Trends Anal. Chem. 157, 116828 (2022). Review of the analysis of drugs of abuse in exhaled breath. The paper described sampling devices, sample pretreatment techniques and the application of chromatographic techniques, including TLC for the analysis of drugs of abuse.

Marine Drugs 19(3), 161 (2021). Samples were a standard mix (tripalmitin, palmitic acid, cholesterol, phosphatidylcholine) and lipid-enriched extracts of zebrafish larvae (Danio rerio, Cyprinidae), that were anesthetized with tricaine after having being treated with 11 extracts of cyanobacteria strains and/or with a green fluorescent lipid analogue of fatty acids (BODIPY-C16, bore-dipyrromethene derivative). HPTLC on nano silica gel in 3 steps: 1) and 2) with chloroform – methanol – water 12:6:1 (twice up to 4 cm); 3) hexane – diethyl ether – acetic acid 160:40:3 (once up to 9 cm). Derivatization of lipids by spraying primuline solution (0.01 % in acetone – water, 3:2). Quantification based on fluorescence peak area intensity, was performed using image software on pictures taken through a green fluorescence imager. Triglycerides were decreased in the case of larvae treated with 2 extracts of Synechocystis strains (Merismopediaceae), but the levels of other lipid classes were not affected. No treatment significantly affected the incorporation of BODIPY-C16 into any of the lipid classes of the larvae.

Food Chem. 408, 135253 (2023). HPTLC of genotoxic compound zones in 33 oils on silica gel with chloroform - ethanol 5:1, up to 20 mm, then with n-hexane - diethyl ether 2:1, up to 40 mm, and finally with n-hexane - toluene 1:2 up to 60 mm. Detection in white light, UV 254 nm and 366 nm. Genotoxicity bioassay by spraying with Salmonella suspension with or without the S9 mixture (fraction from phenobarbital/β-naphthoflavone-induced lyophilized rat liver strain), followed by incubation at 37 °C for 3 h. The plate was dried and FDG (fluorescein di(β-D-galactopyranoside)) was sprayed, followed by incubation at 37 °C for 15 min. Cytotoxicity bioassay by spraying with MTT solution (0.2 % in phosphate buffer) after incubation with the Salmonella culture, followed by analysis under white light. Confirmative detection of aliphates was performed via a reagent sequence on the same plate by spraying with 1) Rhodamine 6B reagent, followed by detection in UV 366 nm and 2) phosphomolybdic acid reagent, followed by heating at 120 °C for 10 min, and documented at white light illumination.

J Chromatogr A, 1684, 463582 (2022). Samples were concentrated filtrates of leachates of waste deposition sites, as well as testosterone, flutamide, bisphenol A (BPA) and nitroquinoline oxide (NQO) as standards. Automated Multiple Development on HPTLC silica gel (prewashed with methanol and dried 30 min at 110 °C) with 1) methanol up to 20 mm; 2A) chloroform – ethyl acetate –petroleum ether 11:4:5 or 2B) ethyl acetate – n-hexane 1:1 for flutamide and testosterone, up to 90 mm. Effect-directed analysis was performed by automated spraying 3 mL suspension of BJ1991 yeast (transfected Saccharomyces cerevisiae strain, pure for androgenic activity, with 50 ng/mL testosterone for anti-androgenic assay), followed by 20 h incubation at 30 °C in a closed chamber (90 % relative humidity), by 5 min drying under cold air stream, by spraying 2.5 mL MUG solution (4-methylumbelliferyl-galactopyranoside) and by 15 min incubation at 37 °C in an open chamber. Agonistic and antagonistic activities were detected qualitatively under UV 366 nm (light or dark blue bands, respectively, on blue background) and quantitatively documented using automated scanning at excitation wavelength 320 nm (deuterium lamp), with cut-off filter at 400 nm. Dose-response curves for model compounds were established by regression analysis. Anti-androgenic effective doses at 10 % were 28 ng/zone for flutamide and 20 ng/zone for BPA, without toxicity for the yeast. To exclude cytotoxicity where anti-androgenic activity was observed, the HPTLC layers (either without or after the spraying with MUG) were sprayed with 3 mL resazurin solution (0.01 % in water) and incubated 30 min at 30 °C and 90 % humidity. Cytotoxicity bands appeared as pink zones of resorufin on a colorless background (dihydroresorufin) under white light. Densitometric evaluation in absorption mode at 575 nm (under deuterium and halogen-tungsten lamps, no filter applied). NQO was cytotoxic at its lowest tested dose (1 ng/zone).

J. Planar Chromatogr. 35, 543-546 (2022). HPTLC of diazepam in spiked lemon juice drink on silica gel with chloroform - acetone 4:1 (system 1) and chloroform - methanol - ethyl acetate 14:3:1 (system 2). Detection under UV light at 254 nm. The hRF values for diazepam in systems 1 and 2 were 72 and 88, respectively. 

J. Planar Chromatogr. 35, 363-373 (2022). HPTLC of midazolam (1), prochlorperazine (2), citalopram (3) and chlorodiazepoxide (4) in urine on silica gel with cyclohexane - toluene - diethylamine 14:3:3. Quantitative determination by absorbance measurement at 229 nm for (1), 257 nm for (2), 240 nm for (3) and 275 nm for (4). The hRF values for (1) to (4) were 31, 79, 63 and 7, respectively. Linearity was between 3 and 7 µg/zone for (1) to (4). Interday and intra-day precisions were below 5 % (n=3). The LOD and LOQ were 0.5 and 1.6 µg/zone for (1), 0.7 and 2.1 µg/zone for (2), 0.5 and 1.6 µg/zone for (3) and (4).  Average recovery was 95.5 % for (1), 90.5 % for (2), 95.9 % for (3) and 92.5 % for (4).

Chinese J. Food & Drug 23 (3), 229-232 (2021). Non-benzodiazepines are inhibitors directly acting in the central nervous system, with sedative, anxiolytic and anticonvulsant effects. They are used as third generation sedative-hypnotic drugs to treat insomnia. However, it has been found that they are illegally added to some health foods on the market, which may cause long-term abuse and cause harm to the human body. Therefore, it is necessary to strenghten a rapid screening to detect the illegal addition of non-benzodiazepines to health foods, to improve the efficiency of supervision, and to crack down illegal practices.  TLC of ethyl acetate extracts of health foods adulterated with non-benzodiazepines, on silica gel with dichloromethane - methanol - ethyl acetate 17:2:6. Detection in UV 254 nm, identification by fingerprint comparison with the standards zolpidem, zalepron and zoppilon. Using this method, 65 batches of health food samples obtained from the market were screened, and four of them were suspected of illegal addition of zopiclone. This result is consistent with the analysis using both HPLC-DAD and HPLC-MS, and proved the  TLC method to be simple, fast, accurate, easy to operate, and well suitable for quick screening.

ALTEX - Alternatives to animal experimentation, 38(3), 387-397 (2021). Samples were standards of food contact contaminants with genotoxicity (4-nitroquinoline-1-oxide (NQO), aflatoxin B1, hexachloroethane, nitroso-ethylurea, phenformin, PhIP) or negative controls (alosetron, mannitol), and extracts of coated tin cans (extracted with n-hexane – acetone at 25°C for 16 h or by heating at 60 °C with ethanol 95 % for 240 h). HPTLC on RP18W layer, pretreated to harden the binder by heating 1 h at 120 °C, prewashed with methanol and with ethyl acetate and dried 4 min in cold air stream after each development. Application areas were focused to their upper edges by a two-fold elution with ethyl acetate, followed by 1 min drying in cold air stream. Development with toluene – ethyl acetate 8:5, followed by 5 min drying, neutralization with citrate buffer (pH 12) and 4 min drying. Effect-directed analysis for genotoxicity (SOS response – UMU-C test, using NQO as positive control) by immersion (speed 3.5 cm/s, time 3 s) into Salmonella typhimurium suspension and, after 3 h incubation at 37 °C and 4 min drying in cold air stream, into one of two fluorogenic substrate solutions (methylumbelliferyl- vs. resorufin-galactopyranoside). After 1 h incubation at 37 °C, visualization of mutagenic compounds as (blue vs. red) fluorescent zones at FLD 366 nm, and densitometry performed with mercury lamp for fluorescence (at  366 / >400nm vs. 550 / >580 nm, respectively). Further validation experiments, including spiking extracts with NQO, were performed showing good mean reproducibility, no quenching or other matrix effects. Lowest effective concentration of NQO was 0.53 nM (20 pg/band), 176 times lower than in the corresponding microtiter plate assays.