J. Chromatogr. 538, 165-175 (1991). TLC on silica with ethyl acetate – acetic acid 9:1 and chloroform – methanol – acetic acid 45:4:1. Detection under UV 376 nm. Characterization also by 1HNMR, plasma desorption MS, HPLC, UV spectrophotometry and melting point.

J. Planar Chromatogr. 6, 337-340 (1993). HPTLC of sulfameter (4-amino-N-(5-methoxy-2-pyrimidynyl)benzenesulfonamide), sulfamethoxazole and sulfisoxazole on (prewashed) silica with chloroform - ethyl acetate 4:6, horizontal development. Quantification by densitometry at 270 nm (absorbance).

Eastern Pharmacist 37, 179-180 (1994). HPTLC of anti-anxiety drugs amitriptyline and clordiazepoxide in tablets on silica (prewashed with methanol) with ethyl acetate - methanol - diethylamine 190:10:1. Quantification by densitometry at 245 nm. Recovery 100.8 - 102%.

J. Planar Chromatogr. 8, 314 - 318 (1995). Analysis of chloramphenicol-monosuccinate and gentamycin as example of the use of quantitative TLC for quality control of freshly produced drugs and those stored long-term. - TLC of chloramphenicol-monosuccinate sodium on silica with n-butyl acetate - acetic acid 24:1; quantification by densitometry at 280 nm. TLC of gentamycin on silica with the lower layer of a mixture of chloroform - methanol - NH3 conc. (after shaking) 1:1:1. Detection after derivatization with fluorescamine; quantification by densitometry (fluorescence) at 366 nm. Convenient, fast, cost-effective, simple screening procedure.

by thin-layer chromatography.) (Chinese). J. Chinese Trad. Patent Med. (Zhongchengyao) 17 (4), 1-3 (1995). TLC on silica with the upper phase of benzene - ethyl formate 4:1. Detection by exposure to NH3 vapor. Discussion of the dosage form by comparison of the chromatograms.

J. Planar Chromatogr. 10, 303-304 (1997). HPTLC of diltiazem (3-(acetyloxy)-5-[2-(dimethylamino)ethyl]-2,3-dihydro-2-(4-methoxyphenyl)-1,5-benzothiazepin-4(5H)-one) and desacetyldiltiazem on silica with chloroform - cyclohexane - toluene - diethylamine 30:20:20:3. Detection under UV 254 nm. Quantification by densitometry at 240 nm (absorbance). RSD of 2.2 and 0.9% (for two samples containing 0.23 and 0.68% of DAD); recovery (450 ng of D) was 99.7%; repeatability was 1.7%. Also published in Proc. 9th Internat. Symp. Instr. Chromatogr., Interlaken, April 9.-11., 1-4 (1997).

HPTLC with ultraviolet absorption densitometry on preadsorbent layers. Acta Chromatographica No. 7, 124-128 (1997). HPTLC on silica with ethyl acetate - acetic acid 19:1 in a vapor-equilibrated, paper-lined chamber, and on RP-18 with methanol - 0.5 M sodium chloride solution 11:9. Detection and quantification under UV 254 nm. Detection limit 0.25 µg. Recoveries and standard deviation are typical for those obtained for routine use of the method in a pharmaceutical laboratory. The TLC method involves very low solvent usage on a per sample basis compared to HPLC, leading to savings in purchase and disposal costs, and the ability to analyze multiple samples on a single plate containing only three standard zones permits very high sample throughput. Use of both NP- and RP-TLC provides excellent confirmation of qualitative and quantitative results.

J. Planar Chromatogr. 11, 222-224 (1998). HPTLC of propantheline bromide, 9-hydroxypropantheline bromide, xanthone, xanthoic acid on RP-18, pre-washed with methanol, with methanol - 0.1 M acetate buffer (pH 3.5) containing 25 mM sodium pentanesulfonate 31:9, in a chamber presaturated for 10 min. Densitometry by absorbance at 268 nm. Accuracy (expressed as percentage error) of the method was in the range of 0 - 4.5% and precision (expressed as % RSD) was in the range of 2 - 6%. Sensitive, accurate, and stability-indicating HPTLC method.