β Scribed by Jacob Yashphe
No coin nor oath required. For personal study only.
Several methods for the quantitative estimation of the optically active isomers of tartaric acid are known (l-3). The smallest amounts of material which can be detected with these methods range from 1 to 3 ,umoles. For the determination of m-tartaric acid, the only method described in the literature cannot detect amounts less than about 400 pmoles (4). The method described in the present paper allows estimation of any of the three isomers of tartaric acid in amounts of 0.05 ,umole or more. The method is based on the formation of a tartrate-iron (Fe*) complex, which on addition of dinitrophenylhydraeine and alkali forms a purple colored compound. METHODS Materials and Apparatus Acetate buffer-O.1 M, pH 5.4 (B.D.H. Analar). Fe (NH,) 2 (SO,) 2 reagent-a solution of 0.015 M Fe (NH,) 2 (SO,),*6H,O (B.D.H. Analar) in 0.2N HCI (Baker Analyzed). NaH,P04 solution-0.01 M (Mallinckrodt A.R.). 2,4-Dinitrophenylhydrazine reagent-a solution of 0.05% DNPH (Eastman-Kodak) in 1 N HCl. NaOH solution-6 N (Baker USP). m-Tartaric acid (Calbiochem, C Grade). I-Tartaric acid (Calbiochem, A Grade). d-Tartaric acid (B.D.H. Analar). Klett-Summerson photoelectric calorimeter-Model 800-3, filter 54.
π SIMILAR VOLUMES
## Abstract A method is described for the estimation of alginic acid in seaseed samples, using the color reaction with carbazole and sulphuric acid, which can be applied on a micro scale, and is more rapid than the technique previously adopted.
Quantitative analysis o f DNA content represents a critical step when only very small amounts of nucleic acids are available. The DNA content of a small RNA-free sample can be measured in a simple and precise way using a two-dimensional approach. DNA samples are spotted on the surface o f an agarose
A new, rapid, simple, and sensitive calorimetric method for the estimation of resorcinol in microgram amounts is described. Rothera's test (1) has been routinely used to identify the presence of active -CH,-CO-CH,-groups in various biological samples. Thus, the formation of 3-oxoadipic acid from pr
The acid dye method for the estimation of certain alkaloids and other base compounds has been extended to atropine and other tropine alkaloids. This procedure is based on the observation that certain acidic dyes combine with many alkaloids to form saltlike compounds which are characterized by their