J. Planar Chromatogr. 21, 299-304 (2008). HPTLC of 21 amino acids on silica gel impregnated with 5 % Ag ion with borate phosphate buffer pH 2.3. After drying at 50 °C detection by spraying with ninhydrin. With this system separation of alanine, phenylalanine and tryptophane could be achieved, as well as separation of alanine, tyrosine and tryptophan. Separation of these amino acids was neither achieved on conventional silical gel (without Ag impregnation) nor by addtion of buffered 5 % silver nitrate solution (pH 2.3) to the mobile phase.

J. Planar Chromatogr. 26, 31-36 (2013). TLC of a five-component mixture of the amino acids lysine (1), histidine (2), leucine (3), alanine (4) and glutamic acid (4) on silica gel with 1.0% aqueous urea solution pH 7.44. The hRf values of amino acids (1) to (5) were 38, 59, 78, 87 and 98, respectively. LOD for (1), (3) and (4) was 1.5 µg/zone, whereas for (2) and (5) it was 1.2 and 3.0 µg/zone, respectively.

J. Planar Chromatogr. 29, 145-147 (2016). HPTLC of amino acids in seed cotyledons and seed coats from two types of legumes: black-eyed beans (Vigna unguiculata) and red kidney beans (Phaseolus vulgaris) on silica gel with n-butanol – glacial acetic acid – water 12:3:5. Detection by spraying with ninhydrin reagent 0.2 g/100 mL in ethanol, followed by heating at 80-100 °C for 5 min. The hRF values of essential and nonessential amino acids were determined and ranged between 13 and 62.

Proc. Intern. Symposium on TLC with special Emphasis on OPLC, Szeged, 93, (1984). TLC and OPTLC of L-lysine, formaldehyde on silica with citrate buffer pH 6.1. Detection with ninhydrin and heating at 80 °C for 10 minutes. Densitometry.

Detection by observing under UV 254 nm. Elution with ethanol containing NH3. Measurement by fluorometry 330/510 nm. Comparison of the results with those obtained by automated amino acid analyzer.

J. Chromatogr. 365, 289-296 (1986). TLC of methylated lysine and arginine derivatives on various silicas with various aqueous salt solutions. Investigation of the influence of the origin of silica, impregnation and salt quality on chromatographic performance. The origin of the silica has a dominant influence on chromatographic performance, and the effect of impregnation and salt quality are of secondary importance.

Biochemie und Physiologie der Pflanzen 182, 67-72 (1987). TLC of tryptophane, tyrosine, norepinephrine, serotonine and 5-hydroxyindole-3-acetic acid on silica with butanol - acetic acid - water 4:1:5. Running time 2 h at 25°C. After drying, spraying with OPT (indoles) or with 1-nitrose-2-naphthol. After 12 h examination under UV.

Plant Science 55, 21-25 (1988). Two-dimensional TLC of methionine and lipids on silica with acetone - benzene - methanol - water 8:3:2:1 for the first development and chloroform - acetone - methanol - acetic acid - water 10:4:2:3:1 for the second. Autoradiography.