J. Ethnopharmacol. 202, 97-102 (2017). HPTLC of betaine in the roots of Achyranthes aspera on silica gel with methanol – water 9:1. Detection by spraying with Dragendorff's reagent, followed by 10 % ethanolic sulfuric acid and drying at 110 °C for 5 min. Quantitative determination by densitometry at 520 nm. The hRF value for betaine was 36. Linearity was between 1 and 5 μg/band. The intermediate precision was below 2 % (n=6). LOD and LOQ were 0.13 μg/mL and 0.10 μg/mL, respectively. (Note: The reported LOD and LOQ do not make sense, as LOD is higher than LOQ.)

J. Planar Chromatogr. 30, 307-312 (2017). HPTLC of artesunate (1) and amodiaquine (2) on silica gel with toluene – acetonitrile – methanol – ammonium acetate – triethylamine 20:10:6:2:1. Detection of (1) by spraying with a mixture of methanol and sulfuric acid 19:1, followed by heating at 75 °C for 5 min. Quantitative determination by absorbance measurement at 503 nm for (1) and 345 nm for (2). The hRF values for (1) and (2) were 35 and 68, respectively. Linearity was between 93 and 280 ng/zone for (1) and 250 and 1250 ng/zone for (2). The intermediate precision (n=6) was <5 % for (1) and 2 % for (2). Recovery rate ranged from 90 to 110 % for (1) and from 98 to 102 % for (2).

J. Planar Chromatogr. 30, 299-306 (2017). HPTLC of itopride (1), pantoprazole (2), and mosapride (3) in human plasma on silica gel with methylene chloride ‒ ethyl acetate ‒ methanol ‒ 25 % ammonia 60:10:4:1. Quantitative determination by absorbance measurement at 289 nm. The hRF values for (1), (2) and (3) were 22, 41 and 62, respectively. Linearity was between 100 and 1500 ng/zone for (1) and (3), and between 70 and 1500 ng/zone for (2). The intermediate precision (n=3) was <2 % for (1) to (3). LOD and LOQ were 33 and 98 ng/mL for (1), 17 and 51 ng/mL for (2) and 30 and 91 ng/mL for (3). Average recovery rate was 99.2 % for (1), 99.1 % for (2) and 99.6 % for (3).

J. Chromatogr. A 1515, 232-244 (2017). Characterization of lipids in both bone marrow (BM) and mineralized tissue (MT) compartments, and their potential implication in bone pathologies, involving sample preparation, lipid extraction and analytical issues using a small sample size (≤ 0.5 g of rat femurs). Two major issues in bone handling were addressed with two cleaning steps after BM removal and by adding a demineralization step to the overall lipid extraction protocol, to avoid potential contamination of the MT by marrow lipids and the poor accessibility of certain lipids from the MT. HPTLC of the major neutral and polar lipids provided excellent resolution for 15 standards, good precision (inter-day %RSD <13 %) and recoveries of the standards ranged between 76 and 122 %. The method was suitable for lipid determination in both BM and MT and reliable in terms of lipid quantification. Demineralization facilitates phosphatidylserine and cholesterol ester extractions from the MT. Confirmation of the HPTLC data by HPLC determination of fatty acids as naphthacyl esters in bone samples. The mineralized tissue seems to be more metabolically active than the bone marrow.

J. Planar Chromatogr. 30, 418-422 (2017). HPTLC-DPPH* assay of instant gruels enriched with cranberry fruits on silica gel with acetonitrile – water – chloroform – formic acid 30:2:5:2. Detection by dipping into a freshly prepared 0.1 % methanolic 2,2-diphenyl-1-picrylhydrazyl (DPPH*) solution. The plate was scanned with a flat-bed scanner every minute over an hour. The area of the standard solution of rutin at the concentration of 0.5 mg/mL was adopted as the reference point.

J. Agric. Food Chem. 65, 8683-8690 (2017). HPTLC of fatty acid alkyl esters and free fatty acids in a transesterification reaction on silica gel with copper sulfate – phosphoric acid – methanol – water 10:8:5:78, followed by heating at 180 °C for 10 min. Quantitative determination by absorbance measurement at 550 nm.

J. Planar Chromatogr. 31, 7-12 (2018). HPTLC of L-histidine (1), L-glycine (2), L-alanine (3) an L-phenylalanine (4) in Steatoda grossa spider web on silica gel with 2-butanol – acetone – glacial acetic acid – water 7:7:2:4. Detection by spraying with 0.5 % solution of ninhydrin in methanol, followed by heating at 100–110 °C for 10 min. Quantitative determination by absorbance measurement at 500 nm. The hRF values for (1) to (4) were 11, 35, 48 and 72, respectively. Linearity was between 0.2 and 1.0 μg/zone for (1) and (2), 0.1 and 0.5 μg/zone for (3) and 0.3 and 1.5 μg/zone for (4). LOD and LOQ were 185 and 556 ng/zone for (1), 154 and 461 ng/zone for (2), 100 and 302 ng/zone for (3) and 152 and 456 ng/zone for (4).

CBS 118, 9-12 (2017). Comparison of TLC and HPTLC methods for (1) an aqueous-ethanolic extract of kidney vetch, (2) suppositories containing caraway extract, aqueously fermented root extracts of (3) barberry and (4) Solomon’s seal, and standards quinine hydrochloride, hyperoside, caffeic acid, rutin, fructose, caffeic acid, and noscapine hydrochloride. HPTLC on silica gel for (1) with chloroform – methanol – water 14:6:1, (2) with ethyl acetate – anhydrous formic acid – water 21:2:2, (3) with ethyl acetate – anhydrous formic acid – water 8:1:1 and (4) with chloroform – methanol – water 25:21:4. Detection by spraying with a (1) solution of 20 % antimony(III) chloride in chloroform and heating at 105 °C for 30 min, (2) 1 % methanolic solution of diphenylborinic acid 2-aminoethyl ester (natural products reagent), followed by a 5 % methanolic polyethylene glycol (macrogol) 400 solution and detection at UV 366 nm after 30 min, (3) bismuthate reagent (mixture of 0.85 g alkaline bismuth nitrate, 40 mL water, 10 mL acetic acid, and 20 mL potassium iodide solution (400 g/L), glacial acetic acid and water, 1:2:10), and (4) 1:1 mixture of 5 % sulfuric acid in ethanol and 2 % vanillin in ethanol and heating for 15 min at 105 °C. Compared to TLC, by HPTLC developing times were decreased, the separation power was higher and zones were sharper.