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PAPER CHROMATOGRAPHY OF DNP-AMINO ACIDS

R_f VALUES IN VARIOUS SOLVENTS

	SOLVENT SYSTEM
DNP-derivative	1*	2	3	4*
DNP-alanine	0.45	0.44	0.58	0.53
α-DNP-arginine	0.48	0.74	0.57
DNP-aspartic acid	0.08	0.05	0.05	0.93
di-DNP-cystine	0.32	0.20	0.41	0.17
DNP-glutamic acid	0.09	0.05	0.06	0.85
DNP-glycine	0.35	0.33	0.45	0.42
di-DNP-histidine	0.43	0.32	0.47
DNP-isoleucine	0.64	0.68	0.80	0.51
DNP-leucine	0.64	0.68	0.80	0.51
di-DNP-lysine	0.72	0.75	0.78	0.08
ε-DNP-lysine	0.40	0.65	0.40
DNP-methionine	0.59	0.57	0.71	0.48
DNP-phenylalanine	0.66	0.68	0.80	0.33
DNP-proline	0.43	0.50		0.68
DNP-serine	0.30	0.23	0.45	0.68
DNP-threonine	0.36	0.31	0.53	0.75
DNP-tryptophan	0.62	0.63	0.75	0.15
di-DNP-tyrosine	0.74	0.70	0.83	0.04
DNP-valine	0.56	0.60	0.70	0.58
DNP-cysteic acid	0.02
2,4-dinitrophenol	0.44	0.25	0.62	0.42
2,4-dinitroalanine	1.00	1.00	1.00	0.08

SOLVENT SYSTEMS: (first three are odiforous; those in red stink!)

1. Toluene-pyridine-glycol monochlorohydrine-0.8N NH₄OH (5:1:3:3). (a)
2. Phenol-isoamylol-water (1:1:1). (a)
3. Pyridine-isoamylol-1.6N NH₄OH. (a)
4. 1.5M Phosphate buffer, pH 6. (b)

(a) Lederer & Lederer; Chromatography 2nd ed.; Elsevier (1957) p. 332.
(b) Levi; Nature 174 (1954), 126.