J. Planar Chromatogr. 4, 194-198 (1991). Study of the retention behavior of different penicillin and cephalosporin derivatives on silica impregnated with tricaprylmethylammonium chloride (TCMA) by OPLC with eluents containing water and methanol. The basis of retention is hydrophobic interaction, controlled by the surface concentration of TCMA; main advantage: retention is independent of the pH of the eluent.

CBS 98, 5-7 (2007). HPTLC of gatifloxacin on silica gel in a saturated twin-trough chamber with n-propanol - methanol - ammonia 25% 50:10:9 over 80 mm. Quantitative determination by absorbance measurement at 292 nm. The hRf value of gatifloxacin was 60 and selectivity regardnig matrix was given. Linearity was between 400 and 1200 ng/band. The intraday and interday precision both were below 0.03 %. The limit of detection and quantification was 2.7 and 8.3 ng/zone, respectively. Recovery was between 99.2 and 101.9 %. The HPTLC method was suited to study gatifloxacin stability under different stress conditions according to ICH guidelines (acid, base, heat, oxidation, photostability).

Chinese J. Pharm. Anal. 26 (2), 221-224 (2006). HPTLC of gentamycin and related compounds on silica gel with chloroform – methanol – 25 % ammonia 5:7:6. The main compound is well separated from the impurities. Quantification by densitometry at 485 nm. Linearity was between 4.0 – 40 ng/spot (r2 = 0.99) and the limit of detection was at the low ng level.

J. Planar Chromatogr. 26, 67-72 (2013). HPTLC of bacitracin derivative on silica gel with n-butanol - 2-butanone - 25 % ammonia - water 10:5:2:2. Quantitative determination by absorbance measurement at 460 nm. Linearity was in the range of 0.09-0.85 ng for bacitracine. LOD and LOQ were 9 ng/zone and 26 ng/zone, respectively. Intermediate precision was below 2.47 %. Comparable results with those obtained by spectrophotometric method.

J. Planar Chromatogr. 28, 67-73 (2015). HPTLC of (1) rifampicin, (2) isoniazid and (3) piperine on silica gel with toluene – methanol – chloroform 7:3:3. Quantitative determination by absorbance measurement at 300 nm. The hRF values of (1) to (3) were 51, 24 and 81, respectively. Linearities were between 100 and 700 ng/zone for (1) and (2) and between 20 and 90 ng/zone for (3). The intermediate intra-day and inter-day precisions for (1) to (3) were below 2 % (n=6). The LOD and LOQ were 12 and 33 ng/zone for (1), 20 and 53 ng/zone for (2) and 5 and 10 ng/zone for (3). Recoveries for (1) to (3) were in the range of 99-101 %.

J. Liq. Chromatogr. Relat. Technol. 39, 277-280 (2016). HPTLC of azithromycin (1), imipramine HCl (2), and sulfadoxine + pyrimethamine (3/4) on silica gel with methanol – ethyl acetate – concentrated ammonia 40:10:1 for (1), methanol – ammonia 96:1 for (2) and ethyl acetate – methanol 5:1 for (3/4). Quantitative determination by absorbance measurement at 254 nm. The hRF values were 54 for (1), 40 for (2), 67 for (3) and 45 for (4). Precisions for recovery were within 5 % and RSDs for triplicate assays and validation analyses at 50, 100, and 150 % spike levels were within 3 %._x000D_

J. Planar Chromatogr. 31, 163-168 (2018). HPTLC bioautography of the essential oil in the bark of Ocotea quixos on silica gel with toluene – ethyl acetate – petroleum ether 97:7:20. After separation, the Mueller‒Hinton culture medium was deposited on the Petri dish which contained the chromatographic plate. The medium contained the selected microorganisms: 500 μL Bacillus subtilis ATCC 6633 ATCC and 500 μL P. aeruginosa ATCC 9027. The plate was incubated at 37 °C for 48 h. The molecule with activity proved to be cinnamyl acetate at an hRF value of 53.

Acta Chimica 118, 25-29 (1985). TLC of the title compound, synthesized from D-1-galactose, on silica with dichloromethane - ethyl acetate 1:1, dichloromethane- acetone 9:1, petrol ether - ethyl acetate 7:3; staining with 50 % sulfuric acid.