J. Liq. Chromatogr. Relat. Technol. 39, 607-612 (2016). HPTLC of glucose, fructose, xylose, rhamnose, arabinose, and galacturonic acid in Adansonia digitata dry fruit pulp on diol phase with a 15-step gradient based on acetone - acetonitrile 1:1 and water mixtures for enzymatic degradation products. Monosaccharide moieties were separated on silica gel with acetonitrile - acetic acid - water 63:33:5 to a developing distance of 80 mm. Detection by dipping into 10 % sulfuric acid in ethanol. Quantitative determination by absorbance measurement at 400 nm. The hRF values for rhamnose and glucose were 69 and 52, respectively. The HPTLC metehod could rapidly analyze complex mixtures containing a broad variety of monosaccharides that overlapped in a HPLC method.

Food Chem. 233, 290-301 (2017). Review of analytical methods for the effective control of patulin contamination, including TLC validated methodologies. The paper included a reference of standard methods, including the official AOAC method where detection is achieved by spraying with 3-methyl-2-benzothiazolinone hydrazone with a limit of detection of approximately 20 mg/L.

J. Chromatogr. A 1506, 109-119 (2017). HPTLC of seven important steviol glycosides on silica gel, which may degrade in food products under certain processing and storage conditions, and additionally as a sum parameter their reported breakdown products steviol and isosteviol. Detection with 2-naphthol and primuline reagent. Baseline separation of steviol and isosteviol was achieved after a plate cut and subsequent short development (two-step method). The HPTLC method was robust with regard to varying sample matrix loads, provided a high sample throughput (23 separations in parallel on one plate), and was fast (total analysis time of 1 h: 30 min application, 15 min separation and 15 min derivatization/densitometry, leading to 2.6 min per sample). The solvent consumption was low (0.4 mL per analysis) and accuracy of the densitometric quantification was good. Confirmation of the results with HPTLC-ESI-MS of only the zones of interest instead of matrix or background so that there was less need for MS cleaning. Hyphenation to Aliivibrio fischeri bioassay to obtain information on bioactive compounds in Stevia leaf extracts.

J. Chromatogr. A 1533, 208-212 (2018). Development of a rapid method for the determination of caffeine, theobromine and theophylline in Mate beer and Mate soft drinks. Sample preparation through filtration followed by degassing, dilution with acetonitrile in the case of Mate beers for protein precipitation and centrifugation. HPTLC of the extracts on silica gel with acetone – toluene – chloroform 4:3:3, detection and quantification by densitometry at UV 274 nm. The LOD and LOQ were 1 and 4 ng/zone for caffeine, theobromine and theophylline, respectively, and recoveries were close to 100%. Demonstration of the method by applying to the analysis of the concentrations of three methylxanthines in Mate beers as well as Mate beers and Mate soft drinks available from the market proved to be sensitive, accurate and reliable.

J. Chromatogr. A 1569, 212-221 (2018). Presentation of a method for simultaneous determination of mono-, di-, oligo- and polysaccharides in food by HPTLC on silica gel with acetonitrile – water 4:1 containing 3.6 mM natural products reagent A in a single development. Use of the method for both, effective food screening and quantification for up to 20 samples in parallel on the same plate with good reproducibility of the separation at control of the layer activity, and with the determination coefficients of the calibration curves between 0.9980 and 0.9998. Test of the method with 4 different prebiotic food and 60 naturally degraded inulin samples proved its advantages of minimal sample preparation along with the determination of the intact inulin and FOS allowed the evaluation of the natural inulin degradation profile, as shown for naturally degraded inulin samples, and the method is robust and suitable for routine analysis, especially in food control, as well as might be of interest in other fields, e.g. plant breeding, edible insects, functional feed and metabolic processes.

J.A.O.A.C. 67, 513-515 (1984). TLC of aspartame (N-alpha-aspartyl phenylalanine 1-methylester) in dry beverage bases and sweetener tablets on silica with butanol- acetic acid - water 4:1:1. Ninhydrin as spray reagent.

of Medicine Industry 12, 30-31 (1983) (Chinese) (Screening of antibiotics by thin-layer chromatography and bioautography.) TLC of antibiotics on silica with chloroform - methanol - NH3 in different proportions. Detection by overlaying the plate with agarose gel containing neutral red, protein, beef extract, NaCl, glucose and test bacteria, e.g. Escherichia coli, and incubating at 37 °C for 18-24 hr: red bacteria areas and yellow inhibition zones.

J. Agric Food Chem. 33, 1160-1163 (1985). Two-dimensional TLC separation of cis/trans carotene isomers on Ca(OH)2 -layers using 1.5 % p-dimethylanisole in petrolether in each direction (separation in covered tank); identification by comparison of absorption spectra after elution.