Chin J Anal Sci 38 (4), 433-440 (2022). TLC of acetochlor, alachlor, metolachlor, butachlor and pretilachlor in the root vegetables onion and garlic on silica gel with hexane – acetone 4:1. Detection by spraying with 5 % iodized bismuth potassium in acidic aqueous solution. Then QuEChERS (quick, easy, cheap, effective, rugged, safe)-GC-MS/MS method in the selected ion monitoring mode for determination of residues of these compounds after extraction with acetonitrile and acetonitrile - acetic acid and purification by PSA , MWCNTs , GCB and C18 at optimized conditions. The linearity ranged from 0.02 to 2.0 μg/mL for the 5 compounds with the correlation coefficients greater than 0.99, the LOQ was 0.025 mg/ kg, the average recoveries ranged from 72.0 % to 102 % with the relative standard deviations from 0.5 % to 7.9 %.

Front. Nutr. 9, 887992 (2022). HPTLC of 13 mogrosides, 1 flavonoid, and 3 sugars in monk fruit products on silica gel with n-butanol - water - ethanol - acetic acid 70:10:10:2. Detection by spraying with 10 % sulfuric acid in ethanol solution, followed by heating at 105 °C for 10 min. Orthogonal partial least square-discriminant analysis (OPLS-DA) was subsequently conducted allowing the identification mogroside V, 11-oxo-mogroside V, isomogroside V, mogroside IV and sucrose to be the characteristic compounds to distinguish the two types of monk fruits.

Food Chem. DOI: 10.1111/1750-3841.16708 (2023). HPTLC of phenylpropanoids in the leaves of Ginkgo biloba on silica gel with dichloromethane - ethyl acetate 1:1. Detection by spraying with 10 % sulfuric acid ethanol solution, followed by heating. Qualitative identification under UV light at 366 nm. Further analysis by nuclear magnetic resonance. The method allowed the identification of phenylpropanoids suitable for controlling foodborne pathogens.

Anal. Bioanal. Chem. https://doi.org/10.1007/s00216-023-04605-x (2023). HPTLC of 60 pesticides (1), six plant protection products (2), tomato (3) and grape and wine samples (4) on silica gel with n-hexane - ethyl acetate 5:1, n-hexane - toluene - ethyl acetate 4:1:1 for (2), n-hexane - toluene - ethyl acetate 5:1:1 for (3) and n-hexane - ethyl acetate 5:1 for (4). Documentation in fluorescence mode at 366 nm. pYES bioassay application by dipping into a citrate phosphate buffer, followed by drying and dipping into yeast cell suspension, followed by incubation at 30 °C for 3 h. After drying, the chromatogram was immersed into a MUG solution, followed by incubation at 37 °C for 1 h. Detection at FLD 366 nm/ > 400 nm.

Phytochem. Anal. doi:10.1002/pca.3230 (2023). HPTLC of quercetin (1), caffeic acid (2), gallic acid (3) and ferulic acid (4) in three black rice varieties from Northeast India on silica gel with toluene - ethyl acetate - formic acid 7:2:1. Quantitative determination by absorbance measurement at 254 nm. The hRF values for (1) to (4) were 60, 55, 37 and 68, respectively. Linearity was in the range of 0.2-1 µg/zone for (1) to (4). Intermediate precisions were below 2 % (n=3). Mean recovery was 99.5 % for (1) to (4).

Food Res. Int. 173, 113288 (2023). Review of production, bio-activity, and the role of coffee oligosaccharides (COS) as a functional food, including TLC and HPTLC separation and characterization techniques for the analysis of COS.

Food Chem. 416, 135822 (2023). A chip consisting of two parts: a pesticide residue reaction and a separation area cut from a TLC plate was used for the analysis of pesticides dichlorvos, paraoxon and parathion in spiked cabbage, cucumber and spinach with 40 % dd water - acetonitrile solution. Once the pesticide was absorbed by the pesticide enrichment zone, the TLC plate was removed and allowed to dry in the air for 1 min, followed by adding the esterase enzyme solution (prepared from crushed malted barley) and incubation at 37 °C for 3 min. Detection by overlapping with a substrate cromogenic area impregnated with dichloroindophenol acetate. A scanner and digital image-processing was performed to quantify adsorbed substances. LOD was 2 ng/g for dichlorvos, 6 ng/g for paraoxon, and 3 ng/g for parathion.

J. Liq. Chromatogr. Relat. Technol. doi.org/10.1080/10826076.2023.222402445 (2023). HPTLC of polyphenolic compounds in seven different types of monofloral honey on silica gel with methanol - water - formic acid 50:50:1. Detection by heating at 100 °C for 3 min, followed by dipping into NP solution (1 g NP in 200 mL ethyl acetate), drying in cold air and dipping into PEG solution (10 g of PEG in 200mL dichloromethane). Detection under UV light at 254 and 366 nm. The methods allowed discriminating between honeys of different floral origin and also of different source for their authentication.