Anal. Biochem. 282, 149-153 (2000). TLC of phosphorylated amino acids (phospholysine, phosphoserine, phosphothreonine, phosphoarginine, phosphotyrosine, phosphohistidine) on RP-18 with ethanol - NH3 conc. - water 65:10:16. Detection by spraying with 0.2% ninhydrin in ethanol and heating at 37°C for 30 min.

J. Liq. Chromatogr. Relat. Technol. 31, 763-771 (2008). TLC of 23 amino acids on silica gel with cetyltrimethylammonium bromide - n-butanol - n-octane - water microemulsion. Detection by spraying with ninhydrin reagent. Investigation of the effects of the hydrous content of microemulsion and structures of amino acids on the hRf values. Several amino acid mixtures were separated and determined using a microemulsion with 40 % hydrous content, which was compared with the traditional mobile phase ethanol - water - acetic acid.

J. Liq. Chromatogr. Relat. Technol. 35, 1497-1516 (2012). The authors reviewed stationary phases, solvent systems, and detection reagents developed for the analysis of amino acids. Polar and non-polar layers as well as impregnated layers mainly with metal ions and also with chiral agents were described for the separation and identification of amino acids. On the other hand, over fifty mobile phases were reviewed for the analysis of amino acids, with a recent tendency in the use of surfactants as less toxic reagents. Methodologies for the separation of amino acid enantiomers, such as the use of beta-cyclodextrin as chiral mobile phase as well as derivatization methods such as iodine azide reaction to enhance sensitivity in detection were also described. TLC has a privileged position due to its simplicity, convenience, and cost-effectiveness for separation of amino acids.

J. Planar Chromatogr. 29, 30-37 (2016). HPTLC and pressurized planar electrochromatography (PPEC) of 20 amino acids on silica gel with acetonitrile – buffer pH 3.2 (citric acid – disodium hydrogen phosphate 2.28:1.44) 1:1 for HPTLC and acetonitrile – buffer pH 3.2 4:1 for PPEC. PPEC separation was performed at a polarization voltage of 1.0 kV for 25 min. Detection by spraying with ninhydrin solution, followed by heating in a warm air stream.

J. Chromatogr. 299, 513-515 (1984). TLC and HPTLC of PTH derivatives of amino acids on silica containing a fluorescence indicator with ethanol - acetic acid 7:3. Detection by UV 366 nm. New and highly sensitive method for the detection of PTH-histidine (detection limit 60 pmol).

Fresenius Z. Anal. Chem. 322, 513-514 (1985). Proof of enantiomeric purity by TLC of D- and L- (3, 4-dihydroxyphenylalanine) on MN-chiral plates with methanol -water - acetonitrile 5:5:3. Spots are visualized using 0.1 % ninhydrin reagent.

Chromatographia 23, 141-142 (1987). TLC of enantiomeric mixtures of 9 DL-amino acids on silica, impregnated with (-)-brucine. with chloroform - butanol - acetic acid 4:3:1. Detection by spraying with ninhydrin and heating at 80 °C for 15-20 min.

(Hungarian). Kémiai Közlemények 65, 9-19 (1986). TLC of (D-thyroxine6)-GnRH, (D-thyronine6)-GnRH, (D-4-chloro-D-phenylalanine6)-GnRH, (D-thyroxine6)-GnRH-(1-9)-ethylamide, (D-thyronine6)-GnRH-(1-9)-ethyl-amide, (D-4-chloro-D-phenylalanine6)-GnRH-(1-9)-ethylamide on silica with 11 different solvent systems.