J. Sep. Sci. 44, 530-538 (2021). HPTLC of tamsulosin (1) and tadalafil (2) in presence of their degradation products (2) and (3) on silica gel with ethyl acetate - toluene - methanol - ammonia 20:10:20:3. Quantitative determination by absorbance measurement at 280 nm. The hRF values for (1) to (4) were 55, 68, 14 and 24, respectively. Linearity was between 0.5 and 25 µg/zone for (1) and (2). Intermediate precision was below 2 % (n=3). Average recovery was 99.7 % for (1) and 100.3 % for (2).

Pharm. Res. 38, 127-140 (2021). HPTLC of [11C]metoclopramide in plasma, kidney, urine and liver extracts on silica gel with ethyl acetate - ethanol - 25 % ammonium hydroxide 16:4:1. Detection using a multisensitive phosphor screen. The hRF value for [11C]metoclopramide was 60. The method allowed kinetic analysis in different organs after radiotracer injection in mice.

J. AOAC Int. 103, 980-988 (2020). HPTLC of imidocarb dipropionate and its forced induced degradation products in bovine meat and milk on silica gel with ethyl acetate - methanol - ammonia - water 85:10:5:2. Quantitative determination by absorbance measurement at 254 nm. Linearity was between 100 and 1800 ng/zone. Intermediate precision was below 1 % (n=3). The LOD and LOQ were 17 and 52 ng/zone, respectively. Average recovery was 100.8 %. The HPTLC method showed comparable results to a validated HPLC method for resolution and determination of imidocarb in the presence of its degradation products.

J. AOAC Int. 103, 1167-1172 (2020). HPTLC of aminexil (1), niacinamide (2) and pyridoxine HCl (3) on silica gel with propanol - toluene - 33 % ammonia solution
20:30:1. Quantitative determination by absorbance measurement at 270 nm. Linearity was between 0.25 and 1.25 µg/zone for (1), 2 and 7 µg/zone for (2) and 3 and 7 µg/zone for (3). Intermediate precision was below 2 % (n=3). The LOD and LOQ were 20 and 60 ng/zone for (1), 180 and 540 ng/zone for (2) and 140 and 430 ng/zone for (3), respectively. Average recovery was 100.1 % for (1) and (2) and 101.1 % for (3). 

J. Liq. Chromatogr. Relat. Technol. 44, 87-94 (2021). HPTLC fingerprinting of Selinum
tenuifolium on silica gel with toluene - ethyl acetate - formic acid 13:11:2. Detection under UV light at 254 nm and 366 nm. The hRF values for gallic acid and ferulic acid were 36 and 58, respectively. 

J. Liq. Chromatogr. Relat. Technol. 44, 33-51 (2021). Review of analytical techniques for the determination of haloperidol, including TLC and HPTLC. Methods for the quantification of haloperidol in plasma samples and dosage forms using reverse phase TLC and silica gel HPTLC plates were discussed. In addition, methods for the study of lipophilicity of haloperidol were described. 

J. Planar Chromatogr. 34, 157-163 (2021). HPTLC of berberine in the stem of Tinospora cordifolia on silica gel with n-hexane - ethyl acetate - methanol - formic acid 8:8:4:1. Quantitative determination by absorbance measurement at 360 nm. The hRF value for berberine was 48. Linearity was between 30 and 100 ng/zone. Intermediate precision was below 2 % (n=6). The LOD and LOQ were 10 and 30 ng/zone. Recovery was between 100.7 and 104.0 %. 

J. Planar Chromatogr. 34, 165-172 (2021). HPTLC of ursolic acid (1) and oleanolic acid (2) in the flowers of Punica granatum on silica gel with cyclohexane - ethyl acetate - methanol 82:18:5. Detection by dipping into 1 % sulfuric acid - ethanol solution, followed by heating at 105 ºC for 3 min. Quantitative determination by absorbance measurement at 530 nm. The hRF values for (1) and (2) were 43 and 62, respectively. Linearity was between 250 and 1503 ng/zone for (1) and 260 and 3633 ng/zone for (2). Intermediate precision was below 5 % (n=6). The LOD and LOQ were 10 and 33 ng for (1) and 20 and 67 ng for (2), respectively. Average recovery was 101.1 % for (1) and 100.1 % for (2).