3. Test fungus: Candida albicans. J. Planar Chromatogr. 20, 385-389 (2007). Optimum conditions have been established for culture of the fungus Candida albicans for microbial detection of zones in direct bioautographic TLC. On the basis of the results with Candida albicans it can be differentiated between microbiostatic (bacteriostatic or fungistatic) and microbiocidal (bactericidal or fungicidal) effects on TLC plates. Aqueous solutions of amphotericin B and fluconazole were spotted on TLC plates coated with silica gel. After drying the plates were immersed in microbial suspensions with different optical densities. The viability and metabolic activity were evaluated by use of a bioluminescence ATP assay modified by Köszegi.

Bio. Chromatogr. 21(10), 1064-1068 (2008). Indirect chiral TLC separation of penicillamine (3,3-dimethylcysteine) enantiomers after derivatization with Marfey's reagent (FDNP-Ala-NH2) and two of its structural variants, FDNP-Phe-NH2 and FDNP-Val-NH2 on silica gel and RP-18 with phenol - water 3:1 and solvent combinations of acetonitrile and triethylamine phosphate buffer. The methods were applied for determination of the enantiomeric impurity of l-penicillamine, d-penicillamine, and pharmaceutical formulations of d-penicillamine.

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.

J. Chromatogr. 354, 317-324 (1986). TLC of aromatic heptaene antibiotics on silica with lower phase of mixture of chloroform - methanol - dioxane - acetic acid - 0.1 M ammonium pentaborate 33:38:9:1:19. Detection by spraying with anisaldehyde - sulfuric acid 1:1 and heating at 110 °C for 5 min. Comparison with HPLC method.