J. Planar Chromatogr. 34, 411-418 (2021). HPTLC of sphingomyelin in erythrocyte membranes of patients on silica gel with chloroform - methanol - acetic acid - water 60:50:1:4. Detection by exposure to iodine vapor for 30 min. Quantitative determination by densitometric measurement of the intensity of individual zones and the red, green and blue values of the component colors. The hRF value for sphingomyelin was 86. Linearity was between 0.25 and 10 μg/zone. LOD and LOQ were 140 and 410 ng/zone, respectively. Intermediate precisions were below 2 % (n=3). Recovery was between 85 and 97 %.

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. 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. of Chromatogr. Sci. 58 (5), 411 - 417 (2020). Analysis of a binary mixture of silymarin (SR) and vitamin E (VE) acetate in their pure forms, pharmaceutical formulation and spiked human plasma, by HPTLC on silica gel with hexane - acetone - formic acid 140:60:3, detection at UV 215 nm, and quantification by densitometry. The linearity was 0.2 - 2.5 and 0.2 - 4.5 μg/band for SR and VE, respectively. Accuracy was 99.9 ± 1.2 % and 100.2 ± 1.6 % for SR and VE, respectively. The method was successfullly used for the determination of the studied drugs in their pharmaceutical formulation without any interference from excipients, and in spiked plasma samples. Statistical comparison of the results obtained by this HPTLC method showed no significant difference to the results obtained by the reported HPLC method.

J. Planar Chromatogr. 33, 419-425 (2020). Immunochromatography of cannabinoids (1) and opiates (2) in human urine using a test cassette device consisting of five parts, including a plastic backing, sample pad, conjugate pad, absorbent pad, and nitrocellulose (NC) membrane. Visual LOD was 50 ng/mL for (1) and 300 mg/mL for (2). Recovery was between 98 and 111 % for (1) and 101 and 110 % for (2).

J. Planar Chromatogr. 33, 271-279 (2020). Two-dimensional HPTLC of cholic, ursodeoxycholic, chenodeoxycholic, deoxycholic, and lithocholic bile acids on silica gel with 0.0001 M cetylpyridinium chloride at pH 9 with the addition of aliphatic alcohol modifiers 4 % 1-butanol (direction II) and 0.6 % 1-pentanol (direction II). Detection by drying the plate for 2-3 min in the oven at 120 ºC, followed by spraying with 8 % sulfuric acid in ethanol. Qualitative determination under UV light at 365 nm.

J. of Chromatogr. Sci. 57 (2), 130-138 (2019). Development of a method for the simultaneous determination of thalidomide (THD) and dexamethasone (DEX) in rat plasma using paracetamol as an internal standard by HPTLC on silica gel with methylene chloride - acetone - ethyl acetate 7:4:1. Detection by absorption measurement at 235 nm. Linearity was in the range of 0.02 - 100 µg/zone for THD and 0.02 - 3 µg/zone for DEX. LOD and LOQ were 7 and 20 ng/zone both for THD and DEX. Validation by testing all parameters using quality control samples as per FDA guidelines. Successful application of the method to study the pharmacokinetic parameters of both THD and DEX after their intra-peritoneal administration.

J. Planar Chromatogr. 32, 401-409 (2019). HPTLC of losartan potassium in plasma on silica gel with toluene - ethyl acetate - acetone - formic acid 8:8:2:1. Quantitative determination by absorbance measurement at 240 nm. The hRF value for losartan was 57. Linearity was between 50 and 1200 ng/mL. Intermediate precision was below 3 % (n=6). Recovery rate was between 95 and 99 %.