J. Planar Chromatogr. 34, 243-252 (2021). HPTLC of dapagliflozin (1) and metformin (2) on silica gel with methanol - ethyl acetate - ammonium acetate 60:40:1. Quantitative determination by absorbance measurement at 220 nm. The hRF values for (1) and (2) were 79 and 31, respectively. Linearity was between 20 and 100 ng/zone for (1) and 500 and 2500 ng/zone for (2), respectively. Intermediate precisions were below 2 % (n=5). The LOD and LOQ were 3 and 10 ng/zone for (1) and 11 and 34 ng/zone for (2), respectively. Recovery was between 100.0 % and 101.6 % for (1) and 99.7 % and 101.1 % for (2).

J. Planar Chromatogr. 34, 211-215 (2021). HPTLC of acebutolol enantiomers on silica gel with acetonitrile - methanol - water 11:5:2. Detection by exposure to iodine vapor. The stationary phase with the chiral selector was prepared by mixing 25 g silica gel with 50 mL of a 50 mM solution of colistin sulfate, followed by drying and activation overnight at 60 °C. The LOD for each enantiomer of acebutolol was 12-15 μg/zone. Recovery was between 87 and 91 %.

J. Food Sci. 85, 3183-3190 (2020). HPTLC of astragalosides standards (I-IV) in Pleurotus ostreatus on silica gel with trichloromethane - methanol - ethyl acetate - water 13:7:2:2. Detection by spraying with 10 % sulfuric acid in ethanol and visualization under IV light at 365 nm. The hRF values for (I) to (IV) were 71, 54, 34 and 31, respectively. Further analysis by mass spectrometry.

Sens. Actuators. B. Chem. 299, 126902 (2019). TLC-surface-enhanced Raman scattering (TLC-SERS) of melamine contaminated milk samples on silica gel with acetone - chloroform - ammonia 14:1:4. Then 2 μL gold nanoparticle were drop onto the analyte spot. Quantification using a Raman microscope equipped with a CCD detector to acquire the surface-enhanced Raman scattering spectra. Excitation wavelength was 785 nm. A parallel representation model of the triple-spectral data was constructed using a pure quaternion matrix. Quaternion principal component analysis (QPCA) was utilized for feature extraction and followed by feature crossing between the quaternion principal components to obtain final fusion of spectral feature vectors.

Ars. Pharm. 62, 348-357 (2021). HPTLC of gallic acid (1), quercetin (2) and coumarin (3) in the leaves of Sonneratia apetala on silica gel with toluene - ethyl acetate - formic acid 45:30:2. Quantitative determination by absorbance measurement at 280 nm. The hRF values of (1) to (3) were 20, 42 and 51, respectively.

Pharmacogn. Mag. 17, 233-239 (2021). HPTLC of esculin in the leaves of Launaea pinnatifida on silica gel with chloroform - methanol - formic acid 13:6:1. Quantitative determination by absorbance measurement at 343 nm. The hRF value of esculin was 70. Linearity was between 8 and 250 µg/mL. The LOD and LOQ were 8 and 25 µg/zone. Average recovery rate was 99.8 %.

Bioorg. Chem. 88, 102947 (2019). HPTLC of pentylcurcumene in the aerial part of Geophila repens on silica gel with benzene - methanol 3:1. Quantitative determination by absorbance measurement at 254 nm. The hRF value of pentylcurcumene was 50. Linearity was between 100 and 500 ng/zone. The intermediate precision was below 2 % (n=3). The LOD and LOQ were 16 and 49 ng/zone. Recovery was between 97.2 and 98.7 %.

Rapid Commun. Mass Spectrom. 34, 8631 (2020). A 3D-printed, fully automated, open-source add-on user interface was built for elution-head-based TLC/HPTLC-MS. The system allowed a very compact plate-positioning system combined with an image-based software solution providing a platform to control and synchronize all steps from positioning, elution, advanced cleaning to MS data acquisition.