Asian J. Chem. 18(4), 2669-2672 (2006). TLC of lamivudine and zidovudine on silica gel with toluene - methanol - n-hexane 14:3:2. Quantitative determination by absorbance measurement at 275 nm. Linearity for lamivudine and zidovudine was in the range of 0.8-2.0 and 1.5-4.0 µg/zone, respectively. The average recovery was 99.4 - 100.3 % for both drugs. The method can be applied for routine simultaneous estimation in combined dosage form.

J. Pharm. Biomed. Anal. 18, 271-274 (1998). HPTLC of cephalexin on silica gel (prewashed with the mobile phase) with ethyl acetate - acetic acid - water 7:2:1. Quantitative determination by absorbance measurement at 263 nm. The method was linear in the range of 200-1600 ng/spot, average recovery was 101 %. The analytical results obtained by HPTLC were comparable with the HPLC method of USP XXIII. The HPTLC method was suggested as alternative to the USP method considering the high throughput.

Correlation of lipophilicity with affinity for alpha-adrenoceptors. J. Planar Chromatogr. 22, 141-144 (2009). Determination of the relative lipophilicity of 14 1-substituted pyrrolidin-2-one by TLC on RP-18 with mixtures of acetonitrile and pH 7.0 Tris buffer with volume fractions of acetonitrile between 20 and 80 %, with chamber saturation for 2 h. Detection under UV light. Retention data obtained by this method were exponentially dependent on acetonitrile concentration and enabled estimation of the relative lipophilicity corresponding to pH 7.0 Tris buffer as mobile phase.

Anal. Chim. Acta 598 (2), 312-317 (2007). TLC of paroxetine hydrochloride on silica gel with butanol - acetic acid - water 16:4:1. The hRf value of paroxetine HCl was 48 and separation from the degradation products (produced by acid and alkali hydrolysis, oxidation and photodegradation) was good. Quantitative determination by absorbance measurement at 295 nm. The linearity was in the range of 300 - 1500 ng/spot and the correlation coefficient was 0.9903. The limit of detection and quantitation was 50 and 150 ng/zone, respectively.

Abstract No. 9192, IHCB (2009). HPTLC of betulinic acid in hydro alcoholic extracts of Nelumbo nucifera rhizome and seed, on silica gel with chloroform - methanol - formic acid 49:1:1. Detection by spraying with anisaldehyde reagent. Quantitative determination by absorbance measurement at 420 nm. The method was linear in the range of 2-10 ng/spot, recovery was 98.1-98.4 %.

Chinese J. Pharm. Anal. 26 (2), 221-224 (2006). HPTLC of gentamycin and related compounds on silica gel with chloroform – methanol – 25 % ammonia 5:7:6. The main compound is well separated from the impurities. Quantification by densitometry at 485 nm. Linearity was between 4.0 – 40 ng/spot (r2 = 0.99) and the limit of detection was at the low ng level.

in vitro culture. Pharmazie 64, 694-696 (2009). Preparative TLC and HPTLC of protocatechuic acid, vanillic acid, syringic acid, and p-coumaric acid and methanolic extracts on silica gel. Detection under UV light at 254 nm.

J. Pharm. Biomed. Anal. 47, 790-794 (2008). HPTLC of the steviolbioside, stevioside and rebaudioside A in Stevia rebaudiana leaves on silica gel with ethyl acetate - ethanol - water 20:5:3. Detection by spraying with acetic anyhdride - sulphuric acid - ethanol 1:1:10 reagent. Quantitative determination by absorbance measurement at 510 nm. Linearity was in the range of 160-960 ng/spot for steviolbioside, 1-6 µg/spot for stevioside and 0.5-3 µg/spot for rebaudioside A with good correlation coefficients (0.998-0.999). The method was used for the assay of steviol glycosides in S. rebaudiana leaves collected from ten different locations.