showed hRfs between 0 and 40, and above 60 in the case of the crude extract, whereas they almost did not appear in the tannin-free fraction. The extracts were also submitted to HPLC-HRMS, allowing the identification of epicatechin monomer in both extracts and of oligomers in the crude extract only.

CBS 113, 13-15 (2014). HPTLC of glycosylceramide Glc-d18:2 h16:0 from wheat germ and standards squalene, cholesteryl oleate, glyceryl trioleate, linoleic acid, ß-sitosterol, and ß-sitosterol glucoside on silica gel in the AMD 2 with a 18-step gradient modified from Opitz et al. (Chromatographia 73 (2011) 559), methanol replaced ethanol, and the mobile phase composition was changed slightly (pre-conditioning with 4 M acetic acid before each step, drying time 1.5 min, development duration 3 h and solvent consumption 200 mL). Detection by dipping in copper sulfate phosphoric acid reagent for 20 s and heating at 130 °C for 15 min revealed grey-brown bands. Densitometry evaluation by absorbance measurement at 546 nm. For Glc-d18:2 h16:0, regression analysis showed a polynomial relationship with coefficients of determination (R2) from 0.995 to 0.999 (n=3, 50 - 1000 ng/band). LOD (S/N 3) and LOQ (S/N 10) of Glc-d18:2_x000D_ h16:0 were 10 ng/band and 50 ng/band, respectively (n = 6).

Planta Medica 83(01/02), 104-110 (2017). TLC on silica gel 1) to monitor the column fractionation of the chloroform partition of a methanolic maceration of Caesalpinia pulcherrima roots (eluent not given); and for preparative isolation of 2) 8,9,11,14-didehydrovouacapen-5α-ol from a subfraction of the same (with n-hexane – dichloromethane – acetonitrile 50:50:1); 3) pulcherrimin E from another subfraction (with chloroform – methanol 49:1, followed by preparative HPLC); and 4) 6β-cinnamoyl-7β-acetoxyvouacapen-5α-ol and pulcherrimin D, obtained by acetylation (in pyridine and acetic anhydride) from cinnamoyl-7β-hydroxyvouacapen-5α-ol and pulcherrimin A, respectively (eluent not given). Detection by spraying with cerium sulfate and by exposure to iodine vapor._x000D_
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J. Planar Chromatogr. 30, 429-439 (2017). HPTLC of physalin L in orange husks of Physalis alkekengi L. var. franchetii on silica gel with ethyl acetate – n-hexane 3:2. Detection by dipping into 2.5 % (v/v) sulfuric acid in ethanol. Qualitative determination under UV 366 nm. The hRF values for physalin L and its impurity were 61 and 51, respectively, as determined by HPTLC-MS.

J. AOAC Int. 73, 270-275 (1990). TLC of zearalenone, a-zearalenol and ß-zearalenol on silica with chloroform – ethanol 97:3, detection under UV, by spraying with aluminium chloride (20 % in ethanol ) and re-examination under long-wave UV. TLC of trichothecenes (T-2 toxin, HT-2 toxin, nivalenol, fusarenon-X, neosolaniol, and deoxynivalenol) on silica with chloroform – acetone 3:2. After drying detection by spraying with 4-(p-nitrobenzyl)pyrindine, heating at 150 °C for 30 min., cooling and spraying with tetraethylenepentamine solution. New sensitive HPTLC method.

J. Planar Chromatogr. 3, 273-275 (1990). One- and two-dimensional TLC on silica, partly impregnated with a saturated solution of silver nitrate in 90% methanol. One-dimensional: chloroform as eluent; two-dimensional: first dimension twice with chloroform, second dimension with hexane - ether 81:1 with chamber saturation. Detection by spraying with a solution of 5 % phosphomolybdic acid in a mixture of hydrochloric acid (approx. 3.5%) in 2-propanol, followed by heating at 80 °C for 5 min. Also spraying with a copper sulfate-phosphoric acid reagent or a vanillin - sulfuric acid reagent.