Diphenylamine derivatizing

In the derivatization of sugars with aniline-diphenylamine reagent for example, this leads to unsatisfactory irregular coloration. The standard deviation for the method deteriorates from 2 to 3% to 5 to 8%. For this reason color reactions should be avoided for direct quantitation if it is possible to scan in the UV range without derivatization. 

Derivatization reagent Thymol-sulfuric add Diphenylamine-aniline-phosphoric acid... 

Saad, B., N.H. Hanif, M.I. Saleh, N.H. Hasim, A. Abu, and N. Ali. 2004. Determination of o-phenylphenol, diphenyl and diphenylamine in apples and oranges using HPLC with fluorescence detection. Food Chem. 84(2) 313-317. Schmidt, T.C., M. Less, R. Haas, E. von Low, K. Steinbach, and G. Stork. 1998. Gas chromatographic determination of aromatic amines in water solid-phase extraction and derivatization with iodine. 7. Chromatogr. A 810 161-72. Thysen, B., S. K. Varma, and E. Bloch. 1985a. Reproductive toxicity of 2,4-toluenediamine in the rat. 1. Effect on male fertility. 7. Toxicol. Environ. Health 16 6) 753-61. 

Nucleic acids can also be quantified by derivat-ization. Thus, RNA is subjected to a multistep procedure in which the nucleic acids are decomposed to pentoses, which are subsequently converted into furfural by heating in an acidic medium. The furfural in turn reacts with orcinol to form a bluish-green condensation product with /lmax = 660nm. The de-oxyribose of DNA is quantified with diphenylamine in an acid medium. The linear determination range is from 10 to 100 tgml and the procedure is free from the interference of RNA. 

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