J. Planar Chromatogr. 36, 433-438 (2023). HPTLC of synthetic cannabinoids AM2201 (1), CP-47,497 (2), and JWH-018 (3) in seized samples on silica gel with cyclohexane - diethylamine 9:1. Quantitative determination by absorbance measurement at 280 nm for (2) and 315 nm for (1) and (3). The hRF values for (1) to (3) were 26, 73 and 55, respectively. Linearity was between 2 and 14 µg/zone for (3), 5 and 35 µg/zone for (1) and 50 and 350 µg/zone for (2). The intermediate precision was 23.0 % for (1), 16.6 % for (2) and 7.5 % for (3). The LOD and LOQ were 5.6 and 16.9 µg/zone for (1), 0.7 and 2.2 µg/zone for (2) and 1.9 and 5.6 µg/zone for (3). Average recovery was 84.0 % for (1), 105.1 % for (2) and 107.1 % for (3).

J. Ethnopharmacol. 318, 116977 (2024). HPTLC of Oxalis corniculata on silica gel with chloroform - methanol - water 15:3:2. Detection by spraying with 2 % aluminium chloride. Qualitative analysis under UV light at 344 nm. Further analysis by mass spectrometry.

Microbiol. Res. 281, 127602 (2024). Review of potential applications of indole-3-acetic acid (IAA) in optimizing crop yields and fostering environmental resilience, including techniques for the bacterial IAA quantification. TLC and HPTLC methods were described, for the analysis of IAA in the range of 100 to 1000 ng/zone from microbial samples.

PLoS Neglected Tropical Diseases 17(09), e0011646 (2023). Samples were extracts rich in sphingolipids obtained from Trypanosoma cruzi epimastigotes, or from Leishmania major promastigotes (Trypanosomatidae), or from Chlorocebus sp. kidney Vero cells (Cercopithecidae), all cell lines incubated 2h before the extractions with ceramide N-hexanoyl-D-erythro-sphingosine coupled to fluorescent NBD-amine group (NBD = nitrobenzoxadiazolyle). Dried extracts were resuspended in chloroform – methanol (1:1) before application on TLC silica gel layers. Development with chloroform – methanol – potassium chloride 0.25 % aqueous solution 11:9:2. Visualization under automated laser scanner. Three sphingolipids were detected due to the NBD fluorescent group: sphingomyelin (hRF 42) was present in Vero cells only (negative control), whereas the targeted inositol-phosphorylceramide (IPC, hRF 70), was present in both L. major (positive control) and T. cruzi wild-type. It was absent in T. cruzi cell lines knock-out (KO) for the IPC-synthase (IPCS) gene, but present again in the add-back cell-lines (obtained with plasmide transfection of the IPCS gene into KO cells). An unknown lipid (hRF 78) was detected in all T. cruzi samples.

PLoS ONE 18(11), e0294054 (2023). Sample was a pigment extracted with methanol from cell pellets of Serratia marcescens strain BRL41 (Yersiniaceae). TLC on silica gel with ethyl acetate. Detection under daylight. The pink pigment had the same hRF value (87) and colour as prodigiosin from standard strain ATCC-13880.

PLoS ONE 18(11), e0295012 (2023). TLC on silica gel to monitor the synthesis of 15 new camphene-based thiosemicarbazones produced by the reaction of camphene thiosemicarbazide either with benzaldehydes, or with acetophenones, or with one of the following molecules: benzophenone, cinnamic aldehyde, ethyl pyruvate, furaldehyde, menthone, pyrrole carboxaldehyde or thiophene-carboxaldehyde. Development with n-hexane – ethyl acetate 3:7 in the case of benzaldehydes, except vanillin; or 7:3 for the vanillin derivative and all others, followed by visualization of products with resublimated iodine. The aldehyde used for compound 15 is in fact vanillin.

J Chrom Sci, bmad055 (2022). Standards of antiglycemic drugs were metformin hydrochloride (S1, a biguanide), glibenclamide (S2 = glyburide, a sulfonylurea), pioglitazone hydrochloride (S3, a thiazolidinedione), repaglinide (S4, a glinide). Samples were methanolic solutions of commercial tablets of S1 with each of the other molecules. The following method was developed by a software-assisted AQbD approach (analytical quality by design): (1) Several TLC separations were tried with toluene together with other solvents and with acidic or basic modifiers, with also variations of 24 method or instrumental parameters. (2) Principal component analysis (PCA) was performed in order to identify two principal components (PCs) responsible for 98 % of the observed variations: namely, resolution and tailing factor. Three critical method parameters (CMPs) had a statistically significant impact on the PCs: mobile phase (MP) composition, ammonium acetate concentration in MP, and saturation time. (3) To optimize these CMPs, the Box–Behnken design was implemented in 15 software-proposed experiments; the impacts of the 3 CMPs on the 2 PCs were evaluated by ANOVA, multiple regression analysis, and 2D and 3D contour plots. (4) The optimal CMPs ranges were determined by defining a MODR (method operable design region) on the superposed contour plots, and one TLC condition was selected as analytical control point.
TLC on silica gel pre-washed with 10 mL methanol, dried and activated 10 min at 100° C. Separation with toluene – ethyl acetate – methanolic solution of 4 % ammonium acetate 7:7:6 after 15 min pre-saturation with 35 % relative humidity. Absorption emasurement at UV 254 nm. The hRF values were 13 for S1, 72 for S2, 82 for S3, 38 for S4. LOQ were 263, 387, 73 and 35 ng/zone, respectively. Linearity range was 25–75 µg/zone for S1, 100–300 ng/zone for S2 and S4, 750–2250 ng/zone for S3. Intermediate precision was below 2 %. For accuracy tests, recovery rates were between 97.6–101.4 %.

J Chrom Sci, bmad055 (2022). Standards of antiglycemic drugs were metformin hydrochloride (S1, a biguanide), glibenclamide (S2 = glyburide, a sulfonylurea), pioglitazone hydrochloride (S3, a thiazolidinedione), repaglinide (S4, a glinide). Samples were methanolic solutions of commercial tablets of S1 with each of the other molecules. The following method was developed by a software-assisted AQbD approach (analytical quality by design): (1) Several TLC separations were tried with toluene together with other solvents and with acidic or basic modifiers, with also variations of 24 method or instrumental parameters. (2) Principal component analysis (PCA) was performed in order to identify two principal components (PCs) responsible for 98 % of the observed variations: namely, resolution and tailing factor. Three critical method parameters (CMPs) had a statistically significant impact on the PCs: mobile phase (MP) composition, ammonium acetate concentration in MP, and saturation time. (3) To optimize these CMPs, the Box–Behnken design was implemented in 15 software-proposed experiments; the impacts of the 3 CMPs on the 2 PCs were evaluated by ANOVA, multiple regression analysis, and 2D and 3D contour plots. (4) The optimal CMPs ranges were determined by defining a MODR (method operable design region) on the superposed contour plots, and one TLC condition was selected as analytical control point.
TLC on silica gel pre-washed with 10 mL methanol, dried and activated 10 min at 100° C. Separation with toluene – ethyl acetate – methanolic solution of 4 % ammonium acetate 7:7:6 after 15 min pre-saturation with 35 % relative humidity. Absorption emasurement at UV 254 nm. The hRF values were 13 for S1, 72 for S2, 82 for S3, 38 for S4. LOQ were 263, 387, 73 and 35 ng/zone, respectively. Linearity range was 25–75 µg/zone for S1, 100–300 ng/zone for S2 and S4, 750–2250 ng/zone for S3. Intermediate precision was below 2 %. For accuracy tests, recovery rates were between 97.6–101.4 %.