J. Chromatogr. B, 664, 311-316 (1995). An optimized gradient enabling the separation of all stratum corneum lipids by automated multiple development on HPTLC plates is presented. An initial isocratic step with toluene separates sebum lipids. This is followed by a 25-step development using a gradient with a polarity range of methanol - water to hexane. Post-chromatographic derivatization by spraying with 10% cupric sulfate pentahydrate in 8% o-phosphoric acid solution and heating for 10 min at 110 °C. Densitometric scanning by absorbance at 450 nm.

CBS 91, 2-4 (2003). HPTLC on silica gel with dichloromethane - methanol 93:7 over 50 mm after preconditioning for 10 min. Quantitative determination by absorbance measurement at 274 nm. Repeatability is better than 3.5 % and intermediate precision better than 5.1 %.

CBS 86, 13-15 (2001). HPTLC on silica gel (prewashed with methanol) with THF - toluene - formic acid - water 16:8:2:1 for flavonoids and toluene - ethyl acetate 9:2 for diterpenes. Detection of flavonoids by dipping in natural products reagent followed by dipping in PEG 6000 solution. Detection of diterpenes by dipping in anisaldehyde reagent. Evaluation with video technology.

CBS 83, 12-13 (1999) HPTLC of levamisol in pig tissue on silica gel with chloroform over a developing distance of 70 mm, then with chloroform - methanol - formic acid 400:50:1 over 50 mm. Quantitative determination by absorbance measurement at 220 nm. Limits of detection are 0.6 - 1.5 µg/kg.

J. Liq. Chrom. Rel. Technol. 27, 2087-2100 (2004). HPTLC of tetrandrine on silica gel with toluene - ethyl acetate - methanol - 28 % ammonia 100:100:50:3. Detection under UV light at 366 nm, and under white light after reaction with iodine (yellowish zones). If the plate is subsequently derivatized with anisaldehyde solution, the alkaloids show a strong blue fluorescence under UV light at 366 nm. Quantitative determination at 210 nm. The calibration curve is linear for 50 - 112.5 ng tetrandine per zone. Also HPTLC of aristolochic acids (AAs) on silica gel with the upper phase of toluene - ethyl acetate - water - formic acid 20:10:1:1 and derivatization with tin(II) chloride (to be prepared freshly: dissolve 1 g tin(II) chloride•2H2O in 1.5 mL 36 % hydrochloric acid diluted with 8 mL water), followed by heating at 100 °C for 1 min and evaluation under UV light at 366 nm. The method allows detection of 1 ppm of AA.

J. Planar Chromatogr. 17, 404-410 (2004). Highly reproducible retention was achieved when the adsorbent layer of the plate was pre-wetted and equilibrated with the mobile phase after adaptation of a horizonal DS chamber for electrochromatography in a closed (pressurized) system. The disadvantages of the open system, evaporation of the mobile phase from the plate and excessive flow of mobile phase to the surface of the adsorbent layer during development, were eliminated. Separation of a test dye mixture on pre-wetted RP-8 and RP-18 phases with acetonitrile - buffer and application of a potential of 2 kV to create the electric field. Detection by scanning in reflectance mode at 420 or 254 nm.

J. Planar Chromatogr. 17, 200-206 (2004). HPTLC of macrocyclic antibiotics (erythromycin, troleandomycin, tylosin, vancomycin, rifamycin B, and rifampicin) on LiChrospher silica gel. A wide range of mixtures of alcohols and ketones with hexamethyldisiloxane in proportions of 0 to 100 % and with dimethyl sulfoxide in proportions from 0 to 50 % were used as mobile phases. Separations were performed in chromatographic chambers after presaturation with mobile phase vapor. Detection by spraying with a 1:4 mixture of concentrated sulfuric acid and methanol followed by heating for approximately 10 min at 120 °C.

J. Planar Chromatogr. 17, 229-232 (2004). HPTLC of progesterone on silica gel in an automatic multiple development chamber (AMD) with toluene - 2-propanol 9:1 without chamber saturation and with 10 min drying time. Visual inspection under UV light at 254 nm. Quantitative determination in reflectance mode at 252 nm. Limits of quantitation and detection were 25 and 5 ng/zone.