59th Indian Pharmaceutical Congress C-100, 248, (2007). An HPTLC method has been developed for the estimation of flavonoids tannin and saponin in Caesalpinia bonduc. The dried powdered leaves of the plant were extracted with methanol and used for evaluation. HPTLC on silica gel with ethyl acetate - formic acid - glacial acetic acid - water 20:2:2:5 for flavonoids, chloroform - glacial acetic acid - methanol - water 16:8:3:2 for saponin, and ethyl acetate - toluene - formic acid 6:6:1 for tannin. Detection by spraying with 5 % methanolic sulphuric acid for saponin, 5 % alcoholic aluminium chloride solution for flavonoids, and 5 % ferric chloride solution for tannin. Densitometric evaluation at 254 nm and 366 nm.

59th Indian Pharmaceutical Congress C-220, 277, (2007). HPTLC of gallic acid in fruits of Emblica officinalis, on silica gel with touene - ethyl acetate - acetic acid - formic acid 4:9:4:3. Densitometry at 277 nm for quantitative evaluation. The method was linear in the range of 10 and 1000 ng/mL, with an average recovery of 101.4 %. The method was found suitable for routine quality check-up of Emblica officinalis.

J. Planar Chromatogr. 20, 283-285 (2007). TLC of benzalkonium bromide homologs (with C2, C4, C6 to C16, C18 C20) on silica gel in twin-trough chambers with isopropanol - water - acetic acid 1:1:4 or methanol - chloroform - acetic acid 50:10:1. Detection with iodine vapor or by derivatization with Dragendorff’s reagent.

Food Chem. 110, 538-546 (2008). TLC of wax esters of oilfish (Ruvettus pretiosus) and escolar (Lepidocybium flavobrunneum) on silica gel with xylene. Detection by spraying with 40 % sulfuric acid in ethanol - anisaldehyde 9:1, followed by heating at 100 °C for 2 min or until color is observed. The hRf value of wax esters was 60. The method was compared with DNA sequencing and GC-MS. The TLC method is inexpensive, provides a reliable result within 30 min, and is suitable for screening of numerous samples.

J. Planar Chromatogr. 21, 107-112 (2008). Optimization and comparison of the acidic visualization methods most often used for steroids. OPLC of ethinyl estradiol, ’dienolether’ (3-methoxyestra-2,5(10)-dien-17b-ol), norethisterone, norethisterone acetate, norethisterone enanthate, nandrolone, and nandrolone decanoate on HPTLC silica gel with cyclohexanone - ethyl acetate - chloroform 1:1:1. Detection with sulfuric acid at three different concentrations, phosphomolybdic acid, and phosphoric acid with different heating temperatures for different times. Evaluation under UV 366 nm (sulfuric acid, phosphoric acid) and in white light (phosphomolybdic acid). It was found that derivatization at higher temperatures for shorter periods usually results in greater sensitivity, although heating for longer periods at lower temperatures leads to a more stable and robust result. Evaluation by videodensitometry.

J. Chromatogr. Sci. 46 (4), 304-307 (2008). HPTLC rabeprazole and domperidone in pure powder and in capsule formulations on silica gel aluminium layers with ethyl acetate - methanol - benzene - acetonitrile 3:2:3:2. Quantification by absorbance measurement at 287 nm. Linearity was between 400 and 1200 ng/spot for rabeprazole and 600 and 1800 ng/spot for domperidone. Recovery was 99.8 % for rabeprazole and 99.4 % for domperidone. This method is simple, precise, and sensitive, and it is suitable for the simultaneous determination of rabeprazole and domperidone.

Microbiol. Res. 163, 307-313 (2008). HPTLC of norharmane from cyanobacterial culture medium extracts on silica gel with ethyl acetate - methanol - water 200:33:27 or ethyl acetate - formic acid - water 20:2:1. The hRf values of norharmane were 65 and 20, respectively. Evaluation under UV 254 nm without further derivatization. The screening of microalgal culture medium was performed by HPTLC and HPLC.

J. Chromatogr. A 1207 (1-2), 155-159 (2008). HPTLC of secoisolariciresinol diglucoside in flaxseed on RP18W with methanol - 0.1 % formic acid 2:3, using the alkaline hydrolysis in aqueous medium of undefatted samples. Quantitative determination by absorbance measurement at 282 nm. Validation of the method following the protocol proposed by the Société Francaise des Sciences et Techniques Pharmaceutiques lead to a dependable and high throughput procedure well suited for routine application. Linearity was between 321–1071 ng/zone and the RSD of repeatability and intermediate precision did not exceed 3.6 %.