J.A.O.A.C. 69, 123-126 (1986). TLC of CPA and aflatoxins on silica. CPA on silica impregnated with 2 % ethanolic oxalic acid solution with benzene - acetic acid - methanol 90:5:7. Visualization by spraying with 1 % p-dimethylaminobenzaldehyde in 75 ml ethanol and 25 ml HCl. Aflatoxin with anhydrous ether - methanol - water 96:3:1. Patulin and griseofluvin with toluene - ethyl acetate - 90 % formic acid 5:4:1. Detection of grimeofluvin under UV 366 nm, of patulin by spraying with 0.5 % aqueous solution of 3-methyl-2- benzothiazolinone hydrazone and heating to 130 °C. Assessment by visual comparison with standards.

XIII. Systematic simultaneous analysis of residual tetracyclines in animal tissues using thin-layer and high-performance liquid chromatography. J. Chromatogr. 411, 313-323 (1987). TLC of residual tetracycline antibiotics on EDTA-treated silica with chloroform - methanol - 5% Na2EDTA 65:20:5, and on octyl-modified silica with methanol - methyl cyanide - 0.5M oxalic acid 1:1:4. Detection by spraying with 2N HCl and heating at 150 °C, also with 28 % NH3, 0.5 % aqueous Fast Blue BB salt, and then pyridine. Detection limit, 0.1 ppm.

II. Thin-layer chromatographic analysis of the stability of penicillins) (Chinese). J.Zhejiang Med.Univ. (Zhejian Yike Daxue Xuebao) 17, 118-120 (1988). TLC of penicillins on silica with micellar solutions containing 0.25% bromo-hexadecanylpyridine - acetic acid 10:1, 0.5% bromohexadecanylpyridine - acetic acid 20:3. Comparison of the results with those obtained with methanol - butanol - acetic acid 25:15:3. Investigation of the TLC conditions, developing time, temperature and pH, etc.

Acta Chimica, 128, 41-51 (1991). TLC separation of various 6-iodopenicillanic acid derivatives on silica with TLC toluene - ethyl acetate - formic acid - 7:3:1, acetone - acetic acid 85:15, ethyl acetate - acetic acid - water 3:1:1, benzene - ethyl acetate 1:1, chloroform - methanol 1:1 and chloroform - ether 9:1.

I. Qualitative aspects. J. Planar Chromatogr. 5, 92-98 (1992). TLC separation of tetracycline on silica impregnated by spraying with 10% disodium EDTA solution adjusted to pH 7.0 to 8.5 (depending upon the brand). Development with dichloromethane - methanol - water 59:35:6. Detection under UV 366 nm. Quantification by absorbance at 280 nm. Investigation of the influence of the pH of the EDTA spray solution on the quality of the separation by using the chromatographic response function (CRF), separation number and peak symmetry factor (S).

J. Chinese Agr. Chem. Soc. (Zhongguo Nongge Huaxue Huizhi) 32, 497-506 (1994). TLC on silica with ethyl acetate. Detection of monensin by bioautography using Bacillus subtillis. The recovery of monensin, 68.1 - 84.9% for beef, respectively. Detection limit 0.05 ppm.

Proc. 9th Internat. Symp. Instr. Chromatogr., Interlaken, April 9.-11., 373-381 (1997). TLC of bacitracin (which is a mixture of at least nine structurally related polypeptides with bacitracin A as major component of approx. 60%) on RP-8 silica at 6°C with methanol - 0.1 M sodium sulfate - triethylamine 70:29:1 adjusted to pH 2.0 with phosphoric acid. Postchromatographic derivatization by immersion the dried plate successively in solutions of triethylamine, fluram, and paraffin. Quantification by densitometry in fluorescence mode. Comparison data of microbial and HPTLC assay are mentioned. The outlined RP-HPTLC procedure allows a fast and reliable quantification of bacitracin in different pharmaceutical preparations and results in a reduction of more than 50% of the previously required analytical capacity.

Sz. Nyiredy, A. Kakuk (eds.): Planar Chromatography 2000, Lillafüred, Hungary, 24-26 June 2000, Res. Inst. for Med. Plants, p. 67-76. HPTLC of extracted feed sample on silica gel with different solvent systems: (1) acetonitrile, (2) acetonitrile - dichloromethane 49:1, (3) ethyl acetate - methanol - NH3 30:10:1. Bioautographic detection of antibiotics. (Description in this CBS p. 10.)