Chinese J. Hospit. Pharm. 29 (4), 336-338 (2009). TLC of astragaloside in Tianjian capsules on silica gel with chloroform - methanol - water 13:6:2. Detection by spraying with 5 % sulfuric acid in ethanol followed by heating at 105 ºC until coloration. Quantification by densitometry at 515 nm. The linearity was between 0.98 and 4.90 µg/spot (r2 = 0.998), the %RSD was 2.4 % (n = 6) within plate and 2.3 % (n = 6) inter-plate, standard addition recovery was 99.2 % with RSD = 1.7 % (n = 6).

J. Planar Chromatogr. 23, 18-22 (2010). TLC of amphotericin B on silica gel with chloroform - methanol - borate buffer (pH 8.3) 4:5:1 in a chamber pre-saturated for 20 min. Detection under UV 366 nm. The hRf of the main component was 46, and of the minor component 31. Quantitative determination by absorbance measurement at 385 nm. Direct bioautography with Candida albicans proved to be the most sensitive method, with a detection limit of 0.8 ng per spot. For densitometric evaluation of plates at 385 nm ten times more substance is required.

J. Planar Chromatogr. 23, 134-136 (2010). TLC of sertraline on silica gel (prewashed with methanol) with chloroform - ethyl acetate - triethylamine 25:15:1 in a twin-trough chamber previously saturated for 10 min at room temperature. Quantitative determination by absorbance measurement at 279 nm. The hRf for sertraline was 40. Intra-day precision and inter-day precision was 99.84 % RSD and 99.92 % RSD, respectively. A good linear relationship between response (peak area) and amount was obtained over the range 2.7-7.9 µg/band.

J. Planar Chromatogr. 23, 148-155 (2010). HPTLC of rimonabant and degradation products on silica gel in a horizontal chamber with methanol - water 7:3. A compact band was obtained at hRf 71. Quantitative determination by absorbance measurement at 250 nm. Linear regression analysis of calibration data revealed good linear relationship with r = 0.9985 in the linear working range of 100-800 ng/band.

Encyclopedia of Chromatography Third Edition 1, 1640-1647 (2009). This review describes densitometry as the most widely used quantitative TLC method. The principles and theory of densitometry, as well as the instrumental design and data handling are also described. It also mentions in detail the applications and practical aspects of densitometry and finally describes the advantages of TLC/densitometry compared to HPLC.

Scholars Research Library 2(2), 328-332 (2010). A validated densitometric method has been development for simultaneous estimation of drotaverine and aceclofenac in combined dosage form. TLC on silica gel with methanol - ethyl acetate - glacial acetic acid 100:90:1. The hRf value of drotaverine was 18 and of aceclofenac 51. Densitometric evaluation at 300 nm. The method was linear in the range of 80-360 ng/band for drotaverine and 100-700 ng/band for aceclofenac. The average recovery was 99.8-100.2 %.

Eurasian J. Anal. Chem 5(1), 95-103 (2010). An HPTLC method is reported for quantification of glycyrrhetinic acid and apigenin in Glycyrrhiza glabra. Methanolic and acidic-methanolic extracts are subjected to chromatographic separation on silica gel with ethyl acetate - ethanol - water - 25 % ammonia 63:20:4:1. The method was linear in the range of 160-960 ng/band for glycyrrhetinic acid and 32-96 ng/band for apigenin. Glycyrrhiza glabra was found to contain 0.65 % of glycyrrhetinic acid and 0.0004 % of apigenin.

Analytical Chemistry - An Indian Journal 9(2) (2010) (without page number). An HPTLC method has been reported for estimation of beta-sitosterol in whole plant powder of Tridax procumbens. HPTLC on silica gel with toluene - ethyl acetate - glacial acetic acid 40:10:1. Methanolic extracts of the plant material were used. For detection the plate was sprayed with anisaldehyde - sulfuric acid reagent. Densitometric quantification at 550 nm. The method was linear in the range of 10.0-70.0 µg/band. The plant material was found to contain 0.04 % of beta-sitosterol. The proposed method was suitable for routine quality control of plant as well as quantification of beta-sitosterol .