Proc. 6th Int. Symp. Instrum. Planar Chromatogr., (Interlaken 1991), Inst. Chromatogr., Bad Dürkheim, FRG, 291-299 (1991). The following HPTLC applications for pharmaceutica quality control are presented: 1) mono- and di(poyoxyethylene methylether)phosphates on silica with butanol - ethanol - 25% NH3 60:15:35, densitometry at 520 nm after dipping in a solution of Dragendorff’s reagent A, CV = 2% - 4%; 2) zardaverine on silica with TLC on silica with - ethyl acetate - methanol 4:4:2 , quantification by fluorescence; 3) escine on silica with propanol - ethyl acetate - water 4:3:3, detection by scanning at 540 nm after use of methanolic iron(III)chloride reagent, CV = 1.6 - 1.7 %; 4) neomycin (adaption of 1); 5) bacitracin (eleven components) on RP-8 silica with methanol - aq. sodium sulfate solution 0.1M 7:3, densitometry by fluorescence after derivatization with fluorescamine.

TLC in pharmacy: erythromycin. Deutsche Apotheker Zeitung 131, 2710-2711 (1991). TLC of erythromycin on silica with methanol – ethyl acetate 9:1. Visualization by spraying with ammonium-8-anilinonaphthaline-1-sulfonate, heating at 80 °C for some min and under UV 365 nm or by spraying with K2Cr2O7 – sulfuric acid reagent, heating at 90 °C for some min; observation under day light.

J. Planar Chromatogr. 7, 297-300 (1994). TLC for rapid and simple control of the purity of tetracyclines on silica with dichloromethane - methanol - water 60:35:5 for chlortetracycline and dichloromethane - methanol - water 59:35:6 for the other tetracyclines. Before use the plates were sprayed with a 10% solution of disodium EDTA, the pH of which had been adjusted with a 40% solution of sodium hydroxide to pH 8.0 for tetracycline, chlortetracycline, and demeclocycline and to pH 9.0 for oxytetracycline, doxycycline, and metacycline. Visualization and semi-quantitative assessment under UV 365 nm.

J. AOAC Int. 79, 1263-1268 (1996). TLC separation of erythromycin, tylosin and 11 other drugs (oxytetracycline, chlortetracycline-HCl, furazolidone, nitrofurazone, nitrofurantoin, sulfathiazole, sulfadiazine, sulfamerazine, amprolium, olaquindox, ronidazole) on silica with chloroform - methanol 10:1 with traces of NH3. Detection under UV 254 and 366 nm; also spraying with 10 % sulfuric acid in ethanol and heating at 120°C for 3 min.

Part III: Quantitation and evaluation of cephalosporins. J. Planar Chromatogr. 12, 114-119 (1999). Scanning densitometry for direct quantitation of cefoxitin, cefpirome, cefotaxime, cefoperazone, cefepime, ceftazidime, ceftizoxime, ceftriaxone, cefuroxime, cefotetan, cephalothin, and cefazolin on reversed-phase hydrocarbon-impregnated HPTLC silica gel plates without prior solvent elution. The samples remained as a single spot centered about the point of application, thereby facilitating direct quantitation by densitometry at different wavelengths.

J. Planar Chromatogr. 15, 187-191 (2002). TLC of flumequine and doxycycline on silica gel with and without a concentrating zone (after predeveloping with hexane and acetone) with 0.05 M citric acid - methanol - 2-propanol 1:3:1. Detection under UV 366 and 254 nm and by densitometry at 360 nm (for doxycycline) and at 325 nm (for flumequine). Bioautography by dipping the developed plates in a nutrient medium inoculated with Bacillus subtilis spore suspension and incubated overnight at 28°C. The plates were then sprayed with 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) solution and incubated for approximately 30 min.

J. AOAC Int. 88, 1555-1561 (2005). HPTLC of chloramphenicol on silica gel in a horizontal developing chamber (36 applications per plate) using n-hexane -ethyl acetate 7:13. Quantitative determination by absorbance measurement at 280 nm. Mean recovery was 95.8 %, and the coefficient of variation was 5.8 %. The detection limit was 3 ng, and the quantitation limit 10 ng.

Anal. Chem. 81, 3858-3866 (2009). HPTLC of microcystin LR and nodularin on silica gel with 1-propanol - ethyl acetate - water 3:5:2 with 5 % acetic acid. Detection and quantification by UV spectroscopy at 232 nm and direct identification of separated analytes on the HPTLC plate by IR-MALDI-o-TOF MS. The detection limit was 3-5 ng/zone. For detection of peptides, plates were cut and sprayed with a solution of p-anisaldehyde, followed by heating at 105 °C until purple-blue peptide spots appeared.