J. Ethnopharmacol. 317, 116861 (2023). Taxonomic revision of Saraca asoca from ancient times to the present, pharmacological activities and TLC and HPTLC methods for the isolation and identification of different compounds, including alkenes, coenzymes, fatty acids, flavonoids, phenolic acid, phenols, phytosterol, polyphenol and sterols.

J. Ethnopharmacol. 317, 116732 (2023). HPTLC fingerprinting of stem bark of Berberis aristata on silica gel with n-butanol - glacial acetic acid - water 13:3:4. Detection under UV light at 366 nm. The method revealed a major zone at hRf value of 60.

Phytochem. Anal. doi:10.1002/pca.3252 (2023). HPTLC of tripterpenes in the roots of Cecropia angustifolia on silica gel with toluene - chloroform - ethanol 4:4:1. Detection by spraying with vanillin–sulfuric acid reagent. Further analysis by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry.

Phytochem. Anal. doi:10.1002/pca.3265 (2023). HPTLC of antidiabetic compounds in the leaves of Annona cherimola on silica gel with chloroform - propanol - ethyl acetate 21:2:2. Detection of α-amylase inhibitors by spraying with 4 mL of an enzyme solution (6 U/mL) in acetate buffer (0.5 M, pH 6.9), followed by incubation at 37 °C for 10 min, dipping into a 1 % starch solution for 3 s and incubation at 37 °C for 15 min. Inhibitory zones were detected by dipping into a Gram's iodine solution. Detection of α-glucosidase by spraying with 4 mL enzymatic solution (5 U/mL α-glucosidase in phosphate buffer), followed by incubation at 37 °C for 10 min. The enzyme cleaved the substrate producing α-naphthol, which was detected by spraying with 4 mL of an aqueous solution of Fast Blue B salt. Further analysis of active zones by UHPLC-DAD coupled with detector electrospray ionisation tandem mass spectrometry (ESI-MS/MS).

J Pharmacogn Phytochem, 12(1), 159-167 (2023). TLC of methanolic Soxhlet extracts on silica gel with toluene – ethyl acetate – formic acid 16:4:1. Visualization under UV 254 nm and 366 nm. Two bands only (hRF values 10 and 45), observed with densitometric scanning at UV 366 nm, were present in Trianthema portulacastrum roots (Aizoaceae), whereas a different profile was observed with Boerhavia diffusa roots (Nyctaginaceae), which is sometimes substituted for T. portulacastrum.

J. Liq. Chromatogr. Relat. Technol. 45, 100-106 (2022). HPTLC of metformin (1), pioglitazone (2), glipizide (3), and glimepiride (4) in herbal as well as dietary supplements on silica gel with cyclohexane - dichloromethane - 1-propanol - saturated solution of ammonium acetate in acetic acid 7:5:2:2. Quantitative determination by absorbance measurement at 254 nm. The hRF values for (1) to (4) were 26, 46, 55 and 79. Linearity was in the range of 200-1200 ng/zone for (1) to (4). Intermediate precisions were below 10 % (n=9). LOD and LOQ were 186 and 565 ng/zone for (1), 192 and 581 ng/zone for (2), 154 and 465 ng/zone for (3) and 222 and 674 ng/zone for (4), respectively. Recovery was between 97.4 and 105.4 % for (1), 98.2 and 105.4 % for (2), 100.2 and 103.1 % for (3) and 98.8 and 104.4 % for (4).  

J Pharm Bioallied Sci 15(Suppl.2), S948-S951 (2023). Sample was the ethyl acetate fraction of an ethanolic extract of Viola odorata aerial parts (Violaceae). Standards were coumarinic compounds: esculetin (1) and umbelliferone (2). TLC and HPTLC on silica gel with toluene – ethyl acetate – formic acid 5:4:1. Visualization under UV 254 nm and 366 nm; densitometric scanning at 366 nm. Both (1) and (2) were found in the extract (hRF values 30 and 53, respectively, in TLC). Alternative mobile phases were also tested (TLC only): toluene – ethyl acetate 1:1 (hRF values 47 and 68) and chloroform – methanol 97:3 (hRF values 20 and 41).

 J. Pharmacogn. Phytochem. 12(1), 6-14 (2023). TLC silica gel layers were used to monitor the purification through column chromatography (CC) of a chloroform fraction of the methanolic root bark extract of Rauvolfia vomitoria (Apocynaceae). Mobile phases were petroleum ether – ethyl acetate 4:1 (MP1), dichloromethane – methanol 20:1 (MP2), and dichloromethane – methanol 15:1 (MP3). Visualization under UV 254 nm. Preparative TLC on thicker silica gel was performed on two subfractions: (A) with dichloromethane – methanol 100:7 for the isolation of the methyl esters of eudesmic acid and of trimethoxycinnamic acid (hRF values 35 and 28, respectively, in MP1); (B) with MP2 for the isolation of an indole alkaloid: kumujan B (= 1-carbomethoxy-β-carboline, hRF value 40 in MP2). Other indole alkaloids were isolated through CC: ajmaline, mauensine and reserpine (hRF values 35, 13 and 47, respectively, in MP3).