Pharmacogn. Mag. 15, 462-467 (2019). HPTLC of diosgenin in the rhizome of Costus speciosus on silica gel with n‑hexane - ethyl acetate 7:2. Detection by spraying with anisaldehyde‑sulfuric acid reagent. Quantitative determination by absorbance measurement at 440 nm. The hRF value for diosgenin was 23. Linearity was between 10 and 90 ng/zone. Intermediate precisions were below 5 % (n=2). The LOD and LOQ were 907 and 2751 ng/zone, respectively. Mean recovery was 100.3 %.

J. Sep. Sci. 43, 1195-1202 (2020). HPTLC of norfloxacin (1) and tinidazole (2) on RP silica gel with 30 % trifluoroacetic acid. Detection under UV 254 and 366 nm, documentation with a smartphone camera. The hR_F values for (1) and (2) were 6 and 31, respectively. Linearity was between 0.06 and 6 µg/zone for (1) and 0.09 and 9 µg/zone for (2). Intermediate precisions were below 2 % (n=3). The LOD and LOQ were 0.01 and 0.03 µg/zone for both (1) and (2).

J. Sep. Sci. 43, 2228-2239 (2020). HPTLC of binary mixtures of tenofivir disoprixil fumarate (1) / lamivudine (2) and lamivudine (2) / zidovudine (3) on silica gel with dichloromethane - acetonitrile - methanol - ammonia 67:20:10:3. Quantitative determination by absorbance measurement at 272 nm. The hR_F values for (1) to (3) were 43. 79 and 81, respectively. Linearity was in the range of 5-40 µg/mL for (1), 2-16 µg/mL for (2) and 1-16 µg/mL for (3). Intermediate precisions were below 2 % (n=3). The LOD and LOQ were 1 and 3 µg/mL for (1), 1 and 4 µg/mL for (2) and 2 and 6 µg/mL for (3), respectively. Recovery was between 96.5 and 101.8 % for (1) to (3).

J. Sep. Sci. 43, 1566-1575 (2020). HPTLC of phenyl myristate in the bark and leaves of Homalium nepalense on silica gel with chloroform - methanol 9:1. Quantitative determination by absorbance measurement at 254 nm. The hR_F value for phenyl myristate was 49. Linearity was in the range of 100-500 ng/5 µL. Intermediate precisions were below 1 % (n=5). The LOD and LOQ were 3 and 10 ng/5 µL, respectively. Average recovery was  between 90.1 and 95.6 %.

J. Sep. Sci. 43, 2330-2337 (2020). HPTLC of metoclopramide (1), ergotamine (2), caffeine (3), and paracetamol (4) on silica gel with ethyl acetate - ethanol - ammonia 90:10:1. Quantitative determination by absorbance measurement at 272 nm. The hR_F values for (1) to (4) were 14, 36, 49 and 74, respectively. Linearity was in the range of 1-24 µg/zone for (1), 0.1-6.5 µg/zone for (2), 0.8-3.5 µg/zone for (3) and 0.8-10 µg/zone for (4), respectively. Intermediate precisions were below 2 % (n=9). The LOD and LOQ were 336 and 1017 ng/zone for (1), 43 and 130 ng/zone for (2), 265 and 802 ng/zone for (3) and 262 and 793 ng/zone for (4). Average recovery was 99.7 % for (1), 100.6 % for (2), 100.1 % for (3) and 100.2 % for (4).

Phytochem. Anal. 31, 57-67 (2019). HPTLC of gymnemagenin in the leaves of Gymnema sylvestre on silica gel with toluene - chloroform - methanol 5:8:3. Detection by spraying with vanillin sulphuric acid reagent, followed by heating at 110 ºC for 5 min. Quantitative determination by absorbance measurement at 610 nm. The hR_F value for gymnemagenin was 37. Linearity was between 400 and 3000 ng. The LOD and LOQ were 68 and 206 ng, respectively.

J. Liq. Chromatogr. Relat. Technol. 43, 351-360 (2020). HPTLC of colchicine (1) and gloriosine (2) in Gloriosa superba on silica gel with chloroform - acetone - di-ethylamine 5:4:1. Quantitative determination by absorbance measurement at 350 nm. The hR_F values for (1) and (2) were 50 and 40, respectively.  The study promotes the use of G. superba as an adjuvant therapy in gouty arthritis and helps explore the elite chemotype(s) with validated pharmacological action to meet out the medicinal and commercial demands.

J. Liq. Chromatogr. Relat. Technol. 43, 414-423 (2020). HPTLC fingerprint of Ganoderma lucidum fruiting body on silica gel with toluene - tetrahydrofuran - acetic acid 70:30:1. Detection by dipping into a solution of 10% sulfuric acid in methanol, followed by heating at 100 ºC for 3 min. Qualitative determination under UV light at 254 and 366 nm. The hRF values for ganoderic acids D, B, A, G and C2 were in the zone between 10 and 50. This zone was used for quantification of total triterpene acids by absorbance measurement at 260 nm. Linearity of each of the main peaks between hRF 10 to 50 was determined. The linear range of ganoderic acid A was between 200 and 500 ng/zone.  The study proposes a new method for evaluation, based on “comprehensive high-performance thin layer chromatography (HPTLC) fingerprinting.” Instead of several different methods using different chromatographic techniques, a single HPTLC analysis for identification of Ganoderma lucidum fruiting body with a test for adulteration and quantitative determination of the content of total triterpene acids is proposed. As an alternative to the current tests in the  USP monograph on G. lucidum fruiting body this HPTLC method is a single, low-cost test, which eliminates the UHPLC assay of total triterpene acids.